当前位置：首页 > news >正文

Intent的使用

news 来源：原创 2024/5/3 18:30:12

在Android中，传递数据使用 Intent， Intent相当于各个Activity之间的桥梁，可以传递数据，可以通过 Intent启动另外一个Activity。

Intent有显式和隐式之分，显式的是直接什么要启动的组件，比如Service或者Activity，隐式的通过配置的datatype、url、action来找到匹配的组件启动。

此程序目的：

1、显式启动Activity和service

2、通过隐式的变量，启动Activity和Service

先来看先我们定义的变量类：

Java代码

package cc.androidos.intent;
public class Book {
//Intent的数据类型
public static String CONTENT_TYPE = "cc.android/intent.demo";
//Intent中的URL，这里要使用Content开头，不然会找不到组件
public static String CONTENT_URI = "content://test/";
}

package cc.androidos.intent;public class Book { //Intent的数据类型 public static  String CONTENT_TYPE = "cc.android/intent.demo";  //Intent中的URL，这里要使用Content开头，不然会找不到组件 public static String CONTENT_URI = "content://test/";}

程序主界面的代码：还有四个按钮，分别用于启动不同的组件：

Java代码

package cc.androidos.intent;
import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class IntentDemo extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button firstbtn = (Button) findViewById(R.id.firstbtn);
Button firstbtnservice = (Button) findViewById(R.id.firstbtnservice);
Button secondbtn = (Button) findViewById(R.id.secondbtn);
Button secondbtnservice = (Button) findViewById(R.id.secondbtnservice);
firstbtn.setOnClickListener(new View.OnClickListener(){
public void onClick(View v) {
//显式启动FirstIntentDemo Activity
Intent i = new Intent(getApplicationContext(),FirstIntentDemo.class);
startActivity(i);
}
});
firstbtnservice.setOnClickListener(new View.OnClickListener(){
public void onClick(View v) {
//显式启动FirstService 后台服务
Intent i = new Intent(getApplicationContext(),FirstService.class);
startService(i);
}
});
secondbtn.setOnClickListener(new View.OnClickListener(){
public void onClick(View v) {
//通过Action uri和dataype启动Activity
//程序会自动匹配到Intent-Filter配置中有(action属性)Action为Intent.ACTION_VIEW，并且数据类型（data）为cc.android/intent.demo的组件上
Intent intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.parse(Book.CONTENT_URI), Book.CONTENT_TYPE);
startActivity(intent);
}
});
secondbtnservice.setOnClickListener(new View.OnClickListener(){
public void onClick(View v) {
//通过Action uri和dataype启动Service
Intent intent = new Intent();
intent.setAction(Intent.ACTION_EDIT);
intent.setDataAndType(Uri.parse(Book.CONTENT_URI), Book.CONTENT_TYPE);
startService(intent);
}
});
}
}

package cc.androidos.intent;import android.app.Activity;import android.content.Intent;import android.net.Uri;import android.os.Bundle;import android.view.View;import android.widget.Button;public class IntentDemo extends Activity {    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);                      Button firstbtn = (Button) findViewById(R.id.firstbtn);        Button firstbtnservice = (Button) findViewById(R.id.firstbtnservice);        Button secondbtn = (Button) findViewById(R.id.secondbtn);        Button secondbtnservice = (Button) findViewById(R.id.secondbtnservice);                      firstbtn.setOnClickListener(new View.OnClickListener(){   public void onClick(View v) {    //显式启动FirstIntentDemo Activity    Intent i = new Intent(getApplicationContext(),FirstIntentDemo.class);    startActivity(i);   }        });               firstbtnservice.setOnClickListener(new View.OnClickListener(){   public void onClick(View v) {    //显式启动FirstService 后台服务    Intent i = new Intent(getApplicationContext(),FirstService.class);    startService(i);   }                 });                      secondbtn.setOnClickListener(new View.OnClickListener(){   public void onClick(View v) {        //通过Action uri和dataype启动Activity    //程序会自动匹配到Intent-Filter配置中有(action属性)Action为Intent.ACTION_VIEW，并且数据类型（data）为cc.android/intent.demo的组件上    Intent intent = new Intent();    intent.setAction(Intent.ACTION_VIEW);    intent.setDataAndType(Uri.parse(Book.CONTENT_URI), Book.CONTENT_TYPE);    startActivity(intent);   }        });        secondbtnservice.setOnClickListener(new View.OnClickListener(){   public void onClick(View v) {    //通过Action uri和dataype启动Service    Intent intent = new Intent();    intent.setAction(Intent.ACTION_EDIT);    intent.setDataAndType(Uri.parse(Book.CONTENT_URI), Book.CONTENT_TYPE);    startService(intent);   }        });           }}

以下分别是被启动的组件代码：

显式Activity和Service：

Java代码

package cc.androidos.intent;
import android.app.Activity;
import android.os.Bundle;
public class FirstIntentDemo extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.firstintent);
}
}
===============================================
package cc.androidos.intent;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.util.Log;
public class FirstService extends Service{
@Override
public IBinder onBind(Intent intent) {
return null;
}
@Override
public void onCreate() {
super.onCreate();
String tag = "First Service on Create";
Log.d(tag,"This is the first service...");
}
}

package cc.androidos.intent;import android.app.Activity;import android.os.Bundle;public class FirstIntentDemo extends Activity { @Override protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.firstintent); }}===============================================package cc.androidos.intent;import android.app.Service;import android.content.Intent;import android.os.IBinder;import android.util.Log;public class FirstService extends Service{ @Override public IBinder onBind(Intent intent) {  return null; }  @Override public void onCreate() {  super.onCreate();    String tag = "First Service on Create";  Log.d(tag,"This is the first service..."); }}

隐式启动的Activity和Service：

Java代码

package cc.androidos.intent;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
public class SecondIntentDemo extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String tag = "SecondIntentDemo onCreate..";
setContentView(R.layout.secondintent);
Intent i = getIntent();
Log.d(tag, "intent type : " + i.getType());
Log.d(tag, "intent url : " + i.getData().toString());
}
}

package cc.androidos.intent;import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.util.Log;public class SecondIntentDemo extends Activity { @Override protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  String tag = "SecondIntentDemo onCreate..";  setContentView(R.layout.secondintent);  Intent i = getIntent();  Log.d(tag, "intent type : " + i.getType());  Log.d(tag, "intent url : " + i.getData().toString()); }}

===================================

Java代码

package cc.androidos.intent;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.util.Log;
public class SecondService extends Service {
@Override
public IBinder onBind(Intent arg0) {
return null;
}
@Override
public void onCreate() {
super.onCreate();
String tag = "Second service ";
Log.d(tag, "Startup second service... ");
}
}

package cc.androidos.intent;import android.app.Service;import android.content.Intent;import android.os.IBinder;import android.util.Log;public class SecondService extends Service { @Override public IBinder onBind(Intent arg0) {  return null; }  @Override public void onCreate() {  super.onCreate();  String tag = "Second service ";  Log.d(tag, "Startup second service... "); }}

AndroidManifest.xml文件配置：

这个很重要，需要配置好才行，不然会出现AcitvityNotFoundException

Xml代码

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="cc.androidos.intent"
android:versionCode="1"
android:versionName="1.0.0">
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name=".IntentDemo"
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=".FirstIntentDemo" android:label="@string/app_name">
</activity>
<activity android:name=".SecondIntentDemo" android:label="@string/app_name">
<intent-filter >
<action android:name="android.intent.action.VIEW"/>
<data android:mimeType="cc.android/intent.demo"/>
<category android:name="android.intent.category.DEFAULT"/>
</intent-filter>
</activity>
<service android:name=".FirstService" >
</service>
<service android:name=".SecondService" >
<intent-filter >
<action android:name="android.intent.action.EDIT"/>
<data android:mimeType="cc.android/intent.demo"/>
<category android:name="android.intent.category.DEFAULT"/>
</intent-filter>
</service>
</application>
</manifest>

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"      package="cc.androidos.intent"      android:versionCode="1"      android:versionName="1.0.0">    <application android:icon="@drawable/icon" android:label="@string/app_name">        <activity android:name=".IntentDemo"                  android:label="@string/app_name">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>               <!-- First Intent Demo  -->        <activity android:name=".FirstIntentDemo"  android:label="@string/app_name">        </activity>                      <!-- Second Intent Demo  -->          <activity android:name=".SecondIntentDemo"  android:label="@string/app_name">         <intent-filter >         <!--The intent filter parameters must match the intent datatype(mimeType) \ action  -->          <action android:name="android.intent.action.VIEW"/>          <data android:mimeType="cc.android/intent.demo"/>          <category android:name="android.intent.category.DEFAULT"/>         </intent-filter>        </activity>                      <service android:name=".FirstService" >        </service>                <service android:name=".SecondService" >          <intent-filter >           <!--The intent filter parameters must match the intent datatype(mimeType) \ action  -->           <action android:name="android.intent.action.EDIT"/>          <data android:mimeType="cc.android/intent.demo"/>          <category android:name="android.intent.category.DEFAULT"/>          </intent-filter>                  </service>                  </application></manifest>