关于Scrollview嵌套RecyclerView高度显示不全

2019-11-06 09:56:26

字体：大中小

来源：转载

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前言

转载请注明出处：http://blog.csdn.net/dreamsever/article/details/58117072

做 Android开发我们经常会遇到这种ScrollView嵌套Listview或者嵌套RecyclerView的需求，当我们搜索解决方案时经常会遇到这句话

you should never put a scrollable view inside another scrollable view

虽然很多人不推荐这种方法，但是总有一些人（比如我）面对产品设计的一些奇葩界面不得不采用这种方案，今天我就把我找到的Scrollview嵌套Recyclerview高度显示不全解决办法总结一下。（ScrollView嵌套Listview的情况也是老生常谈的话题，网上太多就不再赘述）

首先

网上已经有前人给我们写出了一个自定义的LinearLayoutManager，我相信你也可以搜索到，下面我先粘贴出来，感兴趣建议好好看看这个类的源码，不要只做搬运工，知其然也要知其所以然，但是使用中会遇到一些小问题，下面讲解

/** * 工具类用于Scrollview嵌套recyclerview * 2017 2 17加入 */public class FullyLinearLayoutManager extends LinearLayoutManager { PRivate static final String TAG = FullyLinearLayoutManager.class.getSimpleName(); public FullyLinearLayoutManager(Context context) { super(context); } public FullyLinearLayoutManager(Context context, int orientation, boolean reverseLayout) { super(context, orientation, reverseLayout); } private int[] mMeasuredDimension = new int[2]; @Override public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state, int widthSpec, int heightSpec) { final int widthMode = View.MeasureSpec.getMode(widthSpec); final int heightMode = View.MeasureSpec.getMode(heightSpec); final int widthSize = View.MeasureSpec.getSize(widthSpec); final int heightSize = View.MeasureSpec.getSize(heightSpec); Log.i(TAG, "onMeasure called. /nwidthMode " + widthMode + " /nheightMode " + heightSpec + " /nwidthSize " + widthSize + " /nheightSize " + heightSize + " /ngetItemCount() " + getItemCount()); int width = 0; int height = 0; for (int i = 0; i < getItemCount(); i++) { measureScrapChild(recycler, i, View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED), View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED), mMeasuredDimension); if (getOrientation() == HORIZONTAL) { width = width + mMeasuredDimension[0]; if (i == 0) { height = mMeasuredDimension[1]; } } else { height = height + mMeasuredDimension[1]; if (i == 0) { width = mMeasuredDimension[0]; } } } switch (widthMode) { case View.MeasureSpec.EXACTLY: width = widthSize; case View.MeasureSpec.AT_MOST: case View.MeasureSpec.UNSPECIFIED: } switch (heightMode) { case View.MeasureSpec.EXACTLY: height = heightSize; case View.MeasureSpec.AT_MOST: case View.MeasureSpec.UNSPECIFIED: } setMeasuredDimension(width, height); } private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec, int heightSpec, int[] measuredDimension) { try { View view = recycler.getViewForPosition(0);//fix 动态添加时报IndexOutOfBoundsException if (view != null) { RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams(); int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, getPaddingLeft() + getPaddingRight(), p.width); int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, getPaddingTop() + getPaddingBottom(), p.height); view.measure(childWidthSpec, childHeightSpec); measuredDimension[0] = view.getMeasuredWidth() + p.leftMargin + p.rightMargin; measuredDimension[1] = view.getMeasuredHeight() + p.bottomMargin + p.topMargin; recycler.recycleView(view); } } catch (Exception e) { e.printStackTrace(); } finally { } }}

小问题，值得注意的地方

1，

给scrollview加入一个属性

android:fillViewport="true"

处理滑动冲突情况，如下设置

recyclerView.setNestedScrollingEnabled(false);

我开始用的scrollview，测试设备：小米note黑 adnroid6.0,由于我的里面有两个RecyclerView我发现下面的超出屏幕的部分就不显示了，其他的机型是可以的。网上搜索建议将Scrollview换成android.support.v4.widget.NestedScrollView，我试了一下确实正常工作了