Question

我在另一个recyclerview中有一个recyclerview。我想制作内部回收视频的高度＆＃34; warp_content＆＃34;。

我发现可以使用下面提到的新版本的recyclerview。

'com.android.support:recyclerview-v7:23.2.0'

但问题是，通过设置height = wrap_content，我只能看到第一项。

任何帮助都会很棒。

Answer 1

因为我使用RecyclerView这不起作用，请参阅：

https://code.google.com/p/android/issues/detail?id=74772

和

嵌套的Recycler视图高度不会包含它的内容

在这两个页面上，人们建议延长LinearLayoutManager并覆盖onMeasure()

RecyclerView默认没有wrap_content。您必须将RecyclerView与wrap_content布局管理器一起使用，例如WrapLinearLayoutManager，例如CustomLinearLayoutManager。

CustomLinearLayoutManager.java

    public class CustomLinearLayoutManager extends LinearLayoutManager {

private static final String TAG = CustomLinearLayoutManager.class.getSimpleName();

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

public CustomLinearLayoutManager(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);

    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();
    } 
}

}

Answer 2

设置recyclerview项目对我有用。有意添加外部包装器相对布局以解决问题layout_height="wrap_content"没有占用通过适配器添加到其中的所有元素的高度。结果被删除了最初加载时在设备视口外部的项目。使用“RelativeLayout”包装“RecyclerView”可以解决Marshmallow设备上的问题。

<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:descendantFocusability="blocksDescendants">

<android.support.v7.widget.RecyclerView
    android:id="@+id/rv_test"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    tools:listitem="@layout/test_item"></android.support.v7.widget.RecyclerView>
</RelativeLayout>

设置Inner RecyclerView的高度wrap_content

2 个答案: