定时器使用_Timer

package com.lisn.signing.test;

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import com.lisn.signing.R;

import java.util.Timer;
import java.util.TimerTask;

public class test2Activity extends AppCompatActivity implements View.OnClickListener {

private long delay = 1000 * 3;

private int what = 88;
private int c;
Handler handler = new Handler() {

@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
if (msg.what == what) {
tv.setText("c=" + (c++));
}
}
};
private TextView tv;
private Button start;
private Button stop;
private Timer timer;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_test2);
initView();
}

private void initView() {
tv = (TextView) findViewById(R.id.tv);
start = (Button) findViewById(R.id.start);
stop = (Button) findViewById(R.id.stop);

start.setOnClickListener(this);
stop.setOnClickListener(this);
}

@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.start:
if (timer != null) {
timer.purge();
timer.cancel();
timer = null;
}
timer = new Timer();
timer.schedule(new MyTimerTask(), 0, delay);
break;
case R.id.stop:
if (timer != null) {
timer.purge();
timer.cancel();
}
break;
}
}

private class MyTimerTask extends TimerTask {
@Override
public void run() {
handler.sendEmptyMessage(what);
}
}

@Override
protected void onDestroy() {
super.onDestroy();
timer.purge();
timer.cancel();
}
}