am 1e94db6e: am 3341bde3: am fc677afe: Merge "docs: update webview guide with...

<p>For example, you can include the following class in your Android application:</p>

<pre>

public class JavaScriptInterface {

public class WebAppInterface {

    Context mContext;

    /** Instantiate the interface and set the context */

    }

    /** Show a toast from the web page */

    @JavascriptInterface

    public void showToast(String toast) {

        Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();

    }

}

</pre>

<p>In this example, the {@code JavaScriptInterface} class allows the web page to create a {@link

<p class="caution"><strong>Caution:</strong> If you've set either your <a

href="{@docRoot}guide/topics/manifest/uses-sdk-element.html#min">{@code minSdkVersion}</a> or <a

href="{@docRoot}guide/topics/manifest/uses-sdk-element.html#target">{@code targetSdkVersion}</a>

to 17 or higher, <strong>you

must add the {@code &#64;JavascriptInterface} annotation</strong> to any method that you want

available your web page code (the method must also be public). If you do not provide the

annotation, then the method will not accessible by your web page when running on Android 4.2 or

higher.</p>

<p>In this example, the {@code WebAppInterface} class allows the web page to create a {@link

android.widget.Toast} message, using the {@code showToast()} method.</p>

<p>You can bind this class to the JavaScript that runs in your {@link android.webkit.WebView} with

<pre>

WebView webView = (WebView) findViewById(R.id.webview);

webView.addJavascriptInterface(new JavaScriptInterface(this), "Android");

webView.addJavascriptInterface(new WebAppInterface(this), "Android");

</pre>

<p>This creates an interface called {@code Android} for JavaScript running in the {@link

android.webkit.WebView}. At this point, your web application has access to the {@code

JavaScriptInterface} class. For example, here's some HTML and JavaScript that creates a toast

WebAppInterface} class. For example, here's some HTML and JavaScript that creates a toast

message using the new interface when the user clicks a button:</p>

<pre>

<p>There's no need to initialize the {@code Android} interface from JavaScript. The {@link

android.webkit.WebView} automatically makes it

available to your web page. So, at the click of the button, the {@code showAndroidToast()}

function uses the {@code Android} interface to call the {@code JavaScriptInterface.showToast()}

function uses the {@code Android} interface to call the {@code WebAppInterface.showToast()}

method.</p>

<p class="note"><strong>Note:</strong> The object that is bound to your JavaScript runs in