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WPF:通过DependencyObject限制拖动操作的有效控制部分

drag-and-drop user-controls wpf

0

Chris Holmes · 技术社区 · 17 年前

我在读完之后问这个问题 this answer

<UserControl x:Class="WpfTest.UserControl1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Height="300" Width="300">
    <Border Background="Blue">
        <Grid>
            <Grid.ColumnDefinitions>

            </Grid.ColumnDefinitions>
            <Grid.RowDefinitions>
                <RowDefinition Height="26"></RowDefinition>
                <RowDefinition Height="*"></RowDefinition>
            </Grid.RowDefinitions>
            <Canvas Grid.Row="0" Background="orange"></Canvas>
            <Canvas Grid.Row="1" Background="Purple"></Canvas>
        </Grid>
    </Border>
</UserControl>

3 回复 | 直到 9 年前

1

Robert Macnee 17 年前

DraggableExtender.CanDrag

<UserControl x:Class="WpfTest.UserControl1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Width="300" Height="300">
    <UserControl.Style>
        <Style>
            <Setter Property="(DraggableExtender.CanDrag)" Value="False"/>
            <Style.Triggers>
                <DataTrigger Binding="{Binding IsMouseOver, ElementName=headerCanvas}" Value="True">
                    <Setter Property="(drag:DraggableExtender.CanDrag)" Value="True"/>
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </UserControl.Style>
    <Border Background="Blue">
        <Grid>
            <Grid.ColumnDefinitions>
            </Grid.ColumnDefinitions>
            <Grid.RowDefinitions>
                <RowDefinition Height="26"></RowDefinition>
                <RowDefinition Height="*"></RowDefinition>
            </Grid.RowDefinitions>
            <Canvas x:Name="headerCanvas" Grid.Row="0" Background="orange"></Canvas>
            <Canvas Grid.Row="1" Background="Purple"></Canvas>
        </Grid>
    </Border>
</UserControl>

2

1

Chris Holmes 17 年前

.

<UserControl x:Class="WpfTest.UserControl1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Height="300" Width="300">
    <Border Background="Blue">
        <Grid>
            <Grid.ColumnDefinitions>

            </Grid.ColumnDefinitions>
            <Grid.RowDefinitions>
                <RowDefinition Height="26"></RowDefinition>
                <RowDefinition Height="*"></RowDefinition>
            </Grid.RowDefinitions>
            <Canvas Grid.Row="0" Background="orange"></Canvas>
            <Thumb Grid.Row="0" Background="Cyan" DragCompleted="OnDragComplete" DragStarted="OnDragStarted" DragDelta="OnDragDelta" ></Thumb>
            <Canvas Grid.Row="1" Background="Purple"></Canvas>
        </Grid>
    </Border>
</UserControl>

public partial class UserControl1 : UserControl
    {
        private bool _isDragging;
        private double _x;
        private double _y;

        public UserControl1()
        {
            InitializeComponent();
        }

        private void OnDragComplete(object sender, DragCompletedEventArgs e)
        {
            _isDragging = false;

        }

        private void OnDragStarted(object sender, DragStartedEventArgs e)
        {
            _isDragging = true;

            _x = (double)GetValue(Canvas.LeftProperty);
            _y = (double)GetValue(Canvas.TopProperty);

        }

        private void OnDragDelta(object sender, DragDeltaEventArgs e)
        {
            if (!_isDragging) return;

            _x += e.HorizontalChange;
            _y += e.VerticalChange;


            SetValue(Canvas.LeftProperty,_x );
            SetValue(Canvas.TopProperty,_y );
        }
    }

3

-1

jeff 17 年前

我在CodeProject上找到了一个非常好的例子,叫做DiagramDesigner。这应该能让你朝着正确的方向开始。 CodeProject, DiagramDesigner4