android - CollapsingToolbarLayout 滚动 Bug - 有时向上滚动会卡住

Question

我正在我的 Android 应用程序中创建滚动 Activity 。 Activity 有一个具有视差效果的 CollapsingToolbarLayout。

当我向上滚动 appbarlayout 下面的布局时，它会平滑地向上滚动，appbarlayout 将折叠到标题。ImageView 和 TextView 将向上滚动到标题。当我向下滚动布局时，它们都会回到开头。

错误在这里:

当我在某些设备上运行 Activity 时，有时当我向上滚动时，布局会在此处上下停留几秒钟，然后返回顶部。当我在其他一些设备上运行该 Activity 时，一切正常，没有发生任何错误。

此错误的演示:https://share.weiyun.com/1d797a4a92580e1595eacb226f9a92a3

这是布局:

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="nczz.cn.helloworld.ScrollingActivity"
    >
    <android.support.design.widget.AppBarLayout
        android:id="@+id/app_bar"
        android:layout_width="match_parent"
        android:layout_height="@dimen/app_bar_height"
        android:background="#FA7199"
        app:layout_scrollFlags="scroll|enterAlways"
        android:theme="@style/AppTheme.AppBarOverlay">

        <nczz.cn.widget.CollapsingImageTextLayout
            android:id="@+id/imageTextLayout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_scrollFlags="scroll|exitUntilCollapsed"
            app:title_id="@+id/test_title"
            app:text_id="@+id/test_text"
            app:img_scale="0.6"
            app:text_scale="0.6"
            app:text_margin_left="110dp"
            app:img_id="@+id/test_img"
            app:img_margin_left="55dp"
            >
            <LinearLayout
                android:id="@+id/test_title"
                android:layout_width="match_parent"
                android:layout_height="80dp"
                android:background="#FA7199"
                android:gravity="center_vertical"
                android:orientation="horizontal"
                >
                <ImageView
                    android:id="@+id/return_btn"
                    android:layout_width="15dp"
                    android:layout_height="15dp"
                    android:layout_marginLeft="20dp"
                    android:layout_centerVertical="true"
                    android:src="@drawable/left" />
            </LinearLayout>

            <ImageView
                android:id="@+id/test_img"
                android:layout_width="80dp"
                android:layout_height="80dp"
                android:scaleType="fitXY"
                android:src="@mipmap/ic_launcher"
                android:layout_centerInParent="true"
                android:layout_marginBottom="30dp"
                />

            <TextView
                android:id="@+id/test_text"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@+id/test_img"
                android:text="MoveText"
                android:textSize="20sp"
                android:textColor="@android:color/white"
                android:layout_marginTop="-20dp"
                android:layout_marginLeft="50dp"
                android:layout_centerInParent="true"
                />

        </nczz.cn.widget.CollapsingImageTextLayout>

    </android.support.design.widget.AppBarLayout>
    <include
        android:id="@+id/includelayout"
        layout="@layout/content_scrolling"/>

</android.support.design.widget.CoordinatorLayout>

这是 CollapsingImageTextLayout:

package nczz.cn.widget;

import android.content.Context;
import android.content.res.TypedArray;
import android.support.annotation.NonNull;
import android.support.design.widget.AppBarLayout;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;
import android.widget.RelativeLayout;

import nczz.cn.helloworld.R;


/**
 * Created by yahui.hu on 2017/4/21.
 */

public class CollapsingImageTextLayout extends RelativeLayout {

    private AppBarLayout.OnOffsetChangedListener mOffsetChangedListener;

    private int mTitleId, mTextId, mImageId;
    private int mTitleMarginLeft, mTitleMarginTop, mImgMarginLeft, mImgMarginTop;
    private float mTextScale, mImgScale;
    private View mTitle, mImg, mText;
    private boolean isGetView = true;
    private int mTitleHeight = 0;


    public CollapsingImageTextLayout(Context context) {
        this(context, null);
    }

    public CollapsingImageTextLayout(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public CollapsingImageTextLayout(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        TypedArray a = context.obtainStyledAttributes(attrs,
                R.styleable.CollapsingImageLayout, defStyleAttr, 0);
        mTitleId = a.getResourceId(R.styleable.CollapsingImageLayout_title_id, 0);
        mTextId = a.getResourceId(R.styleable.CollapsingImageLayout_text_id, 0);
        mImageId = a.getResourceId(R.styleable.CollapsingImageLayout_img_id, 0);
        mTextScale = a.getFloat(R.styleable.CollapsingImageLayout_text_scale, 0.4f);
        mImgScale = a.getFloat(R.styleable.CollapsingImageLayout_img_scale, 0.4f);
        mTitleMarginLeft = a.getDimensionPixelSize(R.styleable.CollapsingImageLayout_text_margin_left, 0);
        mTitleMarginTop = a.getDimensionPixelSize(R.styleable.CollapsingImageLayout_text_margin_top, 0);
        mImgMarginLeft = a.getDimensionPixelSize(R.styleable.CollapsingImageLayout_img_margin_left, 0);
        mImgMarginTop = a.getDimensionPixelSize(R.styleable.CollapsingImageLayout_img_margin_top, 0);
        a.recycle();

    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        getView();
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }

    private void getView() {
        if (!isGetView) {
            return;
        }
        if (mTitleId != 0) {
            mTitle = findViewById(mTitleId);
        }

        if (mTextId != 0) {
            mText = findViewById(mTextId);
        }

        if (mImageId != 0) {
            mImg = findViewById(mImageId);
        }
        isGetView = false;
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        super.onLayout(changed, l, t, r, b);

        if (mTitle != null) {
            getViewOffsetHelper(mTitle).onViewLayout(0, 0);
            setMinimumHeight(getHeightWithMargins(mTitle));
            mTitleHeight = mTitle.getHeight();
            this.bringChildToFront(mTitle);
        }

        if (mImg != null) {
            getViewOffsetHelper(mImg).onViewLayout(mImgMarginLeft, mImgMarginTop);
            this.bringChildToFront(mImg);
        }

        if (mText != null) {
            getViewOffsetHelper(mText).onViewLayout(mTitleMarginLeft, mTitleMarginTop);
            this.bringChildToFront(mText);
        }
    }

    static ViewHelper getViewOffsetHelper(View view) {
        ViewHelper offsetHelper = (ViewHelper) view.getTag(R.id.view_helper);
        if (offsetHelper == null) {
            offsetHelper = new ViewHelper(view);
            view.setTag(R.id.view_helper, offsetHelper);
        }
        return offsetHelper;
    }


    private static int getHeightWithMargins(@NonNull final View view) {
        final ViewGroup.LayoutParams lp = view.getLayoutParams();
        if (lp instanceof MarginLayoutParams) {
            final MarginLayoutParams mlp = (MarginLayoutParams) lp;
            return view.getHeight() + mlp.topMargin + mlp.bottomMargin;
        }
        return view.getHeight();
    }

    @Override
    protected void onAttachedToWindow() {
        super.onAttachedToWindow();
        ViewParent viewParent = getParent();
        if (viewParent instanceof AppBarLayout) {
            if (mOffsetChangedListener == null) mOffsetChangedListener = new OffsetListenerImp();
            ((AppBarLayout) viewParent).addOnOffsetChangedListener(mOffsetChangedListener);
        }
    }

    @Override
    protected void onDetachedFromWindow() {
        ViewParent viewParent = getParent();
        if (viewParent instanceof AppBarLayout) {
            ((AppBarLayout) viewParent).removeOnOffsetChangedListener(mOffsetChangedListener);
        }
        super.onDetachedFromWindow();
    }


    final int getMaxOffsetForPinChild(View child) {
        final ViewHelper offsetHelper = getViewOffsetHelper(child);
        final LayoutParams lp = (LayoutParams) child.getLayoutParams();
        return getHeight()
                - offsetHelper.getLayoutTop()
                - child.getHeight()
                - lp.bottomMargin;
    }

    static int constrain(int amount, int low, int high) {
        return amount < low ? low : (amount > high ? high : amount);
    }

    static int constrain(int amount, int low) {
        return amount < low ? low : amount;
    }

    private void setTopAndBottomOffset(View child, int verticalOffset) {
        ViewHelper viewHelper = (ViewHelper) child.getTag(R.id.view_helper);
        viewHelper.setTopAndBottomOffset(
                constrain(-verticalOffset, 0, getMaxOffsetForPinChild(child)));
        Log.e("setTopAndBottomOffset",""+-verticalOffset);
    }

    private void setTopAndBottomOffset(View child, int verticalOffset, float scale) {
        ViewHelper viewHelper = (ViewHelper) child.getTag(R.id.view_helper);
        viewHelper.setTopAndBottomOffset(
                constrain(-verticalOffset - getMaxOffset(viewHelper, scale),
                        0));
        //Log.e("setTopAndBottomOffset",""+-verticalOffset);
    }

    private void setLeftAndRightOffset(View child, int verticalOffset, float scale) {
        ViewHelper viewHelper = (ViewHelper) child.getTag(R.id.view_helper);
        int maxOffsetDistance = getMaxOffset(viewHelper, scale);
        int maxLeft = viewHelper.getLayoutLeft()
                + (viewHelper.getViewWidth() - viewHelper.getScaleViewWidth(scale))
                - viewHelper.getMarginTitleLeft();
        int realOffset = (int) (maxLeft * 1.0f / (maxOffsetDistance * 1.0f) * verticalOffset);
        realOffset = constrain(realOffset, -maxLeft, maxLeft);
        viewHelper.setLeftAndRightOffset(realOffset);
       // Log.e("setLeftAndRightOffset",""+realOffset);
    }

    private void setViewScale(View child, int verticalOffset, float scale) {
        ViewHelper viewHelper = (ViewHelper) child.getTag(R.id.view_helper);
        int maxOffsetDistance = getMaxOffset(viewHelper, scale);
        float realScale = -verticalOffset - maxOffsetDistance > 0 ? scale : verticalOffset == 0 ? 1f : 0f;
        if (realScale == 0) {
            realScale = (maxOffsetDistance + verticalOffset * (1 - scale)) / (maxOffsetDistance * 1f);
        }
        viewHelper.setViewOffsetScale(realScale);
    }

    private int getMaxOffset(ViewHelper viewHelper, float scale) {
        int scaleViewHeight = (int) (scale * viewHelper.getViewHeight());
        int offsetTitleDistance = scaleViewHeight >= mTitleHeight ? 0 : (mTitleHeight - scaleViewHeight) / 2;
        int marginTop = viewHelper.getMarginTitleTop() >= offsetTitleDistance ? offsetTitleDistance : viewHelper.getMarginTitleTop();
        return viewHelper.getLayoutBottom() - viewHelper.getScaleViewHeight(scale) - offsetTitleDistance - marginTop;
    }

    private class OffsetListenerImp implements AppBarLayout.OnOffsetChangedListener {
        @Override
        public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
            if (mTitle != null) {
                setTopAndBottomOffset(mTitle, verticalOffset);
            }
            if (mText != null) {
                setTopAndBottomOffset(mText, verticalOffset, mTextScale);
                setLeftAndRightOffset(mText, verticalOffset, mTextScale);
                setViewScale(mText, verticalOffset, mTextScale);
            }
            if (mImg != null) {
                setTopAndBottomOffset(mImg, verticalOffset, mImgScale);
                setLeftAndRightOffset(mImg, verticalOffset, mImgScale);
                setViewScale(mImg, verticalOffset, mImgScale);
            }
        }
    }

    public void setImgTitleMarginTop(int top) {
        if (mImg != null) {
            getViewOffsetHelper(mImg).setMarginTitleTop(top);
        }
    }

    public void setImgTitleMarginLeft(int left) {
        if (mImg != null) {
            getViewOffsetHelper(mImg).setMarginTitleLeft(left);
        }
    }

    public void setTextTitleMarginTop(int top) {
        if (mText != null) {
            getViewOffsetHelper(mText).setMarginTitleTop(top);
        }
    }

    public void setImgTextMarginLeft(int left) {
        if (mText != null) {
            getViewOffsetHelper(mText).setMarginTitleLeft(left);
        }
    }
}

这是 content_scolling.xml:

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.NestedScrollView
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:background="#cccccc"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="nczz.cn.helloworld.ScrollingActivity"
    tools:showIn="@layout/activity_scrolling">
  <TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/large_text" />

</android.support.v4.widget.NestedScrollView>

这是Java:

package nczz.cn.helloworld;

import android.app.Activity;
import android.content.Intent;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import android.widget.LinearLayout;

public class ScrollingActivity extends Activity {
    LinearLayout titleTxt;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_scrolling);
        initViews();
        setTitleBarHeight();
    }

    private void initViews(){
        titleTxt= (LinearLayout) findViewById(R.id.test_title);
    }


    private void setTitleBarHeight(){
        WindowManager manager=getWindowManager();
        int height=manager.getDefaultDisplay().getHeight();
        ViewGroup.LayoutParams params=titleTxt.getLayoutParams();
        params.height=height/12;
        titleTxt.setLayoutParams(params);
    }
}

Answer 1

我不确定，但你可以根据嵌套 ScrollView 中的 View 使用以下代码

viewlayoutInsidescrollview.setNestedScrollingEnabled(false); 

在java类中