如何在 recyclerview 中仅显示 2 个适合 x 和 y 的网格项？

Question

我有一个RecyclerView，它显示在fragment 内，网格Layoutmanager。我的问题是如何在屏幕的一半中显示一个网格项？

我只想显示 2 列，它们的高度相同。

这是我的网格项（代表一个网格项）：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.v7.widget.CardView
        android:id="@+id/cardViewGridItemXml"
        android:layout_width="300dp"
        android:layout_height="wrap_content"
        card_view:cardCornerRadius="3dp"
        android:layout_marginTop="3dp"
        android:layout_marginLeft="5dp"
        android:layout_marginRight="5dp"
        card_view:cardElevation="0.01dp"
        android:layout_marginBottom="0dp">

        <RelativeLayout
            android:id="@+id/topLayoutGridItemXml"
            android:layout_width="165dp"
            android:layout_height="160dp">

            <ImageView
                android:id="@+id/imgTumbnailGridItemXml"
                android:layout_width="wrap_content"
                android:layout_height="150dp"
                android:scaleType="fitXY"
                android:layout_above="@+id/txtTitleGridItemXml"
                android:src="@drawable/leopard"
                />

            <TextView
                android:id="@+id/txtTitleGridItemXml"
                android:layout_width="fill_parent"
                android:layout_height="40dp"
                android:paddingLeft="5dp"
                android:paddingRight="2dp"
                android:layout_gravity="bottom"
                android:background="#ff444444"
                android:textColor="#fff"
                android:textSize="20dp"
                android:text="Test"
                android:layout_alignParentBottom="true"
                android:layout_alignParentLeft="true"
                android:layout_alignParentStart="true"
                />


        </RelativeLayout>



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

</LinearLayout>

这是我的GridLayoutManager：

 GridLayoutManager  gridLayoutManager = new GridLayoutManager(getActivity(), 2);
 recyclerView.setLayoutManager(gridLayoutManager);

Answer 1

用于设置固定列数

 GridLayoutManager  gridLayoutManager = new GridLayoutManager(getActivity(), 2);
 gridLayoutManager.setSpanCount(NUMBER_OF_COLUMN_YOU_NEED);
 recyclerView.setLayoutManager(gridLayoutManager);

公共无效 setSpanCount(int spanCount)
设置要布局的跨度数。
如果getOrientation() 是VERTICAL，这是列数。
如果getOrientation() 是HORIZONTAL，这是行数。

Answer 2

首先创建一个用于回收的xml文件

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
             android:orientation="vertical"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             android:foreground="?android:attr/selectableItemBackground">

    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
                  android:orientation="vertical"
                  android:layout_width="match_parent"
                  android:layout_height="match_parent"
                    android:layout_marginTop="30dp"
                  android:padding="@dimen/spacing_xsmall">


        <com.swoquix.developer.kumbhevents.widgets.SquareImageView
            android:id="@+id/image"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="@android:color/black"
            android:scaleType="centerCrop"/>

        <TextView
            android:id="@+id/text"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:padding="@dimen/spacing_large"
            android:textColor="@android:color/white"
            android:background="@android:color/black"/>

    </LinearLayout>

</FrameLayout>

现在取决于您如何从 JSON 或本地数据库中获取数据。根据您的需要创建您的适配器类，然后创建自定义 GridRecyclerView 类如下：-

public class GridRecyclerView extends RecyclerView {

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

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

    public GridRecyclerView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @Override
    public void setLayoutManager(LayoutManager layout) {
        if (layout instanceof GridLayoutManager) {
            super.setLayoutManager(layout);
        } else {
            throw new ClassCastException("You should only use a GridLayoutManager with GridRecyclerView.");
        }
    }

    @Override
    protected void attachLayoutAnimationParameters(View child, @NonNull ViewGroup.LayoutParams params, int index, int count) {
    if (getAdapter() != null && getLayoutManager() instanceof GridLayoutManager) {

        GridLayoutAnimationController.AnimationParameters animationParams =
                (GridLayoutAnimationController.AnimationParameters) params.layoutAnimationParameters;

        if (animationParams == null) {
            animationParams = new GridLayoutAnimationController.AnimationParameters();
            params.layoutAnimationParameters = animationParams;
        }

        int columns = ((GridLayoutManager) getLayoutManager()).getSpanCount();

        animationParams.count = count;
        animationParams.index = index;
        animationParams.columnsCount = columns;
        animationParams.rowsCount = count / columns;

        final int invertedIndex = count - 1 - index;
        animationParams.column = columns - 1 - (invertedIndex % columns);
        animationParams.row = animationParams.rowsCount - 1 - invertedIndex / columns;

    } else {
        super.attachLayoutAnimationParameters(child, params, index, count);
    }
}

}

接下来你想做的。将代码粘贴到您的 MainActivity

 recyclerView = (RecyclerView) findViewById(R.id.recycler);
        recyclerView.setLayoutManager(new GridLayoutManager(this, 2));

我想你找到了答案。