timer實現倒計時
阿新 • • 發佈:2019-01-02
package com.bwei.timer; 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.view.Menu; import android.widget.TextView; import android.widget.Toast; public class MainActivity extends Activity { int time=3; //建立Timer計時器 Timer timer = new Timer(); private TextView tv_time; private Handler handler = new Handler(){ public void handleMessage(android.os.Message msg) { if(msg.what==0){ if(time==-1){ Toast.makeText(MainActivity.this, "倒計時結束", 0).show(); return; } tv_time.setText("倒計時:"+(time--)+"秒"); } }; }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); tv_time = (TextView) findViewById(R.id.tv_time); //執行計時任務 timer.schedule(new MyTimerTask(), 1000, 1000); } //定義TimerTask private class MyTimerTask extends TimerTask{ Message message = handler.obtainMessage(0); message.sendToTarget(); } } }