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diff --git a/docs/html/resources/articles/layout-tricks-reuse.jd b/docs/html/resources/articles/layout-tricks-reuse.jd deleted file mode 100644 index 179c1d8..0000000 --- a/docs/html/resources/articles/layout-tricks-reuse.jd +++ /dev/null @@ -1,81 +0,0 @@ -page.title=Layout Tricks: Creating Reusable UI Components -parent.title=Articles -parent.link=../browser.html?tag=article -@jd:body - -<p>The Android platform offers a wide variety of UI <em>widgets</em>, small -visual construction blocks that you can glue together to present users with -complex and useful interfaces. However applications often need higher-level -visual <em>components</em>. To meet that need, and to do so efficiently, you can -combine multiple standard widgets into a single, reusable component. </p> - -<p>For example, you could create a reusable component that contains a progress -bar and a cancel button, a panel containing two buttons (positive and negative -actions), a panel with an icon, a title and a description, and so on. You can -create UI components easily by writing a custom <code>View</code>, but you can -do it even more easily using only XML.</p> - -<p>In Android XML layout files, each tag is mapped to an actual class instance -(the class is always a subclass of {@link android.view.View} The UI toolkit lets -you also use three special tags that are not mapped to a <code>View</code> -instance: <code><requestFocus /></code>, <code><merge /></code> and -<code><include /></code>. This article shows how to use <code><include -/></code> to create pure XML visual components. For information about how to -use <code><merge /></code>, which can be particularly powerful when -combined with <code><include /></code>see the <a -href="{@docRoot}resources/articles/layout-tricks-merge.html">Merging Layouts</a> -article. </p> - -<p>The <code><include /></code> element does exactly what its name -suggests; it includes another XML layout. Using this tag is straightforward as -shown in the following example, taken straight from <a -href="http://android.git.kernel.org/?p=platform/packages/apps/Launcher.git;a= -tree;h=refs/heads/master;hb=master">the source code of the Home application</a> -that ships with Android:</p> - -<pre class="prettyprint"><com.android.launcher.Workspace - android:id="@+id/workspace" - android:layout_width="fill_parent" - android:layout_height="fill_parent" - - launcher:defaultScreen="1"> - - <include android:id="@+id/cell1" layout="@layout/workspace_screen" /> - <include android:id="@+id/cell2" layout="@layout/workspace_screen" /> - <include android:id="@+id/cell3" layout="@layout/workspace_screen" /> - -</com.android.launcher.Workspace></pre> - -<p>In the <code><include /></code> only the <code>layout</code> attribute -is required. This attribute, without the <code>android</code> namespace prefix, -is a reference to the layout file you wish to include. In this example, the same -layout is included three times in a row. This tag also lets you override a few -attributes of the included layout. The above example shows that you can use -<code>android:id</code> to specify the id of the root view of the included -layout; it will also override the id of the included layout if one is defined. -Similarly, you can override all the layout parameters. This means that any -<code>android:layout_*</code> attribute can be used with the <code><include -/></code> tag. Here is an example in -which the same layout is included twice, but only the first one overrides the layout properties:</p> - -<pre> -<!-- override the layout height and width --> -<include layout="@layout/image_holder" - android:layout_height="fill_parent" - android:layout_width="fill_parent" /> -<!-- do not override layout dimensions; inherit them from image_holder --> -<include layout="@layout/image_holder" /> -</pre> - -<p class="caution"><strong>Caution:</strong> If you want to override the layout dimensions, -you must override both <code>android:layout_height</code> and -<code>android:layout_width</code>—you cannot override only the height or only the width. -If you override only one, it will not take effect. (Other layout properties, such as weight, -are still inherited from the source layout.)</p> - -<p>This tag is particularly useful when you need to customize only part of your -UI depending on the device's configuration. For instance, the main layout of -your activity can be placed in the <code>layout/</code> directory and can -include another layout which exists in two flavors, in <code>layout-land/</code> -and <code>layout-port/</code>. This allows you to share most of the UI in -portrait and landscape.</p>
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