Android-通讯录:在群发短信选取联系人界面用到的自定义viewgroup

class MyViewGroup extends ViewGroup {

	private final static int VIEW_MARGIN = 2;
	private int maxWidth = 0;
	private int maxHeight = 60;

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

	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

		for (int index = 0; index < getChildCount(); index++) {
			final View child = getChildAt(index);
			child.measure(MeasureSpec.UNSPECIFIED, MeasureSpec.UNSPECIFIED);
		}
		super.onMeasure(widthMeasureSpec, heightMeasureSpec);
	}

	protected void onLayout(boolean arg0, int arg1, int arg2, int arg3, int arg4) {

		final int count = getChildCount();
		int row = 0;// which row lay you view relative to parent
		int lengthX = arg1;    // right position of child relative to parent
		int lengthY = arg2;    // bottom position of child relative to parent
		for(int i = 0 ; i < count ; i++){

			final View child = this.getChildAt(i);
			int width = child.getMeasuredWidth();
			//            int height = child.getMeasuredHeight();
			int height = maxHeight; //限制子节点的高度
			lengthX += width + VIEW_MARGIN;

			lengthY = row * (height + VIEW_MARGIN) + VIEW_MARGIN + height + arg2;
			if(width + VIEW_MARGIN > maxWidth){
				maxWidth = width + VIEW_MARGIN;
			}

			if(lengthX > arg3){
				lengthX = width + VIEW_MARGIN + arg1;
				row ++;
				lengthY = row * (height + VIEW_MARGIN) + VIEW_MARGIN + height + arg2;

			}
			child.layout(lengthX - width, lengthY - height, lengthX, lengthY);
		}
	}

}