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    copied!<p>There are many ways to implement drag/drop in WPF, and none of them are really trivial. For example you could:</p> <ul> <li>Add <a href="http://msdn.microsoft.com/en-us/library/system.windows.controls.primitives.thumb%28v=vs.100%29.aspx" rel="nofollow">Thumbs</a> to a Canvas and implement dragstart, dragcomplete and dragdelta</li> <li>Use Adorners. Good article <a href="http://www.zagstudio.com/blog/488#.Ug3agpLIapc" rel="nofollow">here</a>.</li> <li>Use RenderTransform and create a TranslateTransform to move the control. And manually implement mousedown, mousemove and mouseup on your window/usercontrol.</li> </ul> <p>The following code uses the RenderTransform property of runtime generated Labels to move them around on the screen as the user drags them with the mouse. A limitation of my example is that you cannot have other transforms applied to your labels because it will be overwritten. Consider using a TransformGroup.</p> <p><strong>Xaml</strong></p> <pre><code>&lt;Window x:Class="WpfApplication2.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="MainWindow" Height="350" Width="525" Background="Gray" PreviewMouseLeftButtonDown="Window_PreviewMouseLeftButtonDown" PreviewMouseMove="Window_PreviewMouseMove" PreviewMouseLeftButtonUp="Window_PreviewMouseLeftButtonUp"&gt; &lt;Grid&gt; &lt;ItemsControl ItemsSource="{Binding LabelsCollection}"&gt; &lt;ItemsControl.ItemsPanel&gt; &lt;ItemsPanelTemplate&gt; &lt;StackPanel /&gt; &lt;/ItemsPanelTemplate&gt; &lt;/ItemsControl.ItemsPanel&gt; &lt;ItemsControl.ItemTemplate&gt; &lt;DataTemplate&gt; &lt;Label HorizontalAlignment="Center" Content="{Binding}"&gt;&lt;/Label&gt; &lt;/DataTemplate&gt; &lt;/ItemsControl.ItemTemplate&gt; &lt;/ItemsControl&gt; &lt;/Grid&gt; </code></pre> <p></p> <p><strong>Code behind</strong></p> <pre><code>public partial class MainWindow : Window, INotifyPropertyChanged { private List&lt;DependencyObject&gt; _hitResultsList = new List&lt;DependencyObject&gt;(); private Point _currentlyDraggedMouseOffset; private Label _currentlyDragged; private ObservableCollection&lt;string&gt; _labelsCollection; public event PropertyChangedEventHandler PropertyChanged; public MainWindow() { DataContext = this; InitializeComponent(); LabelsCollection = new ObservableCollection&lt;string&gt;(); for (int i = 1; i &lt;= 10; i++) { LabelsCollection.Add("Label " + i); } } public ObservableCollection&lt;string&gt; LabelsCollection { get { return _labelsCollection; } set { _labelsCollection = value; if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs("LabelsCollection")); } } } private void Window_PreviewMouseMove(object sender, MouseEventArgs e) { if (_currentlyDragged != null) { var mousePos = e.GetPosition(this); _currentlyDragged.RenderTransform = new TranslateTransform(mousePos.X - _currentlyDraggedMouseOffset.X, mousePos.Y - _currentlyDraggedMouseOffset.Y); } } private void Window_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e) { _currentlyDragged = null; ReleaseMouseCapture(); } private void Window_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e) { CaptureMouse(); Point pt = e.GetPosition((UIElement)sender); _hitResultsList.Clear(); VisualTreeHelper.HitTest(this, null, new HitTestResultCallback(MyHitTestResult), new PointHitTestParameters(pt)); if (_hitResultsList.Count &gt; 0) { foreach (DependencyObject d in _hitResultsList) { var parent = VisualTreeHelper.GetParent(d); if (parent != null &amp;&amp; parent is Label) { _currentlyDragged = parent as Label; if (_currentlyDragged.RenderTransform is TranslateTransform) { _currentlyDraggedMouseOffset.X = e.GetPosition(this).X - ((TranslateTransform)_currentlyDragged.RenderTransform).X; _currentlyDraggedMouseOffset.Y = e.GetPosition(this).Y - ((TranslateTransform)_currentlyDragged.RenderTransform).Y; } else { _currentlyDraggedMouseOffset.X = pt.X; _currentlyDraggedMouseOffset.Y = pt.Y; } return; } } } _currentlyDragged = null; } // Return the result of the hit test to the callback. public HitTestResultBehavior MyHitTestResult(HitTestResult result) { _hitResultsList.Add(result.VisualHit); return HitTestResultBehavior.Continue; } } </code></pre>
 

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