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diff --git a/docs/html/guide/tutorials/views/hello-webview.jd b/docs/html/guide/tutorials/views/hello-webview.jd deleted file mode 100644 index a927b04..0000000 --- a/docs/html/guide/tutorials/views/hello-webview.jd +++ /dev/null @@ -1,118 +0,0 @@ -page.title=Hello, WebView -parent.title=Hello, Views -parent.link=index.html -@jd:body - -<p>A {@link android.webkit.WebView} allows you to create your own web browser Activity. In this tutorial, -we'll create a simple Activity that can view web pages.</p> - -<ol> - <li>Create a new project/Activity called HelloWebView.</li> - <li>Open the layout file. Insert a WebView so it looks like so: -<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="vertical"> - - <WebView - android:id="@+id/webview" - android:layout_width="fill_parent" - android:layout_height="fill_parent" - /> - -</LinearLayout> -</pre></li> - - <li>Now open the HelloWebView.java file. - At the top of the class, instantiate a WebView object: -<pre>WebView webview;</pre> - <p> Then add the following at the end of the <code>onCreate()</code> method:</p> -<pre> -webview = (WebView) findViewById(R.id.webview); -webview.getSettings().setJavaScriptEnabled(true); -webview.loadUrl("http://www.google.com"); -</pre> - - <p>This captures the WebView we created in our layout, then requests a - {@link android.webkit.WebSettings} object and enables JavaScript. - Then we load a URL.</p></li> - - <li>Because we're accessing the internet, we need to add the appropriate - permissions to the Android manifest file. So open the AndroidManifest.xml file - and, add the following as a child of the <code><manifest></code> element: - - <pre><uses-permission android:name="android.permission.INTERNET" /></pre></li> - - <li>Now run it.</li> -</ol> -<p> You now have the world's simplest web page viewer. - It's not quite a browser yet. It only loads the page we've requested.</p> - -<hr/> - -<p>We can load a page, but as soon as we click a link, the default Android web browser -handles the Intent, instead of our own WebView handling the action. So now we'll -override the {@link android.webkit.WebViewClient} to enable us to handle our own URL loading.</p> - -<ol> - <li>In the HelloAndroid Activity, add this nested private class: -<pre> -private class HelloWebViewClient extends WebViewClient { - @Override - public boolean shouldOverrideUrlLoading(WebView view, String url) { - view.loadUrl(url); - return true; - } -}</pre></li> - - <li>Now, in the <code>onCreate()</code> method, set an instance of the <code>HelloWebViewClient</code> - as our WebViewClient: - <pre>webview.setWebViewClient(new HelloWebViewClient());</pre> - - <p>This line should immediately follow the initialization of our WebView object.</p> - <p>What we've done is create a WebViewClient that will load any URL selected in our -WebView in the same WebView. You can see this in the <code>shouldOverrideUrlLoading()</code> -method, above—it is passed the current WebView and the URL, so all we do -is load the URL in the given view. Returning <var>true</var> says that we've handled the URL -ourselves and the event should not bubble-up.</p> - <p>If you try it again, new pages will now load in the HelloWebView Activity. However, you'll notice that -we can't navigate back. We need to handle the back button -on the device, so that it will return to the previous page, rather than exit the application.</p> - </li> - - <li>To handle the back button key press, add the following method inside the HelloWebView -Activity: -<pre> -@Override -public boolean onKeyDown(int keyCode, KeyEvent event) { - if ((keyCode == KeyEvent.KEYCODE_BACK) && webview.canGoBack()) { - webview.goBack(); - return true; - } - return super.onKeyDown(keyCode, event); -}</pre> - <p>The condition uses a {@link android.view.KeyEvent} to check - whether the key pressed is the BACK button and whether the - WebView is actually capable of navigating back (if it has a history). If both are - <em>not</em> true, then we send the event up the chain (and the Activity will close). - But if both <em>are</em> true, then we call <code>goBack()</code>, - which will navigate back one step in the history. We then return true to indicate - that we've handled the event.</p> -</li> -</ol> -<p>When you open the application, it should look like this:</p> -<img src="images/hello-webview.png" width="150px" /> - -<h3>Resource</h3> -<ul> -<li>{@link android.webkit.WebView}</li> -<li>{@link android.webkit.WebViewClient}</li> -<li>{@link android.view.KeyEvent}</li> -</ul> - - - - - |