Android -- 倒计时Button的实现

1、自定义Button类

public class CountDownButton extends android.support.v7.widget.AppCompatButton implements View.OnClickListener {

    private Context mContext;
    private OnClickListener mOnClickListener;
    private Timer mTimer;//调度器
    private TimerTask mTask;
    private int temp_duration;
    private int countDownTime = 60000;//默认需要倒计时的时间毫秒数
    private String countDownText;//倒计时之后的文字显示
    private String countDowningFormat ;//正在倒计时时要显示的格式

    public CountDownButton(Context context) {
        super(context);
        init(context, null);

    }

    public CountDownButton(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context, attrs);
    }

    private Handler mHandler = new Handler(){
        @Override
        public void handleMessage(Message msg) {
            String text = String.format(countDowningFormat, temp_duration / 1000);
            CountDownButton.this.setText(text);
            temp_duration -= 1000;
            if (temp_duration < 0) { //倒计时结束
                CountDownButton.this.setEnabled(true);
                CountDownButton.this.setText(countDownText);
                stopTimer();
            }
        }
    };

    private void init(Context context, AttributeSet attrs) {
        this.mContext = context;
        countDowningFormat = "重新获取(%d)";
        countDownText = "重新获取";
        if(null != attrs){
            TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.CountDown);
            countDownTime = array.getInt(R.styleable.CountDown_countDownTime, 0);
            countDownText = array.getString(R.styleable.CountDown_countDownText);
            if(!TextUtils.isEmpty(array.getString(R.styleable.CountDown_countDowningFormat))){
                countDowningFormat = array.getString(R.styleable.CountDown_countDowningFormat);
            }
            array.recycle();
        }
        setOnClickListener(this);
    }

    @Override
    public void setOnClickListener(OnClickListener onClickListener) {//提供外部访问方法
        if (onClickListener instanceof CountDownButton) {
            super.setOnClickListener(onClickListener);
        } else {
            this.mOnClickListener = onClickListener;
        }
    }

    @Override
    public void onClick(View view) {
        if (mOnClickListener != null) {
            mOnClickListener.onClick(view);
        }
        startTimer();
    }

    //计时开始
    private void startTimer(){
        temp_duration = countDownTime;
        CountDownButton.this.setEnabled(false);
        mTimer = new Timer();
        mTask = new TimerTask() {
            @Override
            public void run() {
                mHandler.sendEmptyMessage(0x01);
            }
        };
        mTimer.schedule(mTask, 0, 1000);//调度分配，延迟0秒，时间间隔为1秒
    }

    //计时结束
    private void stopTimer(){
        if (mTask != null) {
            mTask.cancel();
            mTask = null;
        }
        if (mTimer != null) {
            mTimer.cancel();
            mTimer = null;
        }
    }
}

2、Layout使用

3、values attrs.xml文件中自定义属性

参考：

https://www.oschina.net/code/snippet_1187615_49484

http://blog.csdn.net/chengxu_hou/article/details/54972502