using javascript in android webview

You have to first register the JavaScriptInterface on your webview. JavaScriptInterFace can be a inner class as shown below. This class will have a function that you can call from html page( via javaScript ) and inside this function you can write code to change activity.

Here is the working solution for you:

public class JavascriptInterfaceActivity extends Activity {
    /** Called when the activity is first created. */


    WebView wv;

    JavaScriptInterface JSInterface;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        wv = (WebView)findViewById(R.id.webView1);

        wv.getSettings().setJavaScriptEnabled(true);
        // register class containing methods to be exposed to JavaScript

        JSInterface = new JavaScriptInterface(this);
        wv.addJavascriptInterface(JSInterface, "JSInterface"); 

        wv.loadUrl("file:///android_asset/myPage.html");

    }


    public class JavaScriptInterface {
        Context mContext;

        /** Instantiate the interface and set the context */
        JavaScriptInterface(Context c) {
            mContext = c;
        }

        @android.webkit.JavascriptInterface
        public void changeActivity()
        {
            Intent i = new Intent(JavascriptInterfaceActivity.this, nextActivity.class);
            startActivity(i);
            finish();
        }
    }
}

Here is the html page

<html>
<head>
<script type="text/javascript">
function displaymessage()
{
JSInterface.changeActivity();
}
</script>
</head>

<body>
<form>
<input type="button" value="Click me!" onclick="displaymessage()" />
</form>
</body>
</html>

Hope this helps...


You also need to add the @android.webkit.JavascriptInterface annotation on top of your changeActivity method in your android code, should you run on Android 4.2 or higher. See this link for more.