simpleton/Webview_bridge_JS.java

## test.html
//html code
<html>
<head>
    <script type="text/javascript">
        function ClientSideMethod(message){
            var x=document.getElementById("te");
                  x.innerHTML = message;
        }
    </script>
</head>
<body>
    <div id="te"></div>
    <button onClick="ClientSideMethod('client side method called')"> Call Javascript Method </button>
    <button onClick="testClick('Hello aaa');">Call Java Activity Method</button>
</body>
</html>

## Webview_bridge_JS.java
//java code
public class MainActivity extends Activity {
  private WebView webView;
	private static final String TAG = "MainActivity";
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

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

		// requires javascript
		this.webView.getSettings().setJavaScriptEnabled(true);

		// set the html view to load
		this.webView.loadUrl("file:///android_asset/test.html");

		// make this activity accessible to javascript
		this.webView.addJavascriptInterface(this, "activity");

		this.webView.loadUrl("javascript:function testClick(aa) {var x=document.getElementById(\"te\");x.innerHTML = aa;activity.TestMethod(aa);}");

	}

	@JavascriptInterface
    public void TestMethod(String aa)
    {
          Log.e(TAG, "TestMethod: " + aa);
    }
}
	//html code
	<html>
	<head>
	<script type="text/javascript">
	function ClientSideMethod(message){
	var x=document.getElementById("te");
	x.innerHTML = message;
	}
	</script>
	</head>
	<body>
	<div id="te"></div>
	<button onClick="ClientSideMethod('client side method called')"> Call Javascript Method </button>
	<button onClick="testClick('Hello aaa');">Call Java Activity Method</button>
	</body>
	</html>
	//java code
	public class MainActivity extends Activity {
	private WebView webView;
	private static final String TAG = "MainActivity";
	@Override
	protected void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);
	setContentView(R.layout.activity_main);

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

	// requires javascript
	this.webView.getSettings().setJavaScriptEnabled(true);

	// set the html view to load
	this.webView.loadUrl("file:///android_asset/test.html");

	// make this activity accessible to javascript
	this.webView.addJavascriptInterface(this, "activity");

	this.webView.loadUrl("javascript:function testClick(aa) {var x=document.getElementById(\"te\");x.innerHTML = aa;activity.TestMethod(aa);}");

	}

	@JavascriptInterface
	public void TestMethod(String aa)
	{
	Log.e(TAG, "TestMethod: " + aa);
	}
	}