宽高自适应的正方形图片展示

//布局

//自定义view

public class SquareLayout extends RelativeLayout {
    public SquareLayout(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

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

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

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

        setMeasuredDimension(getDefaultSize(0, widthMeasureSpec), getDefaultSize(0, heightMeasureSpec));

        // Children are just made to fill our space.
        int childWidthSize = getMeasuredWidth();
        int childHeightSize = getMeasuredHeight();
        //高度和宽度一样
        heightMeasureSpec = widthMeasureSpec = MeasureSpec.makeMeasureSpec(childWidthSize, MeasureSpec.EXACTLY);
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }
}