Android控件倒計時的實現

使用CountDownTimer實現比較簡單，以下是將Button對象傳進來的TimeCountButton類。

[java]
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 + "'）"); 
        } 
    } 
} 

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 + "'）");
  }
 }
}