Android控件倒计时的实现

使用CountDownTimer实现比较简单，以下是将Button对象传进来的TimeCountButton类。

public class CountDownButton extends CountDownTimer {
	public static final int TIME_COUNT_FUTURE = 60000;
	public static final int TIME_COUNT_INTERVAL = 1000;
	
	private Context mContext;
	private Button mButton;
	private String mOriginalText;
	private Drawable mOriginalBackground;
	private Drawable mTickBackground;
	private int mOriginalTextColor;
	
	public CountDownButton() {
		super(TIME_COUNT_FUTURE, TIME_COUNT_INTERVAL);
	}
	
	public CountDownButton(long millisInFuture, long countDownInterval) {
		super(millisInFuture, countDownInterval);
	}
	
	public void init(Context context, Button button) {
		this.mContext = context;
		this.mButton = button;
		this.mOriginalText = mButton.getText().toString();
		this.mOriginalBackground = mButton.getBackground();
		this.mTickBackground = this.mOriginalBackground;
		this.mOriginalTextColor = mButton.getCurrentTextColor();
	}
	
	public void setTickDrawable(Drawable tickDrawable) {
		this.mTickBackground = tickDrawable;
	}

	@Override
	public void onFinish() {
		if (mContext != null && mButton != null) {
			mButton.setText(mOriginalText);
			mButton.setTextColor(mOriginalTextColor);
			mButton.setBackgroundDrawable(mOriginalBackground);
			mButton.setClickable(true);
		}
	}

	@Override
	public void onTick(long millisUntilFinished) {
		if (mContext != null && mButton != null) {
			mButton.setClickable(false);
			mButton.setBackgroundDrawable(mTickBackground);
			mButton.setTextColor(mContext.getResources().getColor(android.R.color.darker_gray));
			mButton.setText(mOriginalText + "（" + millisUntilFinished / 1000 + "'）");
		}
	}
}