package com.example.clearedittext;  import android.content.Context; import android.graphics.drawable.Drawable; import android.text.Editable; import android.text.TextWatcher; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.View; import android.view.View.OnFocusChangeListener; import android.view.animation.Animation; import android.view.animation.CycleInterpolator; import android.view.animation.TranslateAnimation; import android.widget.EditText;  public class ClearEditText extends EditText implements      OnFocusChangeListener, TextWatcher {    /**    * 刪除按鈕的引用    */   private Drawable mClearDrawable;    /**    * 控件是否有焦點    */   private boolean hasFoucs;     public ClearEditText(Context context) {      this(context, null);    }      public ClearEditText(Context context, AttributeSet attrs) {      //這里構造方法也很重要，不加這個很多屬性不能再XML里面定義     this(context, attrs, android.R.attr.editTextStyle);    }       public ClearEditText(Context context, AttributeSet attrs, int defStyle) {     super(context, attrs, defStyle);     init();   }         private void init() {      //獲取EditText的DrawableRight,假如沒有設置我們就使用默認的圖片     mClearDrawable = getCompoundDrawables()[2];      if (mClearDrawable == null) {  //     throw new NullPointerException("You can add drawableRight attribute in XML");       mClearDrawable = getResources().getDrawable(R.drawable.delete_selector);      }           mClearDrawable.setBounds(0, 0, mClearDrawable.getIntrinsicWidth(), mClearDrawable.getIntrinsicHeight());      //默認設置隱藏圖標     setClearIconVisible(false);      //設置焦點改變的監聽     setOnFocusChangeListener(this);      //設置輸入框里面內容發生改變的監聽     addTextChangedListener(this);    }        /**    * 因為我們不能直接給EditText設置點擊事件，所以我們用記住我們按下的位置來模擬點擊事件    * 當我們按下的位置 在 EditText的寬度 - 圖標到控件右邊的間距 - 圖標的寬度 和    * EditText的寬度 - 圖標到控件右邊的間距之間我們就算點擊了圖標，豎直方向就沒有考慮    */   @Override    public boolean onTouchEvent(MotionEvent event) {     if (event.getAction() == MotionEvent.ACTION_UP) {       if (getCompoundDrawables()[2] != null) {          boolean touchable = event.getX() > (getWidth() - getTotalPaddingRight())             && (event.getX() < ((getWidth() - getPaddingRight())));                  if (touchable) {           this.setText("");         }       }     }      return super.onTouchEvent(event);   }     /**    * 當ClearEditText焦點發生變化的時候，判斷里面字符串長度設置清除圖標的顯示與隱藏    */   @Override    public void onFocusChange(View v, boolean hasFocus) {      this.hasFoucs = hasFocus;     if (hasFocus) {        setClearIconVisible(getText().length() > 0);      } else {        setClearIconVisible(false);      }    }        /**    * 設置清除圖標的顯示與隱藏，調用setCompoundDrawables為EditText繪制上去    * @param visible    */   protected void setClearIconVisible(boolean visible) {      Drawable right = visible ? mClearDrawable : null;      setCompoundDrawables(getCompoundDrawables()[0],          getCompoundDrawables()[1], right, getCompoundDrawables()[3]);    }           /**    * 當輸入框里面內容發生變化的時候回調的方法    */   @Override    public void onTextChanged(CharSequence s, int start, int count,        int after) {          if(hasFoucs){           setClearIconVisible(s.length() > 0);         }   }      @Override    public void beforeTextChanged(CharSequence s, int start, int count,        int after) {          }      @Override    public void afterTextChanged(Editable s) {          }          /**    * 設置晃動動畫    */   public void setShakeAnimation(){     this.setAnimation(shakeAnimation(5));   }         /**    * 晃動動畫    * @param counts 1秒鐘晃動多少下    * @return    */   public static Animation shakeAnimation(int counts){     Animation translateAnimation = new TranslateAnimation(0, 10, 0, 0);     translateAnimation.setInterpolator(new CycleInterpolator(counts));     translateAnimation.setDuration(1000);     return translateAnimation;   }     }