Android组件之间的信使intent
目标组件要通过intent来声明自己的条件,一般通过组件中的<intent-filter>元素来实现。
intent可以启动Activity(startActivity()、startActivityForResult())、Service(startService()、bindService())、Broadcasts(sendBroadcast()、sendOrderedBroadcast()、sendStickyBroadcast())。有以下部分组成:动作Action、数据data、分类Category、类型Type、组件Component、扩展信息Extra。
1、工程目录
2、MainActivity.java
package com.example.test_intent_componentname;
import android.os.Bundle;
import android.app.Activity;
import android.content.ComponentName;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
private Button myBtn;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myBtn = (Button) findViewById(R.id.button01);
myBtn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
// 实例化组件名称(这里要细化到activity,不然出错ActivityNotFoundException)
ComponentName cn = new ComponentName(MainActivity.this,
"com.example.myactivity.MyActivity");
// 实例化intent
Intent intent = new Intent();
// 为intent设置组件名称属性
intent.setComponent(cn);
// 启动Activity
startActivity(intent);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
MyActivity.java
package com.example.myactivity;
import com.example.test_intent_componentname.R;
import android.app.Activity;
import android.content.ComponentName;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
public class MyActivity extends Activity{
private TextView myTextview;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.mylayout);
myTextview=(TextView)findViewById(R.id.textview02);
//获得intent
Intent intent = this.getIntent();
//获得组件名称
ComponentName cn = intent.getComponent();
//获得包名称
String packagename = cn.getPackageName();
//获得类名称
String classname = cn.getClassName();
myTextview.setText("z组件包名称:"+packagename+"组件类名称:"+classname);
}
}
3、布局文件
main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<Button
android:id="@+id/button01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="intent组件名称测试" />
</LinearLayout>
myactivity.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/textview02"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>
4、注册Activity
5、结果演示