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Diffstat (limited to 'docs/html')
22 files changed, 1136 insertions, 38 deletions
diff --git a/docs/html/guide/guide_toc.cs b/docs/html/guide/guide_toc.cs index ba8dc5e..62d18ae 100644 --- a/docs/html/guide/guide_toc.cs +++ b/docs/html/guide/guide_toc.cs @@ -834,12 +834,6 @@ applications</span> <li><a href="<?cs var:toroot ?>guide/practices/ui_guidelines/widget_design.html"> <span class="en">App Widget Design</span> </a></li> - <li><a href="<?cs var:toroot ?>guide/practices/ui_guidelines/activity_task_design.html"> - <span class="en">Activity and Task Design</span> - </a></li> - <li><a href="<?cs var:toroot ?>guide/practices/ui_guidelines/menu_design.html"> - <span class="en">Menu Design</span> - </a></li> </ul> </li> </ul> diff --git a/docs/html/guide/practices/ui_guidelines/activity_task_design.jd b/docs/html/guide/practices/ui_guidelines/activity_task_design.jd index f8ca3f8..8e4528e 100644 --- a/docs/html/guide/practices/ui_guidelines/activity_task_design.jd +++ b/docs/html/guide/practices/ui_guidelines/activity_task_design.jd @@ -3,6 +3,43 @@ parent.title=UI Guidelines parent.link=index.html @jd:body + + + +<div id="deprecatedSticker"> + <a href="#" + onclick="$('#naMessage').show();$('#deprecatedSticker').hide();return false"> + <strong>This doc is deprecated</strong></a> +</div> + + +<div id="naMessage" style="display:block"> +<div><p><strong>This document has been deprecated.</strong></p> + <p>For information about designing an activity structure and navigation, read the design guidelines +for <a href="{@docRoot}design/patterns/app-structure.html">App Structure</a> and +<a href="{@docRoot}design/patterns/navigation.html">Navigation</a>, or the developer guide +about <a +href="{@docRoot}guide/topics/fundamentals/tasks-and-back-stack.html">Tasks and Back Stack</a>.</p> + + <input style="margin-top:1em;padding:5px" type="button" + value="That's nice, but I still want to read this document" +onclick="$('#naMessage').hide();$('#deprecatedSticker').show()" /> +</div> +</div> + + + + + + + + + + + + + + <div id="qv-wrapper"> <div id="qv"> diff --git a/docs/html/guide/practices/ui_guidelines/index.jd b/docs/html/guide/practices/ui_guidelines/index.jd index 3255275..24fb855 100644 --- a/docs/html/guide/practices/ui_guidelines/index.jd +++ b/docs/html/guide/practices/ui_guidelines/index.jd @@ -39,26 +39,6 @@ at a glance, on a user's Home screen. These design guidelines describe how to design widgets that fit with others on the Home screen. They include links to graphics files and templates that will make your designer's life easier.</dd> </dl> - <dl> - <dt><a href="{@docRoot}guide/practices/ui_guidelines/activity_task_design.html">Activity and Task Design Guidelines</a> </dt> - <dd>Activities are the basic, independent building blocks of applications. - As you design your application's UI and feature set, you are free to - re-use activities from other applications as if they were yours, - to enrich and extend your application. These guidelines - describe how activities work, illustrates them with examples, and - describes important underlying principles and mechanisms, such as - multitasking, activity reuse, intents, the activity stack, and - tasks. It covers this all from a high-level design perspective. -</dd> - <dt><a href="{@docRoot}guide/practices/ui_guidelines/menu_design.html">Menu Design Guidelines</a> </dt> - <dd>Android applications make use of Option menus and Context menus - that enable users to perform operations and navigate to other parts - of your application or to other applications. These guidelines describe - the difference between Options anontext menus, how to arrange - menu items, when to put commands on-screen, and other details about - menu design. -</dd> -</dl> diff --git a/docs/html/guide/practices/ui_guidelines/menu_design.jd b/docs/html/guide/practices/ui_guidelines/menu_design.jd index 7576b6c..b4e2ea7 100644 --- a/docs/html/guide/practices/ui_guidelines/menu_design.jd +++ b/docs/html/guide/practices/ui_guidelines/menu_design.jd @@ -2,7 +2,38 @@ page.title=Menu Design Guidelines parent.title=UI Guidelines parent.link=index.html @jd:body + + + + +<div id="deprecatedSticker"> + <a href="#" + onclick="$('#naMessage').show();$('#deprecatedSticker').hide();return false"> + <strong>This doc is deprecated</strong></a> +</div> + + +<div id="naMessage" style="display:block"> +<div><p><strong>This document has been deprecated.</strong></p> + <p>For design guidelines about adding user actions and other options, read the design guidelines +for <a href="{@docRoot}design/patterns/actionbar.html">Action Bar</a> or the developer guide about +<a href="{@docRoot}guide/topics/ui/menus.html">Menus</a>.</p> + + <input style="margin-top:1em;padding:5px" type="button" + value="That's nice, but I still want to read this document" +onclick="$('#naMessage').hide();$('#deprecatedSticker').show()" /> +</div> +</div> + + + + + + + + + <div id="qv-wrapper"> <div id="qv"> diff --git a/docs/html/guide/topics/ui/accessibility/apps.jd b/docs/html/guide/topics/ui/accessibility/apps.jd index ff34be6..dc91638 100644 --- a/docs/html/guide/topics/ui/accessibility/apps.jd +++ b/docs/html/guide/topics/ui/accessibility/apps.jd @@ -111,7 +111,7 @@ English language interface:</p> <p>By including the description, speech-based accessibility services can announce "Add note" when a user moves focus to this button or hovers over it.</p> -<p class="note">Note: For {@link android.widget.EditText} fields, provide an +<p class="note"><strong>Note:</strong> For {@link android.widget.EditText} fields, provide an <a href="{@docRoot}reference/android/widget/TextView.html#attr_android:hint">android:hint</a> attribute to help users understand what content is expected.</p> @@ -119,8 +119,10 @@ attribute to help users understand what content is expected.</p> <p>Focus navigation allows users with disabilities to step through user interface controls using a directional controller. Directional controllers can be physical, such as a clickable trackball, -directional pad (D-Pad) or arrow keys, tab key navigation with an attached keyboard or a software -application that provides an on-screen directional control.</p> +directional pad (D-pad) or arrow keys, tab key navigation with an attached keyboard or a software +application, such as the +<a href="https://play.google.com/store/apps/details?id=com.googlecode.eyesfree.inputmethod.latin"> +Eyes-Free Keyboard</a>, that provides an on-screen directional control.</p> <p>A directional controller is a primary means of navigation for many users. Verify that all user interface (UI) controls in your application are accessible @@ -566,5 +568,7 @@ option is not available.</p> <p>As part of your accessibility testing, you can test navigation of your application using focus, even if your test devices does not have a directional controller. The <a href="{@docRoot}guide/developing/tools/emulator.html">Android Emulator</a> provides a -simulated directional controller that you can easily use to test navigation. You can also use the -arrow keys and Enter key on your keyboard with the Emulator to simulate use of a D-pad.</p> +simulated directional controller that you can easily use to test navigation. You can also use a +software-based directional controller, such as the one provided by the +<a href="https://play.google.com/store/apps/details?id=com.googlecode.eyesfree.inputmethod.latin"> +Eyes-Free Keyboard</a> to simulate use of a D-pad.</p> diff --git a/docs/html/guide/topics/ui/declaring-layout.jd b/docs/html/guide/topics/ui/declaring-layout.jd index 4dc915f..8af4a1c 100644 --- a/docs/html/guide/topics/ui/declaring-layout.jd +++ b/docs/html/guide/topics/ui/declaring-layout.jd @@ -194,7 +194,7 @@ contains property types that define the size and position for each child view, a appropriate for the view group. As you can see in figure 1, the parent view group defines layout parameters for each child view (including the child view group).</p> -<img src="{@docRoot}images/layoutparams.png" alt="" height="300" align="center"/> +<img src="{@docRoot}images/layoutparams.png" alt="" /> <p class="img-caption"><strong>Figure 1.</strong> Visualization of a view hierarchy with layout parameters associated with each view.</p> diff --git a/docs/html/guide/topics/ui/index.jd b/docs/html/guide/topics/ui/index.jd index 83c8150..45c9ac9 100644 --- a/docs/html/guide/topics/ui/index.jd +++ b/docs/html/guide/topics/ui/index.jd @@ -51,7 +51,7 @@ as shown in the diagram below. This hierarchy tree can be as simple or complex a can build it up using Android's set of predefined widgets and layouts, or with custom Views that you create yourself.</p> -<img src="{@docRoot}images/viewgroup.png" alt="" width="312" height="211" align="center"/> +<img src="{@docRoot}images/viewgroup.png" alt="" /> <p> In order to attach the view hierarchy tree to the screen for rendering, your Activity must call the diff --git a/docs/html/images/layoutparams.png b/docs/html/images/layoutparams.png Binary files differindex 7473dcc..d99625e 100644 --- a/docs/html/images/layoutparams.png +++ b/docs/html/images/layoutparams.png diff --git a/docs/html/images/training/firstapp/adt-firstapp-setup.png b/docs/html/images/training/firstapp/adt-firstapp-setup.png Binary files differnew file mode 100644 index 0000000..c092562 --- /dev/null +++ b/docs/html/images/training/firstapp/adt-firstapp-setup.png diff --git a/docs/html/images/training/firstapp/edittext_gravity.png 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a/docs/html/sitemap.txt +++ b/docs/html/sitemap.txt @@ -160,8 +160,6 @@ http://developer.android.com/guide/practices/ui_guidelines/icon_design_tab.html http://developer.android.com/guide/practices/ui_guidelines/icon_design_dialog.html http://developer.android.com/guide/practices/ui_guidelines/icon_design_list.html http://developer.android.com/guide/practices/ui_guidelines/widget_design.html -http://developer.android.com/guide/practices/ui_guidelines/activity_task_design.html -http://developer.android.com/guide/practices/ui_guidelines/menu_design.html http://developer.android.com/guide/practices/design/performance.html http://developer.android.com/guide/practices/design/responsiveness.html http://developer.android.com/guide/practices/design/seamlessness.html diff --git a/docs/html/training/accessibility/index.jd b/docs/html/training/accessibility/index.jd index d5178a9..333f9f2 100644 --- a/docs/html/training/accessibility/index.jd +++ b/docs/html/training/accessibility/index.jd @@ -13,7 +13,6 @@ next.link=accessible-app.html <h2>Dependencies and prerequisites</h2> <ul> <li>Android 2.0 (API Level 5) or higher</li> -Playback</a></li> </ul> <h2>You should also read</h2> diff --git a/docs/html/training/basics/firstapp/building-ui.jd b/docs/html/training/basics/firstapp/building-ui.jd new file mode 100644 index 0000000..847163a --- /dev/null +++ b/docs/html/training/basics/firstapp/building-ui.jd @@ -0,0 +1,363 @@ +page.title=Building a Simple User Interface +parent.title=Building Your First App +parent.link=index.html + +trainingnavtop=true +previous.title=Running Your App +previous.link=running-app.html +next.title=Starting Another Activity +next.link=starting-activity.html + +@jd:body + + +<!-- This is the training bar --> +<div id="tb-wrapper"> +<div id="tb"> + +<h2>This lesson teaches you to</h2> + +<ol> + <li><a href="#LinearLayout">Use a Linear Layout</a></li> + <li><a href="#TextInput">Add a Text Input Box</a></li> + <li><a href="#Strings">Add String Resources</a></li> + <li><a href="#Button">Add a Button</a></li> + <li><a href="#Weight">Make the Input Box Fill in the Screen Width</a></li> +</ol> + + +<h2>You should also read</h2> +<ul> + <li><a href="{@docRoot}guide/topics/ui/declaring-layout.html">XML Layouts</a></li> +</ul> + + +</div> +</div> + + + +<p>The graphical user interface for an Android app is built using a hierarchy of {@link +android.view.View} and {@link android.view.ViewGroup} objects. {@link android.view.View} objects are +usually UI widgets such as a button or text field and {@link android.view.ViewGroup} objects are +invisible view containers that define how the child views are laid out, such as in a +grid or a vertical list.</p> + +<p>Android provides an XML vocabulary that corresponds to the subclasses of {@link +android.view.View} and {@link android.view.ViewGroup} so you can define your UI in XML with a +hierarchy of view elements.</p> + + +<div class="sidebox-wrapper"> +<div class="sidebox"> + <h2>Alternative Layouts</h2> + <p>Separating the UI layout into XML files is important for several reasons, +but it's especially important on Android because it allows you to define alternative layouts for +different screen sizes. For example, you can create two versions of a layout and tell +the system to use one on "small" screens and the other on "large" screens. For more information, +see the class about <a +href="{@docRoot}training/supporting-hardware/index.html">Supporting Various Hardware</a>.</p> +</div> +</div> + +<img src="{@docRoot}images/viewgroup.png" alt="" /> +<p class="img-caption"><strong>Figure 1.</strong> Illustration of how {@link +android.view.ViewGroup} objects form branches in the layout and contain {@link +android.view.View} objects.</p> + +<p>In this lesson, you'll create a layout in XML that includes a text input field and a +button. In the following lesson, you'll respond when the button is pressed by sending the +content of the text field to another activity.</p> + + + +<h2 id="LinearLayout">Use a Linear Layout</h2> + +<p>Open the <code>main.xml</code> file from the <code>res/layout/</code> +directory (every new Android project includes this file by default).</p> + +<p class="note"><strong>Note:</strong> In Eclipse, when you open a layout file, you’re first shown +the ADT Layout Editor. This is an editor that helps you build layouts using WYSIWYG tools. For this +lesson, you’re going to work directly with the XML, so click the <em>main.xml</em> tab at +the bottom of the screen to open the XML editor.</p> + +<p>By default, the <code>main.xml</code> file includes a layout with a {@link +android.widget.LinearLayout} root view group and a {@link android.widget.TextView} child view. +You’re going to re-use the {@link android.widget.LinearLayout} in this lesson, but change its +contents and layout orientation.</p> + +<p>First, delete the {@link android.widget.TextView} element and change the value +<a href="{@docRoot}reference/android/widget/LinearLayout.html#attr_android:orientation">{@code +android:orientation}</a> to be <code>"horizontal"</code>. The result looks like this:</p> + +<pre> +<?xml version="1.0" encoding="utf-8"?> +<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" + android:layout_width="fill_parent" + android:layout_height="fill_parent" + android:orientation="horizontal" > +</LinearLayout> +</pre> + +<p>{@link android.widget.LinearLayout} is a view group (a subclass of {@link +android.view.ViewGroup}) that lays out child views in either a vertical or horizontal orientation, +as specified by the <a +href="{@docRoot}reference/android/widget/LinearLayout.html#attr_android:orientation">{@code +android:orientation}</a> attribute. Each child of a {@link android.widget.LinearLayout} appears on +the screen in the order in which it appears in the XML.</p> + +<p>The other two attributes, <a +href="{@docRoot}reference/android/view/View.html#attr_android:layout_width">{@code +android:layout_width}</a> and <a +href="{@docRoot}reference/android/view/View.html#attr_android:layout_height">{@code +android:layout_height}</a>, are required for all views in order to specify their size.</p> + +<p>Because the {@link android.widget.LinearLayout} is the root view in the layout, it should fill +the entire screen area that's +available to the app by setting the width and height to +<code>"fill_parent"</code>.</p> + +<p class="note"><strong>Note:</strong> Beginning with Android 2.2 (API level 8), +<code>"fill_parent"</code> has been renamed <code>"match_parent"</code> to better reflect the +behavior. The reason is that if you set a view to <code>"fill_parent"</code> it does not expand to +fill the remaining space after sibling views are considered, but instead expands to +<em>match</em> the size of the parent view no matter what—it will overlap any sibling +views.</p> + +<p>For more information about layout properties, see the <a +href="{@docRoot}guide/topics/ui/declaring-layout.html">XML Layout</a> guide.</p> + + + +<h2 id="TextInput">Add a Text Input Box</h2> + +<p>To create a user-editable text box, add an {@link android.widget.EditText +<EditText>} element inside the {@link android.widget.LinearLayout <LinearLayout>}. The {@link +android.widget.EditText} class is a subclass of {@link android.view.View} that displays an editable +text box.</p> + +<p>Like every {@link android.view.View} object, you must define certain XML attributes to specify +the {@link android.widget.EditText} object's properties. Here’s how you should declare it +inside the {@link android.widget.LinearLayout <LinearLayout>} element:</p> + +<pre> + <EditText android:id="@+id/edit_message" + android:layout_width="wrap_content" + android:layout_height="wrap_content" + android:hint="@string/edit_message" /> +</pre> + + +<div class="sidebox-wrapper"> +<div class="sidebox"> + <h3>About resource objects</h3> + <p>A resource object is simply a unique integer name that's associated with an app resource, +such as a bitmap, layout file, or string.</p> + <p>Every resource has a +corresponding resource object defined in your project's {@code gen/R.java} file. You can use the +object names in the {@code R} class to refer to your resources, such as when you need to specify a +string value for the <a +href="{@docRoot}reference/android/widget/TextView.html#attr_android:hint">{@code android:hint}</a> +attribute. You can also create arbitrary resource IDs that you associate with a view using the <a +href="{@docRoot}reference/android/view/View.html#attr_android:id">{@code android:id}</a> attribute, +which allows you to reference that view from other code.</p> + <p>The SDK tools generate the {@code R.java} each time you compile your app. You should never +modify this file by hand.</p> +</div> +</div> + +<p>About these attributes:</p> + +<dl> +<dt><a href="{@docRoot}reference/android/view/View.html#attr_android:id">{@code android:id}</a></dt> +<dd>This provides a unique identifier for the view, which you can use to reference the object +from your app code, such as to read and manipulate the object (you'll see this in the next +lesson). + +<p>The at-symbol (<code>@</code>) is required when you want to refer to a resource object from +XML, followed by the resource type ({@code id} in this case), then the resource name ({@code +edit_message}). (Other resources can use the same name as long as they are not the same +resource type—for example, the string resource uses the same name.)</p> + +<p>The plus-symbol (<code>+</code>) is needed only when you're defining a resource ID for the +first time. It tells the SDK tools that the resource ID needs to be created. Thus, when the app is +compiled, the SDK tools use the ID value, <code>edit_message</code>, to create a new identifier in +your project's {@code gen/R.java} file that is now assiciated with the {@link +android.widget.EditText} element. Once the resource ID is created, other references to the ID do not +need the plus symbol. See the sidebox for more information about resource objects.</p></dd> + +<dt><a +href="{@docRoot}reference/android/view/View.html#attr_android:layout_width">{@code +android:layout_width}</a> and <a +href="{@docRoot}reference/android/view/View.html#attr_android:layout_height">{@code +android:layout_height}</a></dt> +<dd>Instead of using specific sizes for the width and height, the <code>"wrap_content"</code> value +specifies that the view should be only as big as needed to fit the contents of the view. If you +were to instead use <code>"fill_parent"</code>, then the {@link android.widget.EditText} +element would fill the screen, because it'd match the size of the parent {@link +android.widget.LinearLayout}. For more information, see the <a +href="{@docRoot}guide/topics/ui/declaring-layout.html">XML Layouts</a> guide.</dd> + +<dt><a +href="{@docRoot}reference/android/widget/TextView.html#attr_android:hint">{@code +android:hint}</a></dt> +<dd>This is a default string to display when the text box is empty. Instead of using a hard-coded +string as the value, the value given in this example refers to a string resource. When you add the +{@code +"@string/edit_message"} value, you’ll see a compiler error because there’s no matching string +resource by that name. You'll fix this in the next section by defining the string +resource.</dd> +</dl> + + + +<h2 id="Strings">Add String Resources</h2> + +<p>When you need to add text in the user interface, you should always specify each string of text in +a resource file. String resources allow you to maintain a single location for all string +values, which makes it easier to find and update text. Externalizing the strings also allows you to +localize your app to different languages by providing alternative definitions for each +string.</p> + +<p>By default, your Android project includes a string resource file at +<code>res/values/strings.xml</code>. Open this file, delete the existing <code>"hello"</code> +string, and add one for the +<code>"edit_message"</code> string used by the {@link android.widget.EditText <EditText>} +element.</p> + +<p>While you’re in this file, also add a string for the button you’ll soon add, called +<code>"button_send"</code>.</p> + +<p>The result for <code>strings.xml</code> looks like this:</p> + +<pre> +<?xml version="1.0" encoding="utf-8"?> +<resources> + <string name="app_name">My First App</string> + <string name="edit_message">Enter a message</string> + <string name="button_send">Send</string> +</resources> +</pre> + +<p>For more information about using string resources to localize your app for several languages, +see the <a +href="{@docRoot}training/basics/supporting-devices/index.html">Supporting Various Devices</a> +class.</p> + + + + +<h2 id="Button">Add a Button</h2> + +<p>Now add a {@link android.widget.Button <Button>} to the layout, immediately following the +{@link android.widget.EditText <EditText>} element:</p> + +<pre> + <Button + android:layout_width="wrap_content" + android:layout_height="wrap_content" + android:text="@string/button_send" /> +</pre> + +<p>The height and width are set to <code>"wrap_content"</code> so the button is only as big as +necessary to fit the button's text.</p> + + + +<h2 id="Weight">Make the Input Box Fill in the Screen Width</h2> + +<p>The layout is currently designed so that both the {@link android.widget.EditText} and {@link +android.widget.Button} widgets are only as big as necessary to fit their content, as shown in +figure 2.</p> + +<img src="{@docRoot}images/training/firstapp/edittext_wrap.png" /> +<p class="img-caption"><strong>Figure 2.</strong> The {@link android.widget.EditText} and {@link +android.widget.Button} widgets have their widths set to +<code>"wrap_content"</code>.</p> + +<p>This works fine for the button, but not as well for the text box, because the user might type +something longer and there's extra space left on the screen. So, it'd be nice to fill that width +using the text box. +{@link android.widget.LinearLayout} enables such a design with the <em>weight</em> property, which +you can specify using the <a +href="{@docRoot}reference/android/widget/LinearLayout.LayoutParams.html#weight">{@code +android:layout_weight}</a> attribute.</p> + +<p>The weight value allows you to specify the amount of remaining space each view should consume, +relative to the amount consumed by sibling views, just like the ingredients in a drink recipe: "2 +parts vodka, 1 part coffee liquer" means two-thirds of the drink is vodka. For example, if you give +one view a weight of 2 and another one a weight of 1, the sum is 3, so the first view gets 2/3 of +the remaining space and the second view gets the rest. If you give a third view a weight of 1, +then the first view now gets 1/2 the remaining space, while the remaining two each get 1/4.</p> + +<p>The default weight for all views is 0, so if you specify any weight value +greater than 0 to only one view, then that view fills whatever space remains after each view is +given the space it requires. So, to fill the remaining space with the {@link +android.widget.EditText} element, give it a weight of 1 and leave the button with no weight.</p> + +<pre> + <EditText + android:layout_weight="1" + ... /> +</pre> + +<p>In order to improve the layout efficiency when you specify the weight, you should change the +width of the {@link android.widget.EditText} to be +zero (0dp). Setting the width to zero improves layout performance because using +<code>"wrap_content"</code> as the width requires the system to calculate a width that is +ultimately irrelevant because the weight value requires another width calculation to fill the +remaining space.</p> +<pre> + <EditText + android:layout_weight="1" + android:layout_width="0dp" + ... /> +</pre> + +<p>Figure 3 +shows the result when you assign all weight to the {@link android.widget.EditText} element.</p> + +<img src="{@docRoot}images/training/firstapp/edittext_gravity.png" /> +<p class="img-caption"><strong>Figure 3.</strong> The {@link android.widget.EditText} widget is +given all the layout weight, so fills the remaining space in the {@link +android.widget.LinearLayout}.</p> + +<p>Here’s how your complete layout file should now look:</p> + +<pre> +<?xml version="1.0" encoding="utf-8"?> +<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" + android:layout_width="fill_parent" + android:layout_height="fill_parent" + android:orientation="horizontal"> + <EditText android:id="@+id/edit_message" + android:layout_weight="1" + android:layout_width="0dp" + android:layout_height="wrap_content" + android:hint="@string/edit_message" /> + <Button android:id="@+id/button_send" + android:layout_width="wrap_content" + android:layout_height="wrap_content" + android:text="@string/button_send" /> +</LinearLayout> +</pre> + +<p>This layout is applied by the default {@link android.app.Activity} class +that the SDK tools generated when you created the project, so you can now run the app to see the +results:</p> + +<ul> + <li>In Eclipse, click <strong>Run</strong> from the toolbar.</li> + <li>Or from a command line, change directories to the root of your Android project and +execute: +<pre> +ant debug +adb install bin/MyFirstApp-debug.apk +</pre></li> +</ul> + +<p>Continue to the next lesson to learn how you can respond to button presses, read content +from the text field, start another activity, and more.</p> + + + diff --git a/docs/html/training/basics/firstapp/creating-project.jd b/docs/html/training/basics/firstapp/creating-project.jd new file mode 100644 index 0000000..5a89f2e --- /dev/null +++ b/docs/html/training/basics/firstapp/creating-project.jd @@ -0,0 +1,142 @@ +page.title=Creating an Android Project +parent.title=Building Your First App +parent.link=index.html + +trainingnavtop=true +next.title=Running Your App +next.link=running-app.html + +@jd:body + + +<!-- This is the training bar --> +<div id="tb-wrapper"> +<div id="tb"> + +<h2>This lesson teaches you to</h2> + +<ol> + <li><a href="#Eclipse">Create a Project with Eclipse</a></li> + <li><a href="#CommandLine">Create a Project with Command Line Tools</a></li> +</ol> + +<h2>You should also read</h2> + +<ul> + <li><a href="{@docRoot}sdk/installing.html">Installing the +SDK</a></li> + <li><a href="{@docRoot}guide/developing/projects/index.html">Managing Projects</a></li> +</ul> + + +</div> +</div> + +<p>An Android project contains all the files that comprise the source code for your Android +app. The Android SDK tools make it easy to start a new Android project with a set of +default project directories and files.</p> + +<p>This lesson +shows how to create a new project either using Eclipse (with the ADT plugin) or using the +SDK tools from a command line.</p> + +<p class="note"><strong>Note:</strong> You should already have the Android SDK installed, and if +you're using Eclipse, you should have installed the <a +href="{@docRoot}sdk/eclipse-adt.html">ADT plugin</a> as well. If you have not installed +these, see <a href="{@docRoot}sdk/installing.html">Installing the Android SDK</a> and return here +when you've completed the installation.</p> + + +<h2 id="Eclipse">Create a Project with Eclipse</h2> + +<div class="figure" style="width:416px"> +<img src="{@docRoot}images/training/firstapp/adt-firstapp-setup.png" alt="" /> +<p class="img-caption"><strong>Figure 1.</strong> The new project wizard in Eclipse.</p> +</div> + +<ol> + <li>In Eclipse, select <strong>File > New > Project</strong>. +The resulting dialog should have a folder labeled <em>Android</em>. (If you don’t see the +<em>Android</em> folder, +then you have not installed the ADT plugin—see <a +href="{@docRoot}sdk/eclipse-adt.html#installing">Installing the ADT Plugin</a>).</li> + <li>Open the <em>Android</em> folder, select <em>Android Project</em> and click +<strong>Next</strong>.</li> + <li>Enter a project name (such as "MyFirstApp") and click <strong>Next</strong>.</li> + <li>Select a build target. This is the platform version against which you will compile your app. +<p>We recommend that you select the latest version possible. You can still build your app to +support older versions, but setting the build target to the latest version allows you to +easily optimize your app for a great user experience on the latest Android-powered devices.</p> +<p>If you don't see any built targets listed, you need to install some using the Android SDK +Manager tool. See <a href="{@docRoot}sdk/installing.html#AddingComponents">step 4 in the +installing guide</a>.</p> +<p>Click <strong>Next</strong>.</p></li> + <li>Specify other app details, such as the: + <ul> + <li><em>Application Name</em>: The app name that appears to the user. Enter "My First +App".</li> + <li><em>Package Name</em>: The package namespace for your app (following the same +rules as packages in the Java programming language). Your package name +must be unique across all packages installed on the Android system. For this reason, it's important +that you use a standard domain-style package name that’s appropriate to your company or +publisher entity. For +your first app, you can use something like "com.example.myapp." However, you cannot publish your +app using the "com.example" namespace.</li> + <li><em>Create Activity</em>: This is the class name for the primary user activity in your +app (an activity represents a single screen in your app). Enter "MyFirstActivity".</li> + <li><em>Minimum SDK</em>: Select <em>4 (Android 1.6)</em>. + <p>Because this version is lower than the build target selected for the app, a warning +appears, but that's alright. You simply need to be sure that you don't use any APIs that require an +<a href="{@docRoot}guide/appendix/api-levels.html">API level</a> greater than the minimum SDK +version without first using some code to verify the device's system version (you'll see this in some +other classes).</p> + </li> + </ul> + <p>Click <strong>Finish</strong>.</p> + </li> +</ol> + +<p>Your Android project is now set up with some default files and you’re ready to begin +building the app. Continue to the <a href="running-app.html">next lesson</a>.</p> + + + +<h2 id="CommandLine">Create a Project with Command Line Tools</h2> + +<p>If you're not using the Eclipse IDE with the ADT plugin, you can instead create your project +using the SDK tools in a command line:</p> + +<ol> + <li>Change directories into the Android SDK’s <code>tools/</code> path.</li> + <li>Execute: +<pre class="no-pretty-print">android list targets</pre> +<p>This prints a list of the available Android platforms that you’ve downloaded for your SDK. Find +the platform against which you want to compile your app. Make a note of the target id. We +recommend that you select the highest version possible. You can still build your app to +support older versions, but setting the build target to the latest version allows you to optimize +your app for the latest devices.</p> +<p>If you don't see any targets listed, you need to +install some using the Android SDK +Manager tool. See <a href="{@docRoot}sdk/installing.html#AddingComponents">step 4 in the +installing guide</a>.</p></li> + <li>Execute: +<pre class="no-pretty-print"> +android create project --target <target-id> --name MyFirstApp \ +--path <path-to-workspace>/MyFirstApp --activity MyFirstActivity \ +--package com.example.myapp +</pre> +<p>Replace <code><target-id></code> with an id from the list of targets (from the previous step) +and replace +<code><path-to-workspace></code> with the location in which you want to save your Android +projects.</p></li> +</ol> + +<p>Your Android project is now set up with several default configurations and you’re ready to begin +building the app. Continue to the <a href="running-app.html">next lesson</a>.</p> + +<p class="note"><strong>Tip:</strong> Add the <code>platform-tools/</code> as well as the +<code>tools/</code> directory to your <code>PATH</code> environment variable.</p> + + + + diff --git a/docs/html/training/basics/firstapp/index.jd b/docs/html/training/basics/firstapp/index.jd new file mode 100644 index 0000000..a95ed8e --- /dev/null +++ b/docs/html/training/basics/firstapp/index.jd @@ -0,0 +1,64 @@ +page.title=Building Your First App + +trainingnavtop=true +startpage=true +next.title=Creating an Android Project +next.link=creating-project.html + +@jd:body + +<div id="tb-wrapper"> +<div id="tb"> + +<h2>Dependencies and prerequisites</h2> + +<ul> + <li>Android 1.6 or higher</li> + <li><a href="http://developer.android.com/sdk/index.html">Android SDK</a></li> +</ul> + +</div> +</div> + +<p>Welcome to Android application development!</p> + +<p>This class teaches you how to build your first Android app. You’ll learn how to create an Android +project and run a debuggable version of the app. You'll also learn some fundamentals of Android app +design, including how to build a simple user interface and handle user input.</p> + +<p>Before you start this class, be sure that you have your development environment set up. You need +to:</p> +<ol> + <li>Download the Android SDK Starter Package.</li> + <li>Install the ADT plugin for Eclipse (if you’ll use the Eclipse IDE).</li> + <li>Download the latest SDK tools and platforms using the SDK Manager.</li> +</ol> + +<p>If you haven't already done this setup, read <a href="{@docRoot}sdk/installing.html">Installing +the SDK</a>. Once you've finished the setup, you're ready to begin this class.</p> + +<p>This class uses a tutorial format that incrementally builds a small Android app in order to teach +you some fundamental concepts about Android development, so it's important that you follow each +step.</p> + +<p><strong><a href="creating-project.html">Start the first lesson ›</a></strong></p> + + +<h2>Lessons</h2> + +<dl> + <dt><b><a href="creating-project.html">Creating an Android Project</a></b></dt> + <dd>Shows how to create a project for an Android app, which includes a set of default +app files.</dd> + + <dt><b><a href="running-app.html">Running Your Application</a></b></dt> + <dd>Shows how to run your app on an Android-powered device or the Android +emulator.</dd> + + <dt><b><a href="building-ui.html">Building a Simple User Interface</a></b></dt> + <dd>Shows how to create a new user interface using an XML file.</dd> + + <dt><b><a href="starting-activity.html">Starting Another Activity</a></b></dt> + <dd>Shows how to respond to a button press, start another activity, send it some +data, then receive the data in the subsequent activity.</dd> +</dl> diff --git a/docs/html/training/basics/firstapp/running-app.jd b/docs/html/training/basics/firstapp/running-app.jd new file mode 100644 index 0000000..2398fa0 --- /dev/null +++ b/docs/html/training/basics/firstapp/running-app.jd @@ -0,0 +1,178 @@ +page.title=Running Your App +parent.title=Building Your First App +parent.link=index.html + +trainingnavtop=true +previous.title=Creating a Project +previous.link=creating-project.html +next.title=Building a Simple User Interface +next.link=building-ui.html + +@jd:body + + +<!-- This is the training bar --> +<div id="tb-wrapper"> +<div id="tb"> + +<h2>This lesson teaches you to</h2> + +<ol> + <li><a href="#RealDevice">Run on a Real Device</a></li> + <li><a href="#Emulator">Run on the Emulator</a></li> +</ol> + +<h2>You should also read</h2> + +<ul> + <li><a href="{@docRoot}guide/developing/device.html">Using Hardware Devices</a></li> + <li><a href="{@docRoot}guide/developing/devices/index.html">Managing Virtual Devices</a></li> + <li><a href="{@docRoot}guide/developing/projects/index.html">Managing Projects</a></li> +</ul> + + +</div> +</div> + + +<p>If you followed the <a href="{@docRoot}creating-project.html">previous lesson</a> to create an +Android project, it includes a default set of "Hello World" source files that allow you to +run the app right away.</p> + +<p>How you run your app depends on two things: whether you have a real Android-powered device and +whether you’re using Eclipse. This lesson shows you how to install and run your app on a +real device and on the Android emulator, and in both cases with either Eclipse or the command line +tools.</p> + +<p>Before you run your app, you should be aware of a few directories and files in the Android +project:</p> + +<dl> + <dt><code>AndroidManifest.xml</code></dt> + <dd>This manifest file describes the fundamental characteristics of the app and defines each of +its components. You'll learn about various declarations in this file as you read more training +classes.</dd> + <dt><code>src/</code></dt> + <dd>Directory for your app's main source files. By default, it includes an {@link +android.app.Activity} class that runs when your app is launched using the app icon.</dd> + <dt><code>res/</code></dt> + <dd>Contains several sub-directories for app resources. Here are just a few: + <dl style="margin-top:1em"> + <dt><code>drawable-hdpi/</code></dt> + <dd>Directory for drawable objects (such as bitmaps) that are designed for high-density +(hdpi) screens. Other drawable directories contain assets designed for other screen densities.</dd> + <dt><code>layout/</code></dt> + <dd>Directory for files that define your app's user interface.</dd> + <dt><code>values/</code></dt> + <dd>Directory for other various XML files that contain a collection of resources, such as +string and color definitions.</dd> + </dl> + </dd> +</dl> + +<p>When you build and run the default Android project, the default {@link android.app.Activity} +class in the <code>src/</code> directory starts and loads a layout file from the +<code>layout/</code> directory, which includes a "Hello World" message. Not real exciting, but it's +important that you understand how to build and run your app before adding real functionality to +the app.</p> + + + +<h2 id="RealDevice">Run on a Real Device</h2> + +<p>Whether you’re using Eclipse or the command line, you need to:</p> + +<ol> + <li>Plug in your Android-powered device to your machine with a USB cable. +If you’re developing on Windows, you might need to install the appropriate USB driver for your +device. For help installing drivers, see the <a href=”{@docRoot}sdk/oem-usb.html”>OEM USB +Drivers</a> document.</li> + <li>Ensure that <strong>USB debugging</strong> is enabled in the device Settings (open Settings +and navitage to <strong>Applications > Development</strong> on most devices, or select +<strong>Developer options</strong> on Android 4.0 and higher).</li> +</ol> + +<p>To run the app from Eclipse, open one of your project's files and click +<strong>Run</strong> from the toolbar. Eclipse installs the app on your connected device and starts +it.</p> + + +<p>Or to run your app from a command line:</p> + +<ol> + <li>Change directories to the root of your Android project and execute: +<pre class="no-pretty-print">ant debug</pre></li> + <li>Make sure the Android SDK <code>platform-tools/</code> directory is included in your +<code>PATH</code> environment variable, then execute: +<pre class="no-pretty-print">adb install bin/MyFirstApp-debug.apk</pre></li> + <li>On your device, locate <em>MyFirstActivity</em> and open it.</li> +</ol> + +<p>To start adding stuff to the app, continue to the <a href="building-ui.html">next +lesson</a>.</p> + + + +<h2 id="Emulator">Run on the Emulator</h2> + +<p>Whether you’re using Eclipse or the command line, you need to first create an <a +href="{@docRoot}guide/developing/devices/index.html">Android Virtual +Device</a> (AVD). An AVD is a +device configuration for the Android emulator that allows you to model +different device configurations.</p> + +<div class="figure" style="width:457px"> + <img src="{@docRoot}images/screens_support/avds-config.png" alt="" /> + <p class="img-caption"><strong>Figure 1.</strong> The AVD Manager showing a few virtual +devices.</p> +</div> + +<p>To create an AVD:</p> +<ol> + <li>Launch the Android Virtual Device Manager: + <ol type="a"> + <li>In Eclipse, select <strong>Window > AVD Manager</strong>, or click the <em>AVD +Manager</em> icon in the Eclipse toolbar.</li> + <li>From the command line, change directories to <code><sdk>/tools/</code> and execute: +<pre class="no-pretty-print">./android avd</pre></li> + </ol> + </li> + <li>In the <em>Android Virtual Device Device Manager</em> panel, click <strong>New</strong>.</li> + <li>Fill in the details for the AVD. +Give it a name, a platform target, an SD card size, and a skin (HVGA is default).</li> + <li>Click <strong>Create AVD</strong>.</li> + <li>Select the new AVD from the <em>Android Virtual Device Manager</em> and click +<strong>Start</strong>.</li> + <li>After the emulator boots up, unlock the emulator screen.</li> +</ol> + +<p>To run the app from Eclipse, open one of your project's files and click +<strong>Run</strong> from the toolbar. Eclipse installs the app on your AVD and starts it.</p> + + +<p>Or to run your app from the command line:</p> + +<ol> + <li>Change directories to the root of your Android project and execute: +<pre class="no-pretty-print">ant debug</pre></li> + <li>Make sure the Android SDK <code>platform-tools/</code> directory is included in your +<code>PATH</code> environment +variable, then execute: +<pre class="no-pretty-print">adb install bin/MyFirstApp-debug.apk</pre></li> + <li>On the emulator, locate <em>MyFirstActivity</em> and open it.</li> +</ol> + + +<p>To start adding stuff to the app, continue to the <a href="building-ui.html">next +lesson</a>.</p> + + + + + + + + + + + diff --git a/docs/html/training/basics/firstapp/starting-activity.jd b/docs/html/training/basics/firstapp/starting-activity.jd new file mode 100644 index 0000000..16a6fd8 --- /dev/null +++ b/docs/html/training/basics/firstapp/starting-activity.jd @@ -0,0 +1,308 @@ +page.title=Starting Another Activity +parent.title=Building Your First App +parent.link=index.html + +trainingnavtop=true +previous.title=Building a Simpler User Interface +previous.link=building-ui.html + +@jd:body + + +<!-- This is the training bar --> +<div id="tb-wrapper"> +<div id="tb"> + +<h2>This lesson teaches you to</h2> + +<ol> + <li><a href="#RespondToButton">Respond to the Send Button</a></li> + <li><a href="#BuildIntent">Build an Intent</a></li> + <li><a href="#StartActivity">Start the Second Activity</a></li> + <li><a href="#CreateActivity">Create the Second Activity</a> + <ol> + <li><a href="#AddToManifest">Add it to the manifest</a></li> + </ol> + </li> + <li><a href="#ReceiveIntent">Receive the Intent</a></li> + <li><a href="#DisplayMessage">Display the Message</a></li> +</ol> + +<h2>You should also read</h2> + +<ul> + <li><a href="{@docRoot}sdk/installing.html">Installing the +SDK</a></li> +</ul> + + +</div> +</div> + + + +<p>After completing the <a href="building-ui.html">previous lesson</a>, you have an app that +shows an activity (a single screen) with a text box and a button. In this lesson, you’ll add some +code to <code>MyFirstActivity</code> that +starts a new activity when the user selects the Send button.</p> + + +<h2 id="RespondToButton">Respond to the Send Button</h2> + +<p>To respond to the button's on-click event, open the <code>main.xml</code> layout file and add the +<a +href="{@docRoot}reference/android/view/View.html#attr_android:onClick">{@code android:onClick}</a> +attribute to the {@link android.widget.Button <Button>} element:</p> + +<pre> +<Button android:id="@+id/button_send" + android:layout_width="wrap_content" + android:layout_height="wrap_content" + android:text="@string/button_send" + android:onClick="sendMessage" /> +</pre> + +<p>The <a +href="{@docRoot}reference/android/view/View.html#attr_android:onClick">{@code +android:onClick}</a> attribute’s value, <code>sendMessage</code>, is the name of a method in your +activity that you want to call when the user selects the button.</p> + +<p>Add the corresponding method inside the <code>MyFirstActivity</code> class:</p> + +<pre> +/** Called when the user selects the Send button */ +public void sendMessage(View view) { + // Do something in response to button +} +</pre> + +<p class="note"><strong>Tip:</strong> In Eclipse, press Ctrl + Shift + O to import missing classes +(Cmd + Shift + O on Mac).</p> + +<p>Note that, in order for the system to match this method to the method name given to <a +href="{@docRoot}reference/android/view/View.html#attr_android:onClick">{@code android:onClick}</a>, +the signature must be exactly as shown. Specifically, the method must:</p> + +<ul> +<li>Be public</li> +<li>Have a void return value</li> +<li>Have a {@link android.view.View} as the only parameter (this will be the {@link +android.view.View} that was clicked)</li> +</ul> + +<p>Next, you’ll fill in this method to read the contents of the text box and deliver that text to +another activity.</p> + + + +<h2 id="BuildIntent">Build an Intent</h2> + +<p>An {@link android.content.Intent} is an object that provides runtime binding between separate +components (such as two activities). The {@link android.content.Intent} represents an +app’s "intent to do something." You can use an {@link android.content.Intent} for a wide +variety of tasks, but most often they’re used to start another activity.</p> + +<p>Inside the {@code sendMessage()} method, create an {@link android.content.Intent} to start +an activity called {@code DisplayMessageActvity}:</p> + +<pre> +Intent intent = new Intent(this, DisplayMessageActivity.class); +</pre> + +<p>The constructor used here takes two parameters:</p> +<ul> + <li>A {@link +android.content.Context} as its first parameter ({@code this} is used because the {@link +android.app.Activity} class is a subclass of {@link android.content.Context}) + <li>The {@link java.lang.Class} of the app component to which the system should deliver +the {@link android.content.Intent} (in this case, the activity that should be started) +</ul> + +<div class="sidebox-wrapper"> +<div class="sidebox"> + <h3>Sending an intent to other apps</h3> + <p>The intent created in this lesson is what's considered an <em>explicit intent</em>, because the +{@link android.content.Intent} +specifies the exact app component to which the intent should be given. However, intents +can also be <em>implicit</em>, in which case the {@link android.content.Intent} does not specify +the desired component, but allows any app installed on the device to respond to the intent +as long as it satisfies the meta-data specifications for the action that's specified in various +{@link android.content.Intent} parameters. For more informations, see the class about <a +href="{@docRoot}training/intents/index.html">Interacting with Other Apps</a>.</p> +</div> +</div> + +<p class="note"><strong>Note:</strong> The reference to {@code DisplayMessageActivity} +will raise an error if you’re using an IDE such as Eclipse because the class doesn’t exist yet. +Ignore the error for now; you’ll create the class soon.</p> + +<p>An intent not only allows you to start another activity, but can carry a bundle of data to the +activity as well. So, use {@link android.app.Activity#findViewById findViewById()} to get the +{@link android.widget.EditText} element and add its message to the intent:</p> + +<pre> +Intent intent = new Intent(this, DisplayMessageActivity.class); +EditText editText = (EditText) findViewById(R.id.edit_message); +String message = editText.getText().toString(); +intent.putExtra(EXTRA_MESSAGE, message); +</pre> + +<p>An {@link android.content.Intent} can carry a collection of various data types as key-value +pairs called <em>extras</em>. The {@link android.content.Intent#putExtra putExtra()} method takes a +string as the key and the value in the second parameter.</p> + +<p>In order for the next activity to query the extra data, you should define your keys using a +public constant. So add the {@code EXTRA_MESSAGE} definition to the top of the {@code +MyFirstActivity} class:</p> + +<pre> +public class MyFirstActivity extends Activity { + public final static String EXTRA_MESSAGE = "com.example.myapp.MESSAGE"; + ... +} +</pre> + +<p>It's generally a good practice to define keys for extras with your app's package name as a prefix +to ensure it's unique, in case your app interacts with other apps.</p> + + +<h2 id="StartActivity">Start the Second Activity</h2> + +<p>To start an activity, you simply need to call {@link android.app.Activity#startActivity +startActivity()} and pass it your {@link android.content.Intent}.</p> + +<p>The system receives this call and starts an instance of the {@link android.app.Activity} +specified by the {@link android.content.Intent}.</p> + +<p>With this method included, the complete {@code sendMessage()} method that's invoked by the Send +button now looks like this:</p> + +<pre> +/** Called when the user selects the Send button */ +public void sendMessage(View view) { + Intent intent = new Intent(this, DisplayMessageActivity.class); + EditText editText = (EditText) findViewById(R.id.edit_message); + String message = editText.getText().toString(); + intent.putExtra(EXTRA_MESSAGE, message); + startActivity(intent); +} +</pre> + +<p>Now you need to create the {@code DisplayMessageActivity} class in order for this to +work.</p> + + + +<h2 id="CreateActivity">Create the Second Activity</h2> + +<p>In your project, create a new class file under the <code>src/<package-name>/</code> +directory called <code>DisplayMessageActivity.java</code>.</p> + +<p class="note"><strong>Tip:</strong> In Eclipse, right-click the package name under the +<code>src/</code> directory and select <strong>New > Class</strong>. +Enter "DisplayMessageActivity" for the name and {@code android.app.Activity} for the superclass.</p> + +<p>Inside the class, add the {@link android.app.Activity#onCreate onCreate()} callback method:</p> + +<pre> +public class DisplayMessageActivity extends Activity { + @Override + public void onCreate(Bundle savedInstanceState) { + super.onCreate(savedInstanceState); + } +} +</pre> + +<p>All subclasses of {@link android.app.Activity} must implement the {@link +android.app.Activity#onCreate onCreate()} method. The system calls this when creating a new +instance of the activity. It is where you must define the activity layout and where you should +initialize essential activity components.</p> + + + +<h3 id="AddToManifest">Add it to the manifest</h3> + +<p>You must declare all activities in your manifest file, <code>AndroidManifest.xml</code>, using an +<a +href="{@docRoot}guide/topics/manifest/activity-element.html">{@code <activity>}</a> element.</p> + +<p>Because {@code DisplayMessageActivity} is invoked using an explicit intent, it does not require +any intent filters (such as those you can see in the manifest for <code>MyFirstActivity</code>). So +the declaration for <code>DisplayMessageActivity</code> can be simply one line of code inside the <a +href="{@docRoot}guide/topics/manifest/application-element.html">{@code <application>}</a> +element:</p> + +<pre> +<application ... > + <activity android:name="com.example.myapp.DisplayMessageActivity" /> + ... +</application> +</pre> + +<p>The app is now runnable because the {@link android.content.Intent} in the +first activity now resolves to the {@code DisplayMessageActivity} class. If you run the app now, +pressing the Send button starts the +second activity, but it doesn't show anything yet.</p> + + +<h2 id="ReceiveIntent">Receive the Intent</h2> + +<p>Every {@link android.app.Activity} is invoked by an {@link android.content.Intent}, regardless of +how the user navigated there. You can get the {@link android.content.Intent} that started your +activity by calling {@link android.app.Activity#getIntent()} and the retrieve data contained +within it.</p> + +<p>In the {@code DisplayMessageActivity} class’s {@link android.app.Activity#onCreate onCreate()} +method, get the intent and extract the message delivered by {@code MyFirstActivity}:</p> + +<pre> +Intent intent = getIntent(); +String message = intent.getStringExtra(MyFirstActivity.EXTRA_MESSAGE); +</pre> + + + +<h2 id="DisplayMessage">Display the Message</h2> + +<p>To show the message on the screen, create a {@link android.widget.TextView} widget and set the +text using {@link android.widget.TextView#setText setText()}. Then add the {@link +android.widget.TextView} as the root view of the activity’s layout by passing it to {@link +android.app.Activity#setContentView setContentView()}.</p> + +<p>The complete {@link android.app.Activity#onCreate onCreate()} method for {@code +DisplayMessageActivity} now looks like this:</p> + +<pre> +@Override +public void onCreate(Bundle savedInstanceState) { + super.onCreate(savedInstanceState); + + // Get the message from the intent + Intent intent = getIntent(); + String message = intent.getStringExtra(MyFirstActivity.EXTRA_MESSAGE); + + // Create the text view + TextView textView = new TextView(this); + textView.setTextSize(40); + textView.setText(message); + + setContentView(textView); +} +</pre> + +<p>You can now run the app, type a message in the text box, press Send, and view the message on the +second activity.</p> + +<img src="{@docRoot}images/training/firstapp/firstapp.png" /> +<p class="img-caption"><strong>Figure 1.</strong> Both activities in the final app, running +on Android 4.0. + +<p>That's it, you've built your first Android app!</p> + +<p>To learn more about building Android apps, continue to follow the +basic training classes. The next class is <a +href="{@docRoot}training/activity-lifecycle/index.html">Managing the Activity Lifecycle</a>.</p> + + + + diff --git a/docs/html/training/tv/optimizing-layouts-tv.jd b/docs/html/training/tv/optimizing-layouts-tv.jd index 6eac6d3..e4a8e69 100644 --- a/docs/html/training/tv/optimizing-layouts-tv.jd +++ b/docs/html/training/tv/optimizing-layouts-tv.jd @@ -16,7 +16,7 @@ next.link=optimizing-navigation-tv.html <li><a href="#DesignLandscapeLayouts">Design Landscape Layouts</a></li> <li><a href="#MakeTextControlsEasyToSee">Make Text and Controls Easy to See</a></li> <li><a href="#DesignForLargeScreens">Design for High-Density Large Screens</a></li> - <li><a href="#HandleLargeBitmaps">Handle Large Bitmaps in Your Application</a></li> + <li><a href="#HandleLargeBitmaps">Design to Handle Large Bitmaps</a></li> </ol> <h2>You should also read</h2> diff --git a/docs/html/training/tv/optimizing-navigation-tv.jd b/docs/html/training/tv/optimizing-navigation-tv.jd index 8b5878e..bb78258 100644 --- a/docs/html/training/tv/optimizing-navigation-tv.jd +++ b/docs/html/training/tv/optimizing-navigation-tv.jd @@ -5,7 +5,7 @@ parent.link=index.html trainingnavtop=true previous.title=Optimizing Layouts for TV previous.link=optimizing-layouts-tv.html -next.title=Handling features not supported on TV +next.title=Handling Features Not Supported on TV next.link=unsupported-features-tv.html @jd:body |
