Android 中线程网络超时的处理
Android开发中经常需要调用线程访问网络，而手机的网络信号经常断断续续，容易出现网络超时的情况，这种情况下后台线程往往得不到关闭，浪费系统资源。在下面的例子中使用了java 中的Timer类，对线程进行了约束，如果线程在一定时间内为响应则终止该线程。
package com.zf.thread_test;
import java.util.Timer;
import java.util.TimerTask;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.app.Activity;
import android.app.ProgressDialog;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
public class MainActivity extends Activity {
private static final int TIME_OUT = 0;
private static final int SUCCESS = 1;
// 超时的时限为5秒
private static final int TIME_LIMIT = 5000;
ProgressDialog proDialog;
Timer timer;
Thread thread;
Button btn1, btn2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn1 = (Button) findViewById(R.id.button1);
btn2 = (Button) findViewById(R.id.button2);
// 测试未超时的线程，为btn1绑定事件
btn1.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
proDialog = ProgressDialog.show(MainActivity.this, "提示",
"线程运行中");
// 匿名内部线程
thread = new Thread() {
@Override
public void run() {
while (true) {
try {
//线程休眠时间，超时
sleep(10000);
} catch (InterruptedException e) {
break;
}
}
}
};
thread.start();
// 设定定时器
timer = new Timer();
timer.schedule(new TimerTask() {
@Override
public void run() {
sendTimeOutMsg();
}
}, TIME_LIMIT);
}
});
// 测试超时的线程,为btn2绑定事件
btn2.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
proDialog = ProgressDialog.show(MainActivity.this, "提示",
"线程运行中");
// 匿名内部线程
thread = new Thread() {
public void run() {
try {
// 线程休眠时间，未超时
Thread.sleep(3000);
} catch (InterruptedException e) {
e.printStackTrace();
}
Message msgSuc = new Message();
msgSuc.what = SUCCESS;
myHandler.sendMessage(msgSuc);
}
};
thread.start();
// 设定定时器
timer = new Timer();
timer.schedule(new TimerTask() {
@Override
public void run() {
sendTimeOutMsg();
}
}, TIME_LIMIT);
}
});
}
// 接收消息的Handler
final Handler myHandler = new Handler() {
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case TIME_OUT:
//打断线程
thread.interrupt();
proDialog.dismiss();
Toast.makeText(MainActivity.this, "线程超时", Toast.LENGTH_SHORT)
.show();
break;
case SUCCESS:
//取消定时器
timer.cancel();
proDialog.dismiss();
Toast.makeText(MainActivity.this, "线程运行完成", Toast.LENGTH_SHORT)
.show();
break;
default:
break;
}
};
};
//向handler发送超时信息
private void sendTimeOutMsg() {
Message timeOutMsg = new Message();
timeOutMsg.what = TIME_OUT;
myHandler.sendMessage(timeOutMsg);
}
}
补充：移动开发 , Android ,
