Android 6.0 解决recyclerview 在 scrollview 中不能全部显示，高度不正常的问题。

这个问题困扰了我半天，国内百度上的资料非常的烂。根本无法解决问题。

在android 4 / 5 版本中 scrollview 包含了一个recyclerview 滚动一切正常。

在6.0中不能全部显示。原来是一个BUG

最终 stackoverflow 找到了解决办法：

http://stackoverflow.com/questions/27083091/recyclerview-inside-scrollview-is-not-working

主要代码

https://github.com/amardeshbd/android-recycler-view-wrap-content

This is a sample android app which demonstrates `RecyclerView` wrap_content inside `ScrollView` issue on Marshmallow and Nougat (API 23 & 24) and how to work around it.

在API23 24中不能正常工作。

解决办法：

在 recyclerview 外面再包一层 RelativeLayout

 <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:descendantFocusability="blocksDescendants">
            <!-- DEV NOTE: Outer wrapper relative layout is added intentionally to address issue
                 that only happens on Marshmallow & Nougat devices (API 23 & 24).
                 On marshmallow API 23, the "RecyclerView" `layout_height="wrap_content"` does NOT
                 occupy the height of all the elements added to it via adapter. The result is cut out
                 items that is outside of device viewport when it loads initially.
                 Wrapping "RecyclerView" with "RelativeLayout" fixes the issue on Marshmallow devices.
            -->
            <android.support.v7.widget.RecyclerView
                android:id="@+id/my_recycler_view"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                tools:listitem="@layout/row_list_item">

            </android.support.v7.widget.RecyclerView>

        </RelativeLayout>

 mRecyclerView.setHasFixedSize(true);

        // use a linear layout manager
        mLayoutManager = new LinearLayoutManager(getContext());
        mLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
        mRecyclerView.setLayoutManager(mLayoutManager);

        // Disabled nested scrolling since Parent scrollview will scroll the content.
        mRecyclerView.setNestedScrollingEnabled(false);

        // specify an adapter (see also next example)
        mAdapter = new SimpleListAdapter(DataSetProvider.generateDataset());
        mRecyclerView.setAdapter(mAdapter);

问题终于解决。还是stackoverflow靠谱