WPF 创建自定义窗体

在前面的一篇博客"WPF 自定义Metro Style窗体"，展示了如何创建一个类似于Metro Style的Window，并在程序中使用。但是这个窗体不能够*的改变大小。今天的博客中将展示如何创建一个可以通过拖拽来改变大小的Metro Style窗体。

实现思路，在Windows ControlTemplate中增加8个背景透明Rectangle，分别放置于Left, Right, Top, TopLeft, TopRight, Bottom, BottomLeft, BottomRight这8个位置，

XAML：

    <ControlTemplate x:Key="MetroWindowControlTemplate" TargetType="{x:Type Window}">
<Border BorderThickness="1" BorderBrush="LightBlue" Background="White">
<Grid>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition />
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>

<Rectangle x:Name="MoveableRectangle" Fill="LightGray" Grid.Row="0" Grid.Column="0"/>
<StackPanel Grid.Row="0" Grid.Column="1" Orientation="Horizontal" Background="LightGray">
<Button x:Name="MinimizeButton" Style="{StaticResource WindowButtonStyle}" Content="0" />
<Button x:Name="RestoreButton" Style="{StaticResource WindowButtonStyle}" Content="1" />
<Button x:Name="CloseButton" Style="{StaticResource WindowButtonStyle}" Content="r" />
</StackPanel>
<Grid Background="{TemplateBinding Background}" Grid.Row="1" Grid.ColumnSpan="2" Margin="5,5,5,5">
<AdornerDecorator>
<ContentPresenter/>
</AdornerDecorator>
</Grid>
</Grid>

                <Grid x:Name="ResizeGrid">
<Rectangle
Stroke="{x:Null}"
 Fill="Transparent"
 VerticalAlignment="Top"
 Height="5"
 x:Name="Top"
 Margin="5,0,5,0" />
<Rectangle
Stroke="{x:Null}"
 Fill="Transparent"
 x:Name="Bottom"
 Height="5"
 VerticalAlignment="Bottom"
 Margin="5,0,5,0" />
<Rectangle
Stroke="{x:Null}"
 Fill="Transparent"
 HorizontalAlignment="Left"
 Margin="0,5,0,5"
 Width="5"
 x:Name="Left"/>
<Rectangle
Stroke="{x:Null}"
 Fill="Transparent"
 Margin="0,5,0,5"
 Width="5"
 HorizontalAlignment="Right"
 x:Name="Right" />
<Rectangle
Stroke="{x:Null}"
 Fill="Transparent"
 HorizontalAlignment="Left"
 VerticalAlignment="Bottom"
 Width="5"
 Height="5"
 x:Name="BottomLeft" />
<Rectangle
Stroke="{x:Null}"
 Fill="Transparent"
 VerticalAlignment="Bottom"
 Height="5"
 Width="5"
 HorizontalAlignment="Right"
 x:Name="BottomRight" />
<Rectangle
Stroke="{x:Null}"
 Fill="Transparent"
 HorizontalAlignment="Right"
 Width="5"
 Height="5"
 VerticalAlignment="Top"
 x:Name="TopRight" />
<Rectangle
Stroke="{x:Null}"
 Fill="Transparent"
 HorizontalAlignment="Left"
 Width="6"
 VerticalAlignment="Top"
 Height="5"
 x:Name="TopLeft" />
</Grid>

</Grid>
</Border>
</ControlTemplate>

C#:

    ControlTemplate template = App.Current.FindResource("MetroWindowControlTemplate") as ControlTemplate;

if(template != null)
    {
//....

        Grid resizeGrid = template.FindName("ResizeGrid", this) as Grid;

if(resizeGrid != null)
        {
foreach (UIElement element in resizeGrid.Children)
            {
                Rectangle resizeRectangle = element as Rectangle;
if (resizeRectangle != null)
                {
resizeRectangle.PreviewMouseDown += ResizeRectangle_PreviewMouseDown;
 resizeRectangle.MouseMove += ResizeRectangle_MouseMove;
                }
            }
        }
    }

private void ResizeRectangle_PreviewMouseDown(object sender, MouseButtonEventArgs e)
        {
            Rectangle rectangle = sender as Rectangle;

if(rectangle != null)
            {
switch(rectangle.Name)
                {
case "Top":
                        Cursor = Cursors.SizeNS;
                        ResizeWindow(ResizeDirection.Top);
break;
case "Bottom":
                        Cursor = Cursors.SizeNS;
                        ResizeWindow(ResizeDirection.Bottom);
break;
case "Left":
                        Cursor = Cursors.SizeWE;
                        ResizeWindow(ResizeDirection.Left);
break;
case "Right":
                        Cursor = Cursors.SizeWE;
                        ResizeWindow(ResizeDirection.Right);
break;
case "TopLeft":
                        Cursor = Cursors.SizeNWSE;
                        ResizeWindow(ResizeDirection.TopLeft);
break;
case "TopRight":
                        Cursor = Cursors.SizeNESW;
                        ResizeWindow(ResizeDirection.TopRight);
break;
case "BottomLeft":
                        Cursor = Cursors.SizeNESW;
                        ResizeWindow(ResizeDirection.BottomLeft);
break;
case "BottomRight":
                        Cursor = Cursors.SizeNWSE;
                        ResizeWindow(ResizeDirection.BottomRight);
break;
default:
break;
                }
            }
        }

private void ResizeRectangle_MouseMove(object sender, MouseEventArgs e)
        {
            Rectangle rectangle = sender as Rectangle;

if (rectangle != null)
            {
switch (rectangle.Name)
                {
case "Top":
                        Cursor = Cursors.SizeNS;
break;
case "Bottom":
                        Cursor = Cursors.SizeNS;
break;
case "Left":
                        Cursor = Cursors.SizeWE;
break;
case "Right":
                        Cursor = Cursors.SizeWE;
break;
case "TopLeft":
                        Cursor = Cursors.SizeNWSE;
break;
case "TopRight":
                        Cursor = Cursors.SizeNESW;
break;
case "BottomLeft":
                        Cursor = Cursors.SizeNESW;
break;
case "BottomRight":
                        Cursor = Cursors.SizeNWSE;
break;
default:
break;
                }
            }
        }

        [DllImport("user32.dll", CharSet = CharSet.Auto)]
private static extern IntPtr SendMessage(IntPtr hWnd, UInt32 msg, IntPtr wParam, IntPtr lParam);

private void ResizeWindow(ResizeDirection direction)
        {
            SendMessage(_hwndSource.Handle, 0x112, (IntPtr)(61440 + direction), IntPtr.Zero);
        }

到此为止，就实现了一个可以拖拽改变大小的自定义窗体。

运行效果：

感谢您的阅读，代码点击这里下载。