RadioButton实现自动换行的效果

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) {
//获取最大宽度
int maxWidth = MeasureSpec.getSize(widthMeasureSpec);
//获取Group中的Child数量
int childCount = getChildCount();
//设置Group的左边距，下面也会使用x计算每行所占的宽度
int x = 0;
//设置Group的上边距，下面也会使用y计算Group所占的高度
int y = 30;
//设置Group的行数
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);
//重新计算child的宽高
int width = child.getMeasuredWidth();
int height = child.getMeasuredHeight();
//添加到X中，(width+10) 设置child左边距
x += (width + 10);
//行数*child高度+这次child高度=现在Group的高度,(height + 10)设置child上边距
y = row * (height + 10) + (height + 10);
//当前行宽X大于Group的最大宽度时，进行换行
if (x > maxWidth) {
//当index不为0时，进行row++，防止FirstChild出现大于maxWidth时,提前进行row++
if (index != 0)
row++;
//child的width大于maxWidth时，重新设置child的width为最大宽度
if (width >= maxWidth) {
width = maxWidth - 30;
}
//重新设置当前X
x = (width + 20);
//重新设置现在Group的高度
y = row * (height + 10) + (height + 10);
}
}
}
// 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 = 10;
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 + 10);
y = row * (height + 10) + (height + 10);
if (x > maxWidth) {
if (i != 0)
row++;
if (width >= maxWidth) {
width = maxWidth - 30;
}
x = (width + 20);
y = row * (height + 10) + (height + 10);
}
child.layout(x - width, y - height, x, y);
}
}
}
}

源码