我正在构建一个使用RecyclerView
的Android应用程序。我想为RecyclerView
添加分隔符,我使用这段代码做了:
DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(recyclerView.getContext(), linearLayoutManager.getOrientation());
recyclerView.addItemDecoration(dividerItemDecoration);
到目前为止一切正常。但是,分频器的大小是全屏的,我想为它添加边距。有没有办法可以使用一种方法向分隔线添加边距,这种方法会为绘制的矩形添加一些空间,而不是通过创建带边距的自定义可绘制形状并将其添加到RecyclerView
?
使用此选项并根据您的要求进行定制。
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private static final int[] ATTRS = new int[]{android.R.attr.listDivider};
private Drawable divider;
/**
* Default divider will be used
*/
public DividerItemDecoration(Context context) {
final TypedArray styledAttributes = context.obtainStyledAttributes(ATTRS);
divider = styledAttributes.getDrawable(0);
styledAttributes.recycle();
}
/**
* Custom divider will be used
*/
public DividerItemDecoration(Context context, 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);
}
}
}
我认为最直接的解决方案是在装饰对象上使用setDrawable方法,并使用您想要的边距的插入值传递一个插入的drawable。像这样:
int[] ATTRS = new int[]{android.R.attr.listDivider};
TypedArray a = context.obtainStyledAttributes(ATTRS);
Drawable divider = a.getDrawable(0);
int inset = getResources().getDimensionPixelSize(R.dimen.your_margin_value);
InsetDrawable insetDivider = new InsetDrawable(divider, inset, 0, inset, 0);
a.recycle();
DividerItemDecoration itemDecoration = new DividerItemDecoration(context, DividerItemDecoration.VERTICAL);
itemDecoration.setDrawable(insetDivider);
recyclerView.addItemDecoration(itemDecoration);
您可以为回收站视图创建自己的项目装饰。这是相同的代码。
public class SimpleItemDecorator extends RecyclerView.ItemDecoration {
int space;
boolean isHorizontalLayout;
public SimpleItemDecorator(int space) {
this.space = space;
}
public SimpleItemDecorator(int space, boolean isHorizontalLayout) {
this.space = space;
this.isHorizontalLayout = isHorizontalLayout;
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
super.getItemOffsets(outRect, view, parent, state);
if(isHorizontalLayout)
{
outRect.bottom=space;
outRect.right=space;
outRect.left=space;
outRect.top=space;
} else {
outRect.bottom = space;
if (parent.getChildAdapterPosition(view) == 0)
outRect.top = space;
else
outRect.top = 0;
}
}
}
要将它与您的recyclerview一起使用,您可以这样做:
recyclerView.addItemDecoration(new SimpleItemDecorator(5));
和@Vivek的回答一样,但在Kotlin和不同的参数中
class SimpleItemDecorator : RecyclerView.ItemDecoration {
private var top_bottom: Int = 0
private var left_right: Int = 0
/**
* @param top_bottom for top and bottom margin
* @param left_right for left and right margin
*/
constructor(top_bottom: Int, left_right: Int = 0) {
this.top_bottom = top_bottom
this.left_right = left_right
}
override fun getItemOffsets(outRect: Rect, view: View, parent: RecyclerView, state: RecyclerView.State) {
super.getItemOffsets(outRect, view, parent, state)
outRect.bottom = top_bottom
outRect.top = top_bottom
outRect.right = left_right
outRect.left = left_right
}
}