Android - 像标签一样堆叠项目

Question

我有什么:

我想做什么:

每当我添加项目时，我都希望将它放在之前的项目旁边。如果一个元素在屏幕的末尾:我希望它被放置在下一行。
在 CSS 中类似于 float: left。

Answer 1

如果你希望你的标签容器最终滚动，那么使用 RecyclerView和 GridLayoutManager并调用它 setSpanCount(3)。不要忘记将其方向设置为 VERTICAL

如果您永远不需要滚动项目，那么只需使用 GridLayout

编辑:

我已经按照您想要的方式整理了粗略的示例。您可能还需要考虑边距和填充，但这应该是您如何做到这一点的基本思路。

public class TagLayout extends ViewGroup {

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

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

public TagLayout(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
}

public TagLayout(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
    super(context, attrs, defStyleAttr, defStyleRes);
}

@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
    int maxWidth = getMeasuredWidth();
    int count = getChildCount();

    int tagLeft = left,
        tagTop = top,
        tagRight = 0,
        tagBottom = 0;

    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {

            tagRight = tagLeft + child.getMeasuredWidth();
            tagBottom = tagTop + child.getMeasuredHeight();

            if (tagRight > maxWidth) {
                tagLeft = left;
                tagRight = left + child.getMeasuredWidth();
                tagTop = tagBottom;
                tagBottom += child.getMeasuredHeight();
            }
            child.layout(tagLeft, tagTop, tagRight, tagBottom);
            tagLeft = left;
        }

    }
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

    int width = 0;
    int height = 0;
    int count = getChildCount();
    int maxWidth = MeasureSpec.getSize(widthMeasureSpec);

    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            measureChild(child, widthMeasureSpec, heightMeasureSpec);
            width += child.getMeasuredWidth();
            if (height == 0) {
                height += child.getMeasuredHeight();
            }
            if (width <= maxWidth) {
                continue;
            } else {
                width = 0;
                height += child.getMeasuredHeight();
            }
        }

    }
    setMeasuredDimension(widthMeasureSpec, MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY));
}

}