自定义计时器

为了显示时间的流逝,下面我们来自定义一个TextView实现计时功能.代码如下:

import java.text.SimpleDateFormat;
import java.util.Date;

import android.content.Context;
import android.os.Handler;
import android.util.AttributeSet;
import android.view.View;
import android.widget.TextView;

public class TimerTextView extends TextView {
	private Handler handler = new Handler() {
		public void handleMessage(android.os.Message msg) {
			sendEmptyMessageDelayed(0, 1000);
			setTime();
			time += 1000;
		};
	};

	private long time;

	private SimpleDateFormat mformat = new SimpleDateFormat("mm:ss");

	public TimerTextView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		setTime();
	}

	public TimerTextView(Context context, AttributeSet attrs) {
		super(context, attrs);
		setTime();
	}

	public TimerTextView(Context context) {
		super(context);
		setTime();
	}
	//开始计时
	public void startTimer() {
		time = 1000;
		handler.sendEmptyMessageDelayed(0, 1000);
		setVisibility(View.VISIBLE);
	}
	//停止计时
	public void stopTimer() {
		time = 0;
		handler.removeMessages(0);
		setTime();
		setVisibility(View.GONE);
	}
	//更新时间
	private void setTime() {
		setText(mformat.format(new Date(time)));
	}
}