Android Development: About WebView

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WebView (network view) can load a display page, which can be viewed as a browser. It uses the WebKit rendering engine to load the Display Web page, implementing the WebView in the following two different ways:

Steps for the first method:

1. Instantiate the WebView component in the activity to: WebView WebView = new WebView (this);

2. Call WebView's Loadurl () method, set Wevview to display the Web page: Internet: Webview.loadurl ("http://www.google.com"); For local files: Webview.loadurl ("file:///android_asset/XX.html"); Local files are stored in the: Assets file

3. Call the activity's Setcontentview( ) method to display the page view

4. Use WebView point link to see a lot of pages later in order to let WebView support fallback function, need to overwrite the Activity class onkeydown () method, if do not do any processing, click the system fallback shear key, the entire browser will call finish () and end itself, Instead of retreating back to the previous page

5. You need to add permissions to the Androidmanifest.xml file, or the Web page not available error will occur. <uses-permission android:name="Android.permission.INTERNET" />

Here is a concrete example:

Mainactivity.java

2. Package com.android.webview.activity;
6. Import android.app.Activity;
8. Import Android.os.Bundle;
10. Import android.view.KeyEvent;
12. Import Android.webkit.WebView;
16. Public class Mainactivity extends Activity {
18. private WebView WebView;
20. @Override
22. public void OnCreate (Bundle savedinstancestate) {
24. super.oncreate (savedinstancestate);
26. //Instantiate WebView object
28. WebView = New WebView (this);
30. //Set the WebView property to be able to execute JavaScript scripts
32. Webview.getsettings (). setjavascriptenabled (true);
34. //Load the Web page that needs to be displayed
36. Webview.loadurl ("http://www.51cto.com/");
38. //Set up Web View
40. Setcontentview (WebView);
42. }
46. @Override
48. //Set fallback
50. //onkeydown (int keycoder,keyevent event) method covering activity class
52. Public boolean onKeyDown (int keycode, keyevent event) {
54. if ((keycode = = keyevent.keycode_back) && webview.cangoback ()) {
56. Webview.goback (); //goback () indicates that the previous page of the WebView is returned
58. return true;
60. }
62. return false;
64. }

Add permissions to 17 rows in the Androidmanifest.xml file

2. <? XML version= "1.0" encoding="Utf-8"?>
4. <manifest xmlns:android="http://schemas.android.com/apk/res/android"
6. package="Com.android.webview.activity"
8. android:versioncode="1"
10. Android:versionname="1.0">
12. <uses-sdk android:minsdkversion="ten" />
16. <application android:icon="@drawable/icon" android:label="@string/app_name">
18. <activity android:name=". Mainactivity "
20. Android:label="@string/app_name">
22. <intent-filter>
24. <action android:name="Android.intent.action.MAIN" />
26. <category android:name="Android.intent.category.LAUNCHER" />
28. </intent-filter>
30. </activity>
32. </Application>
34. <uses-permission android:name="Android.permission.INTERNET"/>
36. </manifest>

：

Steps for the second method:

1. Declare webview in the layout file

2, in the activity of the instantiation of WebView

3, call WebView Loadurl () method, set Wevview to display the page

4. To enable WebView to respond to hyperlinks, call the Setwebviewclient () method to set the WebView view

5, with WebView point link to see a lot of pages later in order to let WebView support fallback function, need to overwrite the Activity class onkeydown () method, if do not do any processing, click the system fallback shear key, the entire browser will call finish () and end itself, Instead of retreating back to the previous page

6. You need to add permissions to the Androidmanifest.xml file, or the Web page not available error occurs.

<uses-permission android:name= "Android.permission.INTERNET"/>

Here's a concrete example:

Mainactivity.java

2. Package com.android.webview.activity;
6. Import android.app.Activity;
8. Import Android.os.Bundle;
10. Import android.view.KeyEvent;
12. Import Android.webkit.WebView;
14. Import android.webkit.WebViewClient;
18. Public class Mainactivity extends Activity {
20. private WebView WebView;
22. @Override
24. public void OnCreate (Bundle savedinstancestate) {
26. super.oncreate (savedinstancestate);
28. Setcontentview (R.layout.main);
30. WebView = (webview) Findviewbyid (R.id.webview);
32. //Set the WebView property to be able to execute JavaScript scripts
34. Webview.getsettings (). setjavascriptenabled (true);
36. //Load the Web page that needs to be displayed
38. Webview.loadurl ("http://www.51cto.com/");
40. //Set up Web View
42. Webview.setwebviewclient (new Hellowebviewclient ());
44. }
48. @Override
50. //Set fallback
52. //onkeydown (int keycoder,keyevent event) method covering activity class
54. Public boolean onKeyDown (int keycode, keyevent event) {
56. if ((keycode = = keyevent.keycode_back) && webview.cangoback ()) {
58. Webview.goback (); //goback () indicates that the previous page of the WebView is returned
60. return true;
62. }
64. return false;
66. }
70. //web View
72. private class Hellowebviewclient extends Webviewclient {
74. @Override
76. Public Boolean shouldoverrideurlloading (WebView view, String URL) {
78. View.loadurl (URL);
80. return true;
82. }
84. }
86. }

Main.xml

2. <? XML version= "1.0" encoding="Utf-8"?>
4. <linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
6. android:orientation="vertical"
8. android:layout_width="fill_parent"
10. android:layout_height="fill_parent"
12. >
14. <WebView
16. android:id="@+id/webview"
18. android:layout_width="fill_parent"
20. android:layout_height="fill_parent"
22. />
24. </linearlayout>

Add permissions to 17 rows in the Androidmanifest.xml file

2. <? XML version= "1.0" encoding="Utf-8"?>
4. <manifest xmlns:android="http://schemas.android.com/apk/res/android"
6. package="com.android.webview.activity"
8. android:versioncode="1"
10. android:versionname="1.0">
12. <uses-sdk android:minsdkversion="ten" />
16. <application android:icon="@drawable/icon" android:label="@string/app_name">
18. <activity android:name=". Mainactivity "
20. android:label="@string/app_name">
22. <intent-filter>
24. <action android:name="Android.intent.action.MAIN" />
26. <category android:name="Android.intent.category.LAUNCHER" />
28. </intent-filter>
30. </Activity>
32. </Application>
34. <uses-permission android:name="Android.permission.INTERNET"/>
36. </manifest>

：

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Android Development: About WebView