06_intent and intentfilter

Intent is a medium for message transmission between components in the same or different applications. It is an abstract description of the action to be executed and is generally used as a parameter.

 

Intent describes the basic components to be started;

Intentfilter filters components.

 

The following code uses intent to enable the activity, open an image, call 10086, and open a webpage.

 

Package COM. example. intentdemo; import Java. io. file; import android. support. v7.app. actionbaractivity; import android. view. view; import android. content. intent; import android.net. uri; import android. OS. bundle; public class mainactivity extends actionbaractivity {@ override protected void oncreate (bundle savedinstancestate) {super. oncreate (savedinstancestate); setcontentview (R. layout. activity_main); findviewbyid (R. id. btnstartaty1 ). setonclicklistener (new view. onclicklistener () {@ override public void onclick (view v) {// explicitly intent // intent I = new intent (); // I. setcomponent (New componentname ("com. example. intentdemo "," com. example. intentdemo. aty1 "); // start with an action, started by the operating system // implicit intent I = new intent (" com. example. intentdemo. intent. action. ayt1 "); startactivity (I) ;}}); findviewbyid (R. id. btnopenimage ). setonclicklistener (new view. onclicklistener () {@ override public void onclick (view v) {file F = new file ("/storage/emulated/0/pictures/screenshots/Screenshot_2014-08-30-08-08-10.png "); intent I = new intent (intent. action_view); I. setdataandtype (URI. fromfile (F), "image/*"); startactivity (I) ;}}); findviewbyid (R. id. btndel10086 ). setonclicklistener (new view. onclicklistener () {@ override public void onclick (view v) {intent I = new intent (intent. action_view); I. setdata (URI. parse ("Tel: 10086"); startactivity (I) ;}}); findviewbyid (R. id. btnopenbaidu ). setonclicklistener (new view. onclicklistener () {@ override public void onclick (view v) {intent I = new intent (intent. action_view, Uri. parse ("http://www.baidu.com"); startactivity (I );}});}}

Manifest file:

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.example.intentdemo"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk        android:minSdkVersion="8"        android:targetSdkVersion="19" />    <application        android:allowBackup="true"        android:icon="@drawable/ic_launcher"        android:label="@string/app_name"        android:theme="@style/AppTheme" >        <activity            android:name="com.example.intentdemo.MainActivity"            android:label="@string/app_name" >            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity><activity android:name="Aty1">            <intent-filter>                <category android:name="android.intent.category.DEFAULT" /><action android:name="com.example.intentdemo.intent.action.Ayt1" />                            </intent-filter>        </activity>                <activity android:name="ImageViewer">                        <intent-filter >                                <action android:name="android.intent.action.view"/>                <category android:name="android.intent.category.DEFAULT"/>                <data android:mimeType="image/*" android:scheme="file"/>                            </intent-filter>                    </activity>    </application></manifest>

 

06_intent and intentfilter