recycleview 的item图片倒影效果

public class ReflectItemView extends FrameLayout {    private static final String TAG = "ReflectItemView";    private Paint mRefPaint = null;    private Bitmap mReflectBitmap;    private Canvas mReflectCanvas;    private View mContentView;    private static final int REFHEIGHT = 100;    public ReflectItemView(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);        init(context, attrs);    }    public ReflectItemView(Context context, AttributeSet attrs) {        super(context, attrs);        init(context, attrs);    }    public ReflectItemView(Context context) {        super(context);        init(context, null);    }    private void init(Context context, AttributeSet attrs) {        if (attrs != null) {            TypedArray tArray = context.obtainStyledAttributes(attrs,                    R.styleable.ReflectItemView);// 获取配置属性            boolean isReflect = tArray.getBoolean(                    R.styleable.ReflectItemView_isReflect, false);            setReflection(isReflect);        }        //        if (mRefPaint == null) {            mRefPaint = new Paint(Paint.ANTI_ALIAS_FLAG);            // 倒影渐变.            mRefPaint                    .setShader(new LinearGradient(0, 0, 0, REFHEIGHT,                            0x70ffffff, 0x00ffffff, Shader.TileMode.MIRROR));            mRefPaint.setXfermode(new PorterDuffXfermode(                    PorterDuff.Mode.MULTIPLY));        }        setClipChildren(false);        setClipToPadding(false);    }    @Override    protected void onFinishInflate() {        super.onFinishInflate();        if (getChildCount() > 0) {            mContentView = getChildAt(0);        }    }    @Override    public void addView(View child) {        mContentView = child;        super.addView(child);    }    public View getContentView() {        return mContentView;    }// @Override// public boolean performClick() {//    if (mContentView != null) {//       return mContentView.performClick();//    } else {//       return super.performClick();//    }// }    private boolean mIsReflection = true;    public void setReflection(boolean ref) {        mIsReflection = ref;        invalidate();    }    public boolean isReflection() {        return this.mIsReflection;    }    @Override    protected void dispatchDraw(Canvas canvas) {        super.dispatchDraw(canvas);        if (mIsReflection) {            // 创建一个画布.            if (mReflectBitmap == null && mContentView != null) {                mReflectBitmap = Bitmap.createBitmap(mContentView.getWidth(),                        REFHEIGHT, Bitmap.Config.ARGB_8888);                mReflectCanvas = new Canvas(mReflectBitmap);            }            // 绘制倒影.            if (mContentView != null) {                drawReflection(mReflectCanvas);                canvas.save();                int dy = mContentView.getBottom() + getResources().getDimensionPixelOffset(R.dimen.size_8);                int dx = mContentView.getLeft();                canvas.translate(dx, dy);                canvas.drawBitmap(mReflectBitmap, 0, 0, null);                canvas.restore();            }        }    }    public Bitmap getReflectBitmap() {        return mReflectBitmap;    }    /**     * 绘制倒影.     */    public void drawReflection(Canvas canvas) {        canvas.save();        canvas.clipRect(0, 0, mContentView.getWidth(), REFHEIGHT);        canvas.save();        canvas.scale(1, -1);        canvas.translate(0, -mContentView.getHeight());        mContentView.draw(canvas);        canvas.restore();        canvas.drawRect(0, 0, mContentView.getWidth(), REFHEIGHT, mRefPaint);        canvas.restore();    }}

布局：
<com.aixuetang.future.view.ReflectItemView    android:layout_width="400px"    android:layout_height="610px"    android:background="@drawable/bg_item_recycle"    card:isReflect="true">    <com.aixuetang.future.view.RoundImageView        android:id="@+id/ivCourseImage"        android:layout_width="match_parent"        android:layout_height="match_parent"        android:scaleType="fitXY"        android:layout_marginBottom="20px"        card:type="round" /></com.aixuetang.future.view.ReflectItemView>
图片加载
Glide.with(itemView.getContext()).load(Constants.BASE_PIC_URL + model.getB_IMG()).asBitmap().error(R.drawable.ic_default_home)        .placeholder(R.drawable.ic_default_home).into(new SimpleTarget<Bitmap>() {    @Override    public void onResourceReady(Bitmap resource, GlideAnimation<? super Bitmap> glideAnimation) {        ivCourseImage.setImageBitmap(resource);    }    @Override    public void onLoadFailed(Exception e, Drawable errorDrawable) {    }});