Android Tutorial => Communication from Javascript to Java (Android)

Example

Android Activity

package com.example.myapp;

import android.os.Bundle;
import android.app.Activity;
import android.webkit.WebView;

public class WebViewActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    
        WebView webView = new WebView(this);
        setContentView(webView);

       /* 
        *   Note the label Android, this is used in the Javascript side of things
        *   You can of course change this.
        */
        webView.addJavascriptInterface(new JavascriptHandler(), "Android");
    
        webView.loadUrl("http://example.com");
    }
}

Java Javascript Handler

import android.webkit.JavascriptInterface;

public class JavascriptHandler {

    /**
     *  Key point here is the annotation @JavascriptInterface
     *
     */
    @JavascriptInterface
    public void jsCallback() {
       // Do something
    }

    @JavascriptInterface
    public void jsCallbackTwo(String dummyData) {
       // Do something
    }
}

Web Page, Javascript call

<script>
... 
Android.jsCallback();
...
Android.jsCallback('hello test');
...
</script>

Extra Tip

Passing in a complex data structure, a possible solution is use JSON.

Android.jsCallback('{ "fake-var" : "fake-value", "fake-array" : [0,1,2] }');

On the Android side use your favorite JSON parser ie: JSONObject

PDF - Download Android for free

Previous Next

Android

Fastest Entity Framework Extensions

Example

Got any Android Question?

Android

Android WebView Communication from Javascript to Java (Android)

Fastest Entity Framework Extensions

Example

Got any Android Question?