import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;

/** * 详细说明 * * @author Daniel * @version V1.0 * @date 2019/10/18 * @deprecated 自定义ViewGroup */
public class CustomImgContainer extends ViewGroup {

    public CustomImgContainer(Context context) {
        this(context, null);
    }

    public CustomImgContainer(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

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

    /** * 计算所有ChildView的宽度和高度 然后根据ChildView的计算结果，设置自己的宽和高 * @param widthMeasureSpec * @param heightMeasureSpec */
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        /** * 获得此ViewGroup上级容器为其推荐的宽和高，以及计算模式 */
        int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        int widthSize = MeasureSpec.getSize(widthMeasureSpec);
        int heightMode = MeasureSpec.getMode(heightMeasureSpec);
        int heightSize = MeasureSpec.getSize(heightMeasureSpec);
        // 计算出所有的childView的宽和高
        measureChildren(widthMeasureSpec, heightMeasureSpec);

        int count = getChildCount();
        int cWidth, cHeight;
        MarginLayoutParams cParams;

        // 用于计算左边两个childView的高度
        int lHeight = 0;
        // 用于计算右边两个childView的高度，最终高度取二者之间大值
        int rHeight = 0;

        // 用于计算上边两个childView的宽度
        int tWidth = 0;
        // 用于计算下面两个childiew的宽度，最终宽度取二者之间大值
        int bWidth = 0;

        /** * 根据childView计算的出的宽和高，以及设置的margin计算容器的宽和高，主要用于容器是warp_content时 */
        for (int i = 0; i < count; i++) {
            View child = getChildAt(i);
            cWidth = child.getMeasuredWidth();
            cHeight = child.getMeasuredHeight();
            cParams = (MarginLayoutParams) child.getLayoutParams();

            if (i == 0 || i == 1) {
                tWidth += cWidth + cParams.leftMargin + cParams.rightMargin;
            }
            if (i == 2 || i == 3) {
                bWidth += cWidth + cParams.leftMargin + cParams.rightMargin;
            }
            if (i == 0 || i == 2) {
                lHeight += cHeight + cParams.topMargin + cParams.bottomMargin;
            }
            if (i == 1 || i == 3) {
                rHeight += cHeight + cParams.topMargin + cParams.bottomMargin;
            }
        }

        // 记录如果是wrap_content是设置的宽和高
        int width = Math.max(tWidth, bWidth);
        int height = Math.max(lHeight, rHeight);

        /** * 如果是wrap_content设置为我们计算的值 * 否则：直接设置为父容器计算的值 */
        setMeasuredDimension((widthMode == MeasureSpec.EXACTLY) ? widthSize : width, (heightMode == MeasureSpec.EXACTLY) ? heightSize : height);

    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        int count = getChildCount();
        int cWidth, cHeight;
        MarginLayoutParams cParams;
        /** * 遍历所有childView根据其宽和高，以及margin进行布局 */
        for (int i = 0; i < count; i++) {
            View child = getChildAt(i);
            cWidth = child.getMeasuredWidth();
            cHeight = child.getMeasuredHeight();
            cParams = (MarginLayoutParams) child.getLayoutParams();

            int cl = 0, ct = 0, cr = 0, cb = 0;
            switch (i) {
                case 0:
                    cl = cParams.leftMargin;
                    ct = cParams.topMargin;
                    break;
                case 1:
                    cl = getWidth() - cWidth - cParams.rightMargin;
                    ct = cParams.topMargin;
                    break;
                case 2:
                    cl = cParams.leftMargin;
                    ct = getHeight() - cHeight - cParams.bottomMargin;
                    break;
                case 3:
                    cl = getWidth() - cWidth - cParams.rightMargin;
                    ct = getHeight() - cHeight - cParams.bottomMargin;
                    break;
            }
            cr = cl + cWidth;
            cb = cHeight + ct;
            // 设置Child的位置，左上角和右下角
            child.layout(cl, ct, cr, cb);
        }
    }

    @Override
    public LayoutParams generateLayoutParams(AttributeSet attrs) {
        return new MarginLayoutParams(getContext(), attrs);
    }
}