带删除的EditText

　　在安卓开发中EditText是比较常用的控件之一，那我们平常看到EditText填写了内容之后右边会出现一个删除的按钮，这样可以方便用户对其中文本清空操作，是非常人性化的，我们可以重写EditText来达到这样的效果。代码很简单，需要的盆友直接考皮就可以用，注意里面引用到一个删除按钮的图片资源。

package com.android.app;

import android.content.Context;
import android.graphics.Rect;
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 com.android.app.R;

public class EditText extends android.widget.EditText implements View.OnFocusChangeListener {

    private Drawable mDeleteIcon;
    private Context mContext;

    public EditText(Context context) {
        super(context);
        mContext = context;
        init();
    }

    public EditText(Context context, AttributeSet attrs) {
        super(context, attrs);
        mContext = context;
        init();
    }

    public EditText(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        mContext = context;
        init();
    }

    private void init() {
        this.setOnFocusChangeListener(this);
        mDeleteIcon = mContext.getResources().getDrawable(R.drawable.ic_input_close);
        if (this.length() > 0) {
            setCompoundDrawablesWithIntrinsicBounds(null, null, mDeleteIcon, null);
        }
        this.addTextChangedListener(new TextWatcher() {

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            }

            @Override
            public void afterTextChanged(Editable s) {
                setDrawable();
            }
        });
    }

    // 设置删除图片
    private void setDrawable() {
        if (this.length() > 0)
            setCompoundDrawablesWithIntrinsicBounds(null, null, mDeleteIcon, null);
        else
            setCompoundDrawablesWithIntrinsicBounds(null, null, null, null);
    }

    @Override
    public void onFocusChange(View view, boolean b) {
        if (!b)
            setCompoundDrawablesWithIntrinsicBounds(null, null, null, null);
        else
            setDrawable();
    }

    // 处理删除事件
    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (mDeleteIcon != null && event.getAction() == MotionEvent.ACTION_UP) {
            int eventX = (int) event.getRawX();
            int eventY = (int) event.getRawY();
            Rect rect = new Rect();
            getGlobalVisibleRect(rect);
            rect.left = rect.right - 50;
            if (rect.contains(eventX, eventY))
                setText("");
        }
        return super.onTouchEvent(event);
    }

    @Override
    protected void finalize() throws Throwable {
        super.finalize();
    }
}