Android ClearEditText：输入用户名、密码错误时整体删除及输入为空时候晃动提示

package com.lixu.clearedittext;


import android.app.Activity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends Activity {
    private Toast mToast;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        final ClearEditText username = (ClearEditText) findViewById(R.id.username);
        final ClearEditText password = (ClearEditText) findViewById(R.id.password);
        
        ((Button) findViewById(R.id.login)).setOnClickListener(new OnClickListener() {
            
            @Override
            public void onClick(View v) {
                if(TextUtils.isEmpty(username.getText())){
                    //设置晃动
                    username.setShakeAnimation();
                    //设置提示
                    showToast("用户名不能为空");
                    return;
                }
                
                if(TextUtils.isEmpty(password.getText())){
                    password.setShakeAnimation();
                    showToast("密码不能为空");
                    return;
                }
            }
        });
    }
    
    /**
     * 显示Toast消息
     * @param msg
     */
    private void showToast(String msg){
        if(mToast == null){
            mToast = Toast.makeText(this, msg, Toast.LENGTH_SHORT);
        }else{
            mToast.setText(msg);
        }
        mToast.show();
    }


}

package com.lixu.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 { 
    /**
     * 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,右边位置图片
        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
     */
    @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);
    }
 
    /**
     * 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
     */
    @Override 
    public 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
     */
    @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) { 
         
    } 
    
   
    /**
     * 设置晃动动画
     */
    public void setShakeAnimation(){
        this.setAnimation(shakeAnimation(5));
    }
    
    
    /**
     * 晃动动画
     * @param counts 1秒钟晃动多少下
     * @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;
    }
 
 
}

xml文件：

 1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:background="#95CAE4">
 6 
 7 
 8     <com.lixu.clearedittext.ClearEditText
 9         android:id="@+id/username"
10         android:layout_marginTop="60dp"
11         android:layout_width="fill_parent"
12         android:background="@drawable/login_edittext_bg" 
13         android:drawableLeft="@drawable/icon_user"
14         android:layout_marginLeft="10dip"
15         android:layout_marginRight="10dip"
16         android:singleLine="true"
17         android:drawableRight="@drawable/delete_selector"
18         android:hint="输入用户名"
19         android:layout_height="wrap_content" >
20 
21     </com.lixu.clearedittext.ClearEditText>
22 
23     <com.lixu.clearedittext.ClearEditText
24         android:id="@+id/password"
25         android:layout_marginLeft="10dip"
26         android:layout_marginRight="10dip"
27         android:layout_marginTop="10dip"
28         android:drawableLeft="@drawable/account_icon"
29         android:hint="输入密码"
30         android:singleLine="true"
31         android:password="true"
32         android:drawableRight="@drawable/delete_selector"
33         android:layout_width="fill_parent"
34         android:layout_height="wrap_content"
35         android:layout_below="@id/username"
36         android:background="@drawable/login_edittext_bg" >
37     </com.lixu.clearedittext.ClearEditText>
38 
39     <Button
40         android:id="@+id/login"
41         android:layout_width="fill_parent"
42         android:layout_height="wrap_content"
43         android:layout_marginLeft="10dip"
44         android:layout_marginRight="10dip"
45         android:background="@drawable/login_button_bg"
46         android:textSize="18sp"
47         android:textColor="@android:color/white"
48         android:layout_below="@+id/password"
49         android:layout_marginTop="25dp"
50         android:text="登录" />
51 
52 </RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<selector
  xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true" android:drawable="@drawable/search_clear_pressed" />
    <item android:drawable="@drawable/search_clear_normal" />
</selector>

<?xml version="1.0" encoding="UTF-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:drawable="@drawable/btn_style_one_pressed" android:state_pressed="true"></item>
    <item android:drawable="@drawable/btn_style_one_focused" android:state_focused="true"></item>
    <item android:drawable="@drawable/btn_style_one_normal"></item>

</selector>

<?xml version="1.0" encoding="UTF-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_focused="true" android:drawable="@drawable/login_edit_pressed"></item>
    <item android:state_pressed="true" android:drawable="@drawable/login_edit_pressed"></item>
    <item android:drawable="@drawable/login_edit_normal"></item>
</selector>

运行效果图：