recycleview ItemDecora 添加内容

要向RecyclerView的Item添加装饰内容，你可以使用RecyclerView的ItemDecoration类。以下是一个示例代码，演示如何添加分割线作为装饰内容：

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.drawable.Drawable;
import android.view.View;

import androidx.annotation.DrawableRes;
import androidx.core.content.ContextCompat;
import androidx.recyclerview.widget.RecyclerView;

public class DividerItemDecoration extends RecyclerView.ItemDecoration {
    private Drawable divider;

    public DividerItemDecoration(Context context, @DrawableRes int resId) {
        divider = ContextCompat.getDrawable(context, resId);
    }

    @Override
    public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
        int left = parent.getPaddingLeft();
        int right = parent.getWidth() - parent.getPaddingRight();

        int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            View child = parent.getChildAt(i);

            RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();

            int top = child.getBottom() + params.bottomMargin;
            int bottom = top + divider.getIntrinsicHeight();

            divider.setBounds(left, top, right, bottom);
            divider.draw(c);
        }
    }
}

你可以在你的RecyclerView中使用这个ItemDecoration类，示例如下：

RecyclerView recyclerView = findViewById(R.id.recyclerView);
recyclerView.addItemDecoration(new DividerItemDecoration(this, R.drawable.divider));

上述代码假设你已经在res/drawable文件夹中添加了一个名为"divider"的分割线资源文件。你可以根据自己的需求更改分割线的样式和颜色。

希望这能帮到你！如果你还有其他问题，请继续提问。