因为我的显示不出来,我修改了一下.

[aresjoy]

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.drawable.Drawable;
import android.support.v7.widget.AppCompatImageView;
import android.util.AttributeSet;
public class ScrollImageView extends AppCompatImageView {
 //需要设置为 scaltype = matrix

 public ScrollImageView(Context context) {
        super(context);
    }

    public ScrollImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public ScrollImageView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    /**
     加这个到addScrollListener
        if(contentListAdapter.getData().size()>0){
     int lastVisibleItemPosition = layoutManager.findLastVisibleItemPosition();
     for(int i=firstVisibleItemPosition;i<=lastVisibleItemPosition;i++){
     View view = layoutManager.findViewByPosition(i);
     ScrollImageView id_content_img = view.findViewById(R.id.id_content_img);
     if(id_content_img!=null){

     id_content_img.setDx(view.getTop(),layoutManager.getHeight());
     }

     }

     }
     */

    /**
      移动距离
     */
    private int mDx;

    // layout height ~0
    public void setDx(int viewTop, int layoutHeight){

        if(getDrawable() ==null){
            return;
        }

        int calculateHeight = getDrawable().getBounds().height() -viewHeight;
        if(calculateHeight<=0){
            //图片太小
            mDx =0;
            invalidate();
            return;
        }
        float rate = viewTop*1.0f/layoutHeight;
        mDx = (int) (calculateHeight*rate);
        invalidate();
    }

    private int viewHeight;

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        viewHeight = h;
    }

    @Override
    protected void onDraw(Canvas canvas) {
        Drawable drawable =getDrawable();
        if(drawable==null){
            super.onDraw(canvas);
            return;
        }
        //设置图片大小根据View的宽度
        int w = getWidth();
        int h = (int)(getWidth()*1.0f*drawable.getIntrinsicHeight()/drawable.getIntrinsicWidth());
        drawable.setBounds(0,0,w,h);
        canvas.save();
        canvas.translate(0,-mDx);
        super.onDraw(canvas);
        canvas.restore();
    }}