import android.content.Context;

import android.util.AttributeSet;

import android.view.View;

import android.widget.RadioGroup;

/**

 * 流式布局的RadioGroup

 */

public class FlowRadioGroup extends RadioGroup {

    public FlowRadioGroup(Context context) {

        super(context);

    }

    public FlowRadioGroup(Context context, AttributeSet attrs) {

        super(context, attrs);

    }

    @Override

    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

        int maxWidth = MeasureSpec.getSize(widthMeasureSpec);

        int childCount = getChildCount();

        int x = 0;

        int y = 0;

        int row = 0;

        for (int index = 0; index < childCount; index++) {

            final View child = getChildAt(index);

            if (child.getVisibility() != View.GONE) {

                child.measure(MeasureSpec.UNSPECIFIED, MeasureSpec.UNSPECIFIED);

                // 此处增加onlayout中的换行判断，用于计算所需的高度

                int width = child.getMeasuredWidth();

                int height = child.getMeasuredHeight();

                x += width;

                y = row * height + height;

                if (x > maxWidth) {

                    x = width;

                    row++;

                    y = row * height + height;

                }

            }

        }

        // 设置容器所需的宽度和高度

        setMeasuredDimension(maxWidth, y);

    }

    @Override

    protected void onLayout(boolean changed, int l, int t, int r, int b) {

        final int childCount = getChildCount();

        int maxWidth = r - l;

        int x = 0;

        int y = 0;

        int row = 0;

        for (int i = 0; i < childCount; i++) {

            final View child = this.getChildAt(i);

            if (child.getVisibility() != View.GONE) {

                int width = child.getMeasuredWidth();

                int height = child.getMeasuredHeight();

                x += width;

                y = row * height + height;

                if (x > maxWidth) {

                    x = width;

                    row++;

                    y = row * height + height;

                }

                child.layout(x - width, y - height, x, y);

            }

        }

    }

}