记录下一个非常有用的小控件EditTextWithDel。就是在Android系统的输入框右边增加一个小图标。点击小图标能够清除输入框里面的内容，由于Android原生EditText不具备此功能，所以要想实现这一功能我们须要重写EditText。

效果图例如以下：

基本的思路就是为右边的图片设置监听。点击右边的图片清除输入框的内容并隐藏删除图标,由于我们不能直接给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,用输入框的的onTouchEvent()方法来模拟.

package com.xiaolijuan.edittextwithdeldome;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.util.Log;import android.view.MotionEvent;import android.widget.EditText;/** * @author: adan * @description: 自己定义带有删除功能的EditText * @projectName: EditTextWithDelDome * @date: 2016-02-28 * @time: 23:34 */public class EditTextWithDel extends EditText {
          private final static String TAG = "EditTextWithDel";    private Drawable imgInable;    private Drawable imgAble;    private Context mContext;    public EditTextWithDel(Context context) {        super(context);        mContext = context;        init();    }    public EditTextWithDel(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);        mContext = context;        init();    }    public EditTextWithDel(Context context, AttributeSet attrs) {        super(context, attrs);        mContext = context;        init();    }    private void init() {        imgAble = mContext.getResources().getDrawable(                R.mipmap.icon_delete_gray);        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();            }        });        setDrawable();    }    // 设置删除图片    private void setDrawable() {        if (length() < 1) {            setCompoundDrawablesWithIntrinsicBounds(null, null, null, null);        } else {            setCompoundDrawablesWithIntrinsicBounds(null, null, imgAble, null);        }    }    // 处理删除事件    @Override    public boolean onTouchEvent(MotionEvent event) {        if (imgAble != null && event.getAction() == MotionEvent.ACTION_UP) {            int eventX = (int) event.getRawX();            int eventY = (int) event.getRawY();            Log.e(TAG, "eventX = " + eventX + "; eventY = " + eventY);            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();    }}

setDrawable()方法，setCompoundDrawablesWithIntrinsicBounds(Drawable left, Drawable top, Drawable right, Drawable bottom)来在上、下、左、右设置图标，假设不想在某个地方显示，则设置为null。

接下来我们来使用它设置Activity的布局。一个我们自己定义的输入框，一个button

xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <RelativeLayout android:layout_width="match_parent" android:layout_height="60dp" android:layout_margin="25dp" android:background="#ffffff"> <ImageView android:id="@+id/img" android:layout_width="25dp" android:layout_height="30dp" android:layout_alignParentLeft="true" android:layout_centerVertical="true" android:layout_margin="5dp" android:src="@mipmap/ic_launcher" /> <ImageView android:layout_width="match_parent" android:layout_height="1dp" android:layout_alignParentBottom="true" android:layout_marginLeft="2dp" android:layout_marginRight="2dp" android:background="#56AB55" /> <com.xiaolijuan.edittextwithdeldome.EditTextWithDel android:id="@+id/et_phoneNumber" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentBottom="true" android:layout_alignParentRight="true" android:layout_alignParentTop="true" android:layout_margin="2dp" android:layout_toRightOf="@+id/img" android:background="#ffffff" android:hint="请输入手机号码" android:maxLength="11" android:phoneNumber="true" android:singleLine="true" /> </RelativeLayout> <Button android:id="@+id/btn" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_margin="25dp" android:background="#56AB55" android:text="确定" /> </LinearLayout>

然后就是界面代码的编写。主要測试下输入框

package com.xiaolijuan.edittextwithdeldome;import android.app.Activity;import android.os.Bundle;import android.text.TextUtils;import android.view.View;import android.widget.EditText;import android.widget.Toast;public class MainActivity extends Activity {
          private EditText userName;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        userName = (EditText) findViewById(R.id.et_phoneNumber);        findViewById(R.id.btn).setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                if (TextUtils.isEmpty(userName.getText().toString())){                    Toast.makeText(getApplicationContext(),"手机号码为空",Toast.LENGTH_LONG).show();                    return;                }                Toast.makeText(getApplicationContext(),userName.getText().toString(),Toast.LENGTH_LONG).show();            }        });    }}