1. MessageActivity代码:
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class MessageActivity extends Activity {
private Button button01, button02, button03, button04, button05;
private TextView textView;
private Handler handler = new Handler(){
@Override
public void handleMessage(Message msg) {
// TODO Auto-generated method stub
if(msg.what == 3 || msg.what == 5){
textView.setText("what=" + msg.what + ", 这是一个空消息");
}else{
textView.setText("what=" + msg.what + "," + msg.obj.toString());
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button01 = (Button)findViewById(R.id.button01);
button02 = (Button)findViewById(R.id.button02);
button03 = (Button)findViewById(R.id.button03);
button04 = (Button)findViewById(R.id.button04);
button05 = (Button)findViewById(R.id.button05);
textView = (TextView)findViewById(R.id.textView);
button01.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
new Thread(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
Message message = Message.obtain();
message.what = 1;
message.obj = "使用Message.Obtain+Hander.sendMessage()发送消息";
handler.sendMessage(message);
}
}).start();
}
});
button02.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
new Thread(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
Message message = Message.obtain(handler);
message.what = 2;
message.obj = "使用Message.sendToTarget发送消息";
message.sendToTarget();
}
}).start();
}
});
button03.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
new Thread(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
handler.sendEmptyMessage(3);
}
}).start();
}
});
button04.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
new Thread(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
Message message = Message.obtain();
message.what = 4;
message.obj = "使用Message.Obtain+Hander.sendMessage()发送延迟消息";
handler.sendMessageDelayed(message, 3000);
}
}).start();
}
});
button05.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
new Thread(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
handler.sendEmptyMessageAtTime(5, 3000);
}
}).start();
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.message, menu);
return true;
}
}
2. main.xml代码:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<Button
android:id="@+id/button01"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/text01"/>
<Button
android:id="@+id/button02"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/text02"/>
<Button
android:id="@+id/button03"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/text03"/>
<Button
android:id="@+id/button04"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/text04"/>
<Button
android:id="@+id/button05"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/text05"/>
<TextView
android:id="@+id/textView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
3. string.xml代码:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">MessageActivity</string>
<string name="action_settings">Settings</string>
<string name="hello_world">Hello world!</string>
<string name="text01">用Handler.sendMessage发送消息</string>
<string name="text02">用Message.sendToTarget发送消息</string>
<string name="text03">发送空消息</string>
<string name="text04">用Handler.sendMessage发送延迟消息</string>
<string name="text05">发送延迟空消息</string>
</resources>