17 create a timer ,need multi thread,which type?
the background thred need to use Handler to communicate to the UI thread
use Timer task and Handler task to buid a simple time
package pom.poly.com.simpletimer;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.widget.Button;
import android.widget.TextView;
import java.util.Timer;
import java.util.TimerTask;
import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
public class MainActivity extends AppCompatActivity {
@BindView(R.id.tvTime)
TextView tvTime;
@BindView(R.id.btStart)
Button btStart;
private Timer timer;
private Handler mHandler;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.bind(this);
tvTime = (TextView) findViewById(R.id.tvTime);
mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
if (msg.what == 1) {
tvTime.setText(msg.arg1 + "");
}
}
};
}
@Override
protected void onPause() {
super.onPause();
timer.cancel();
}
@OnClick(R.id.btStart)
public void onClick() {
timer = new Timer(true);
timer.schedule(new MyTimerTask(), 0, 1000);
}
private class MyTimerTask extends TimerTask {
private int second = 0;
@Override
public void run() {
second++;
Log.d("second", second + "");
Message message = new Message();
message.what = 1;
message.arg1 = second;
mHandler.sendMessage(message);
}
}
}
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however,it can’t not pause and restart
so,Timer is not a good way to create a task to Create a Background Thread task
example
make by sharepreference,Timer task.
