方式一、使用Timer(定時器)和TimerTask實現
示例代碼：
public class MainActivity extends Activity {
private TextView msg;
final Handler handler = new Handler() {
public void handleMessage(Message msg) {
switch (msg.what) {
case 1:
update();
break;
}
super.handleMessage(msg);
}
void update() {
//刷新msg的內容
}
};
Timer timer = new Timer();
TimerTask task = new TimerTask() {
public void run() {
Message message = new Message();
message.what = 1;
handler.sendMessage(message);
}
};
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
msg = (TextView) findViewById(R.id.txtMsg);
msg.setText("你好啊！");
timer.schedule(task, 1000 * 40, 1000 * 30); //啓動timer
}
@Override
protected void onDestroy() {
if (timer != null) {// 停止timer
timer.cancel();
timer = null;
}
super.onDestroy();
}
}
方式二、使用Runnable和Handler
示例代碼
public class MainActivity extends Activity {
private TextView msg;
private Handler handler = new Handler();
private Runnable runnable = new Runnable() {
public void run() {
this.update();
handler.postDelayed(this, 1000 * 120);// 間隔120秒
}
void update() {
//刷新msg的內容
}
};
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
msg = (TextView) findViewById(R.id.txtMsg);
msg.setText("你好啊！");
handler.postDelayed(runnable, 1000 * 60);
}
@Override
protected void onDestroy() {
handler.removeCallbacks(runnable); //停止刷新
super.onDestroy();
}
}
第一種方式還適用於消息通知的方式實現更新，第二種方式通常是主動去檢查是否需要刷新。對於定時刷新這種使用第二種方式更好
