public class ClearEditText extends EditText implements OnFocusChangeListener, TextWatcher {/*** 删除按钮的引用*/private Drawable mClearDrawable;/*** 控件是否有焦点*/private boolean hasFoucs;public ClearEditText(Context context) {this(context, null);}public ClearEditText(Context context, AttributeSet attrs) {// 这里构造方法也很重要，不加这个很多属性不能再XML里面定义this(context, attrs, android.R.attr.editTextStyle);}public ClearEditText(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);init();}private void init() {// 获取EditText的DrawableRight,假如没有设置我们就使用默认的图片mClearDrawable = getCompoundDrawables()[2];if (mClearDrawable == null) {// throw new// NullPointerException("You can add drawableRight attribute in XML");mClearDrawable = getResources().getDrawable(R.drawable.ic_close_circle);}mClearDrawable.setBounds(0, 0, mClearDrawable.getIntrinsicWidth(), mClearDrawable.getIntrinsicHeight());// 默认设置隐藏图标setClearIconVisible(false);// 设置焦点改变的监听setOnFocusChangeListener(this);// 设置输入框里面内容发生改变的监听addTextChangedListener(this);}/*** 因为我们不能直接给EditText设置点击事件，所以我们用记住我们按下的位置来模拟点击事件 当我们按下的位置 在 EditText的宽度 -* 图标到控件右边的间距 - 图标的宽度 和 EditText的宽度 - 图标到控件右边的间距之间我们就算点击了图标，竖直方向就没有考虑*/@Overridepublic 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);}/*** 当ClearEditText焦点发生变化的时候，判断里面字符串长度设置清除图标的显示与隐藏*/@Overridepublic void onFocusChange(View v, boolean hasFocus) {this.hasFoucs = hasFocus;if (hasFocus) {setClearIconVisible(getText().length() > 0);} else {setClearIconVisible(false);}}/*** 设置清除图标的显示与隐藏，调用setCompoundDrawables为EditText绘制上去* * @param visible*/protected void setClearIconVisible(boolean visible) {Drawable right = visible ? mClearDrawable : null;setCompoundDrawables(getCompoundDrawables()[0], getCompoundDrawables()[1], right, getCompoundDrawables()[3]);}/*** 当输入框里面内容发生变化的时候回调的方法*/@Overridepublic void onTextChanged(CharSequence s, int start, int count, int after) {if (hasFoucs) {setClearIconVisible(s.length() > 0);}}@Overridepublic void beforeTextChanged(CharSequence s, int start, int count, int after) {}@Overridepublic void afterTextChanged(Editable s) {}}