参考文章:
Android实现计时与倒计时的几种方法
Timer和TimerTask的简单介绍
方法二:TimerTask与Handler(不用Timer的改进型)
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<TextView
android:id="@+id/txtView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:text="倒计时:"
android:textSize="30dp" />
<TextView
android:id="@+id/txtView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_toLeftOf="@id/txtView1"
android:text="5"
android:textSize="30dp"/>
</RelativeLayout>
public class PrepareActivity extends AppCompatActivity{
private int recLen = 5;
Timer timer = new Timer();
private TextView txtView;
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_prepare);
txtView =findViewById(R.id.txtView);
prepare();
}
private Handler handler = new Handler(Looper.myLooper()){
@Override
public void handleMessage(@NonNull Message msg){
switch(msg.what){
case 1:
txtView.setText(""+recLen);
if (--recLen<0){
timer.cancel();
Intent intent = new Intent(getApplicationContext(),MainActivity.class);
startActivity(intent);
finish();
}
}
}
};
public void prepare(){
TimerTask task = new TimerTask() {
@Override
public void run() {
recLen--;
Message message = new Message();
message.what = 1;
handler.sendEmptyMessage(1);
}
};
timer.schedule(task,1000,1000);
}
}
<!-- 将广告页面注册为程序首页 -->
<activity
android:name=".PrepareActivity"
android:label="@string/title_activity_prepare"
android:theme="@style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter></activity>
<activity android:name=".MainActivity">
</activity>