Android 设置DrawableRight和DrawableLeft点击事件

Android的TextView有个DrawableLeft和DrawableRight属性，UI布局中经常会用到。比如登陆界面，用户名和密码前面的图像，就是用DrawableLeft来设置的。

但比较郁闷的是，android并没有为DrawableLeft和DrawableRight提供监听点击事件的api，但这个需求是很常见的，比如输入密码的时候，点击右边的眼睛，密码变为明文。

其实思路很简单，我们只要重写EditText的onTouchEvent，捕捉到点击事件，然后判断用户点击的位置是否点击到图标即可，不废话，用代码说话。

1、添加XTextView类继承自TextView

import android.content.Context;import android.graphics.drawable.Drawable;import android.util.AttributeSet;import android.view.MotionEvent;import android.view.View;public class XTextView extends android.support.v7.widget.AppCompatTextView {    private DrawableLeftListener mLeftListener;    private DrawableRightListener mRightListener;    final int DRAWABLE_LEFT = 0;    final int DRAWABLE_TOP = 1;    final int DRAWABLE_RIGHT = 2;    final int DRAWABLE_BOTTOM = 3;    public XTextView(Context context) {        super(context);    }    public XTextView(Context context, AttributeSet attrs) {        super(context, attrs);    }    public XTextView(Context context, AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);    }    public void setDrawableLeftListener(DrawableLeftListener listener) {        this.mLeftListener = listener;    }    public void setDrawableRightListener(DrawableRightListener listener) {        this.mRightListener = listener;    }    public interface DrawableLeftListener {        public void onDrawableLeftClick(View view);    }    public interface DrawableRightListener {        public void onDrawableRightClick(View view);    }    @Override    public boolean onTouchEvent(MotionEvent event) {        switch (event.getAction()) {            case MotionEvent.ACTION_DOWN:                if (mRightListener != null) {                    Drawable drawableRight = getCompoundDrawables()[DRAWABLE_RIGHT];                    if (drawableRight != null && event.getRawX() >= (getRight() - drawableRight.getBounds().width())) {                        mRightListener.onDrawableRightClick(this);                        return true;                    }                }                if (mLeftListener != null) {                    Drawable drawableLeft = getCompoundDrawables()[DRAWABLE_LEFT];                    if (drawableLeft != null && event.getRawX() <= (getLeft() + drawableLeft.getBounds().width()))                        mLeftListener.onDrawableLeftClick(this);                    return true;                }                break;        }        return super.onTouchEvent(event);    }}

2、layout

<LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="vertical">        <com.term.paimai.helper.XTextView            android:id="@+id/login_back"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:layout_margin="@dimen/margin_normal"            android:drawableLeft="@mipmap/ic_tab_triangle_left"            android:text="@string/login"            android:textAlignment="center"            android:textSize="@dimen/text_size_large"/>

3、activity添加点击响应

xtvLoginBack.setDrawableLeftListener(new XTextView.DrawableLeftListener() {    @Override    public void onDrawableLeftClick(View view) {        onBackPressed();    }});

参考：

http://blog.csdn.net/tom_xiaoxie/article/details/50771763