In Android through the WebView control, you can implement the page to be loaded with the Android method call each other, we want to implement the Addjavascriptinterface method in WebView, so that HTML can call the Android method, I personally feel a bit like dwr here.
To make it easy for everyone to understand, I wrote a simple demo with the following steps:
First step: Create a new Android project named Webviewdemo (here I have an HTML page defined in assets).
The second step: Modify the Main.xml layout file, add a WebView control and a button control, the code is as follows:
<?xml version= "1.0" encoding= "Utf-8"?> <linearlayout xmlns:android= "Http://schemas.android.com/apk/res/android"android:orientation= "Vertical"Android:layout_width= "Fill_parent"Android:layout_height= "Fill_parent" > <TextView android:layout_width= "Fill_parent"Android:layout_height= "Wrap_content"Android:text= "Welcome to Mr Wei ' s Blog." /> <WebView Android:id= "@+id/webview"Android:layout_width= "Fill_parent"Android:layout_height= "Wrap_content"/> <Button Android:id= "@+id/button"Android:layout_width= "Fill_parent"Android:layout_height= "Wrap_content"Android:text= "Change the WebView content"/> </LinearLayout>
The third step: Create a new demo.html file in the assets directory, the code is as follows (I do not know why the more MCE: These things,<script></script> this is right):
function fillcontent () { document.getElementById ("content"). InnerHTML = "This content was showed by Android invoke Javascript function." ; } // --></mce:script> <body> <p><a onclick= "Window.demo.startMap ()" href= "" >start googlemap</a></p> <p id= "content" ></p> <p>a Demo----Android and Javascript invoke each other.</p> <p>Author:Frankiewei</p> </body>Fourth step: Modify the main core program Webviewdemo.java, the code is as follows:
PackageCom.tutor.webwiewdemo; Importandroid.app.Activity; ImportAndroid.content.ComponentName; Importandroid.content.Intent; ImportAndroid.os.Bundle; ImportAndroid.view.View; Importandroid.webkit.WebSettings; ImportAndroid.webkit.WebView; ImportAndroid.widget.Button; Public classWebviewdemoextendsActivity {PrivateWebView Mwebview; PrivateButton Mbutton; Public voidonCreate (Bundle savedinstancestate) {Super. OnCreate (savedinstancestate); Setcontentview (R.layout.main); Setupviews (); } //Initialize Private voidsetupviews () {Mwebview=(WebView) Findviewbyid (R.id.webview); WebSettings mwebsettings=mwebview.getsettings (); //Add this sentence to use the JavaScript methodMwebsettings.setjavascriptenabled (true); //add an interface method to make the HTML page callMwebview.addjavascriptinterface (NewObject () {//Here I define a way to open the map app Public voidStartmap () {Intent mintent=NewIntent (); ComponentName Component=NewComponentName ("Com.google.android.apps.maps", "Com.google.android.maps.MapsActivity"); Mintent.setcomponent (component); StartActivity (mintent); } }, "Demo"); //Load PageMwebview.loadurl ("file:///android_asset/demo.html"); Mbutton=(Button) Findviewbyid (R.id.button); //Add an event response to the button, execute the JavaScript fillcontent () methodMbutton.setonclicklistener (NewButton.onclicklistener () { Public voidOnClick (View v) {Mwebview.loadurl ("Javascript:fillcontent ()"); } }); } }Fifth step: Run the above project to see the effect.
The HTML content changes when the button is clicked on the first interface
Click the HTML Startgooglemap to launch the map app
Android Master Advanced Tutorials (20)---Android and JavaScript methods call each other!
Start building with 50+ products and up to 12 months usage for Elastic Compute Service
1 on 1 presale consultation
24/7 Technical Support 6 Free Tickets per Quarter Faster Response
Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.
A comprehensive suite of global cloud computing services to power your business
Payment Methods We Support
