Android實戰教程 Chronometer實現倒計時

Android提供了實現按照秒計時的API，今天就是用這個API實現簡單的倒計時。

來個布局：

package com.example.timer;

import android.app.Activity;
import android.os.Bundle;
import android.os.SystemClock;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Chronometer;

public class MainActivity extends Activity {
	private Chronometer myChronometer = null;
	private Button btnStart = null;
	private Button btnStop = null;
	private Button btnBase = null;
	private Button btnFormat = null;

	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState); // 生命周期方法
		super.setContentView(R.layout.activity_main); // 設置要使用的布局管理器
		this.myChronometer = (Chronometer) super
				.findViewById(R.id.myChronometer);
		btnStart = (Button) super.findViewById(R.id.btnStart);
		btnStop = (Button) super.findViewById(R.id.btnStop);
		btnBase = (Button) super.findViewById(R.id.btnBase);
		btnFormat = (Button) super.findViewById(R.id.btnFormat);
		btnStart.setOnClickListener(new OnClickListenerStart());
		btnStop.setOnClickListener(new OnClickListenerStop());
		btnBase.setOnClickListener(new OnClickListenerBase());
		btnFormat.setOnClickListener(new OnClickListenerFormat());
	}

	private class OnClickListenerStart implements OnClickListener {

		public void onClick(View arg0) {
			myChronometer.start();

		}

	}

	private class OnClickListenerStop implements OnClickListener {

		public void onClick(View arg0) {
			myChronometer.stop();

		}

	}

	private class OnClickListenerBase implements OnClickListener {

		public void onClick(View arg0) {
			myChronometer.setBase(SystemClock.elapsedRealtime());

		}

	}

	private class OnClickListenerFormat implements OnClickListener {

		public void onClick(View arg0) {
			myChronometer.setFormat("新的顯示格式：%s。");

		}

	}

}