public class HeadZoomScrollView extends NestedScrollView {

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

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

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

    //用于記錄下拉位置
    private float y = 0f;
    //zoomView原本的寬高
    private int zoomViewWidth = 0;
    private int zoomViewHeight = 0;

    //是否正在放大
    private boolean mScaling = false;

    //放大的view，默認(rèn)為第一個子view
    private View zoomView;

    public void setZoomView(View zoomView) {
        this.zoomView = zoomView;
    }

    //滑動放大系數(shù)，系數(shù)越大，滑動時放大程度越大
    private float mScaleRatio = 0.4f;

    public void setmScaleRatio(float mScaleRatio) {
        this.mScaleRatio = mScaleRatio;
    }

    //最大的放大倍數(shù)
    private float mScaleTimes = 2f;

    public void setmScaleTimes(int mScaleTimes) {
        this.mScaleTimes = mScaleTimes;
    }

    //回彈時間系數(shù)，系數(shù)越小，回彈越快
    private float mReplyRatio = 0.5f;

    public void setmReplyRatio(float mReplyRatio) {
        this.mReplyRatio = mReplyRatio;
    }

    //滾動觸發(fā)子view橫向放大的方法
    private float moveDistance = 300.0f;

    public void setMoveDistance(float moveDistance) {
        this.moveDistance = moveDistance;
    }

    //是否橫向拉伸，默認(rèn)為true
    private boolean isTransverse = true;

    public void setTransverse(boolean isTransverse) {
        this.isTransverse = isTransverse;
    }

    @Override
    protected void onFinishInflate() {
        super.onFinishInflate();
        //不可過度滾動，否則上移后下拉會出現(xiàn)部分空白的情況
        setOverScrollMode(OVER_SCROLL_NEVER);
        //獲得默認(rèn)第一個view
        if (getChildAt(0) != null && getChildAt(0) instanceof ViewGroup && zoomView == null) {
            ViewGroup vg = (ViewGroup) getChildAt(0);
            if (vg.getChildCount() > 0) {
                zoomView = vg.getChildAt(0);
            }
        }
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        if (zoomViewWidth <= 0 || zoomViewHeight <= 0) {
            zoomViewWidth = zoomView.getMeasuredWidth();
            zoomViewHeight = zoomView.getMeasuredHeight();
        }
        switch (ev.getAction()) {
            case MotionEvent.ACTION_UP:
                //手指離開后恢復(fù)圖片
                mScaling = false;
                replyImage();
                break;
            case MotionEvent.ACTION_MOVE:
                if (!mScaling) {
                    if (getScrollY() == 0) {
                        y = ev.getY();// 滾動到頂部時記錄位置，否則正常返回
                    } else {
                        break;
                    }
                }
                int distance = (int) ((ev.getY() - y) * mScaleRatio); // 滾動距離乘以一個系數(shù)
                if (distance < 0) { // 當(dāng)前位置比記錄位置要小，正常返回
                    break;
                }
                // 處理放大
                mScaling = true;
                setZoom(distance);
                return true; // 返回true表示已經(jīng)完成觸摸事件，不再處理
        }
        return super.onTouchEvent(ev);
    }

    //拉伸效果
    public void setZoom(float zoom) {
        if (zoomViewWidth <= 0 || zoomViewHeight <= 0) {
            return;
        }
        ViewGroup.LayoutParams lp = zoomView.getLayoutParams();
        if (isTransverse) {
            if (zoom <= moveDistance) {
                lp.width = (int) (zoomViewWidth);
            } else {
                lp.width = (int) (zoomViewWidth + zoom);
                if (onZoomListener != null) {
                    onZoomListener.onZoom(zoom);
                }
            }
        } else {
            lp.width = (int) (zoomViewWidth);
        }
        lp.height = (int) (zoomViewHeight * ((zoomViewWidth + zoom) / zoomViewWidth));
        ((MarginLayoutParams) lp).setMargins(-(lp.width - zoomViewWidth) / 2, 0, 0, 0);
        zoomView.setLayoutParams(lp);
    }

	private OnZoomListener onZoomListener;

    public interface OnZoomListener {
        void onZoom(float zoom);
    }

    public void setOnZoomListener(OnZoomListener onZoomListener){
        this.onZoomListener = onZoomListener;
    }

    //回彈動畫
    private void replyImage() {
        float distance = 0f;
        if(isTransverse){
            distance = zoomView.getMeasuredWidth() - zoomViewWidth;
        }else{
            distance = zoomView.getMeasuredHeight() - zoomViewHeight;
        }
        ValueAnimator valueAnimator = ValueAnimator.ofFloat(distance, 0f).setDuration((long) (distance * mReplyRatio));
        valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
            @Override
            public void onAnimationUpdate(ValueAnimator animation) {
                setZoom((Float) animation.getAnimatedValue());
            }
        });
        valueAnimator.start();
    }

}

<com.lwj.test.common.view.HeadZoomScrollView
        android:id="@+id/scroll_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">
        <ImageView
            android:id="@+id/iv_show"
            android:layout_width="match_parent"
            android:layout_height="200dp"
            android:layout_weight="1"
            android:src="@drawable/ic_my_background"/>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="60dp"
            android:text="數(shù)據(jù)1"/>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="60dp"
            android:text="數(shù)據(jù)2"/>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="60dp"
            android:text="數(shù)據(jù)3"/>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="60dp"
            android:text="數(shù)據(jù)4"/>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="60dp"
            android:text="數(shù)據(jù)5"/>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="60dp"
            android:text="數(shù)據(jù)6"/>
    </LinearLayout>
</com.lwj.test.common.view.HeadZoomScrollView>

setZoomView(View view); // 設(shè)置要放大的view，默認(rèn)為第一個子view
setmScaleRatio(float mScaleRatio); // 設(shè)置滑動放大系數(shù)，系數(shù)越大，滑動時，放大程度越大
setmScaleTimes(int mScaleTimes); // 設(shè)置最大的放大倍數(shù) 
setmReplyRatio(float mReplyRatio); //回彈時間系數(shù)，系數(shù)越小，回彈越快
setMoveDistance(float moveDistance); // 設(shè)置放大時移動的距離
setTransverse(boolean isTransverse); // 設(shè)置是否進(jìn)行橫向拉伸
setOnZoomListener(OnZoomListener onZoomListener);// 設(shè)置滑動距離監(jiān)聽