The way to implement JavaScript invoke Java classes in WebView in Android _android

To facilitate interaction between Web pages and Android apps, the Android system provides a mechanism for invoking Java class methods in WebView JavaScript Web scripts. You can map a Java object to a JavaScript object as long as you call the Addjavascriptinterface method.

1. Mapping Java objects to JavaScript objects

Copy Code code as follows:

Mwebview = (webview) Findviewbyid (r.id.wv_content);
Mwebview.setverticalscrollbaroverlay (TRUE);
Final websettings settings = Mwebview.getsettings ();
Settings.setsupportzoom (TRUE);

WebView Enable JavaScript script execution
Settings.setjavascriptenabled (TRUE);
Settings.setjavascriptcanopenwindowsautomatically (TRUE);

Map Java objects to a JavaScript object named "Js2java"
Methods for invoking Java objects through "Window.js2java" in JavaScript
Mwebview.addjavascriptinterface (New Jsinvokeclass (), "Js2java");

Copy Code code as follows:

/** Web page JavaScript invoke interface **/
Class Jsinvokeclass {
public void back () {
Activity.finish ();
}
}

2. JavaScript invoke Java Object Example

Invoke the back method of the above Jsinvokeclass class object, as follows:

Copy Code code as follows:

Window.js2java.back ();