2.9讲的是，如果内部设定超过容器大小，怎么办？
StackPanel会裁剪越界部分
DockPanel和Grid会智能判断，从而决定换行。
2.10 自定义布局容器
自定义容器要实现两个方法MeasureOverride和ArrangeOverride，并保证遍历其下的所有子控件，使他们都执行Measure和Arrange方法。
using System;using System.Windows.Controls;using System.Windows;
namespace CustomPanel 
{
public class DiagonalPanel : Panel {
protected override Size MeasureOverride( Size availableSize ) { double totalWidth = 0; double totalHeight = 0; foreach( UIElement child in Children ) { child.Measure( new Size( double.PositiveInfinity, double.PositiveInfinity ) ); Size childSize = child.DesiredSize; totalWidth += childSize.Width; totalHeight += childSize.Height;
} return new Size( totalWidth, totalHeight ); } protected override Size ArrangeOverride( Size finalSize ) { Point currentPosition = new Point( ); foreach( UIElement child in Children ) { Rect childRect = new Rect( currentPosition, child.DesiredSize ); child.Arrange( childRect ); currentPosition.Offset( childRect.Width, childRect.Height ); } return new Size( currentPosition.X, currentPosition.Y ); } }
}
原文：http://www.cnblogs.com/lonelyxmas/p/4962826.html