要实现Android GridLayoutManager中一行只有一个背景图,可以通过自定义RecyclerView的ItemDecoration来实现。以下是示例代码:
public class SingleBackgroundItemDecoration extends RecyclerView.ItemDecoration {
private Drawable background;
public SingleBackgroundItemDecoration(Context context, @DrawableRes int backgroundResId) {
background = ContextCompat.getDrawable(context, backgroundResId);
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
int position = parent.getChildAdapterPosition(view);
int spanCount = ((GridLayoutManager) parent.getLayoutManager()).getSpanCount();
if (position % spanCount == 0) {
outRect.left = 0;
outRect.right = parent.getWidth() - parent.getPaddingRight();
} else {
outRect.left = parent.getWidth();
outRect.right = 0;
}
}
@Override
public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
int spanCount = ((GridLayoutManager) parent.getLayoutManager()).getSpanCount();
int childCount = parent.getChildCount();
for (int i = 0; i < childCount; i++) {
View child = parent.getChildAt(i);
int position = parent.getChildAdapterPosition(child);
if (position % spanCount == 0) {
background.setBounds(child.getLeft(), child.getTop(), child.getRight(), child.getBottom());
background.draw(c);
}
}
}
}
RecyclerView recyclerView = findViewById(R.id.recycler_view);
recyclerView.setLayoutManager(new GridLayoutManager(this, spanCount));
recyclerView.addItemDecoration(new SingleBackgroundItemDecoration(this, R.drawable.background));
在这个示例中,我们假设你的背景图资源文件为background
,你可以根据自己的需求修改背景图的资源和布局逻辑。