Android多线程处理机制中的Handler使用介绍

package com.example.thread;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.app.Activity;
import android.view.Menu;
import android.widget.TextView;
public class MainActivity extends Activity {
private TextView tv;
// 消息处理者
private Handler handler;
private static final int TURNTEXT = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// setContentView(R.layout.activity_main);
System.out.println("主线程----" + Thread.currentThread().getName());
tv = new TextView(this);
tv.setText("你好");
setContentView(tv);
// 处理者
handler = new Handler() {
// handlerMessage方法处理handler发送的消息
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
// msg.what操作获取发送什么消息，根据消息的标识，进行不同处理方式
int what = msg.what;
if (what == TURNTEXT) {
tv.setText(System.currentTimeMillis() + "");
}
}
};
try {
//主线程 阻塞 6s 大于
Thread.sleep(10000);
} catch (InterruptedException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
//run方法执行完毕 线程就死掉
new Thread(new Runnable() {
@Override
public void run() {
while (true) {
try {
System.out.println("子线程----"
+ Thread.currentThread().getName());
Thread.sleep(1000);
// 发送消息 what标识
handler.sendEmptyMessage(TURNTEXT);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}).start();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
package com.example.thread;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.app.Activity;
import android.view.Menu;
import android.widget.TextView;
public class MainActivity extends Activity {
private TextView tv;
// 消息处理者
private Handler handler;
private static final int TURNTEXT = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// setContentView(R.layout.activity_main);
System.out.println("主线程----" + Thread.currentThread().getName());
tv = new TextView(this);
tv.setText("你好");
setContentView(tv);
// 处理者
handler = new Handler() {
// handlerMessage方法处理handler发送的消息
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
// msg.what操作获取发送什么消息，根据消息的标识，进行不同处理方式
int what = msg.what;
if (what == TURNTEXT) {
tv.setText(System.currentTimeMillis() + "");
}
}
};
try {
//主线程 阻塞 6s 大于
Thread.sleep(10000);
} catch (InterruptedException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
//run方法执行完毕 线程就死掉
new Thread(new Runnable() {
@Override
public void run() {
while (true) {
try {
System.out.println("子线程----"
+ Thread.currentThread().getName());
Thread.sleep(1000);
// 发送消息 what标识
handler.sendEmptyMessage(TURNTEXT);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}).start();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}