I'm trying to prevent the WPF Bing Maps control from panning when the user is dragging a pushpin. What I do is that when the user selecting the pushpin with the MouseLeftButtonDown I'm, taking over the events from the map ViewChangeStart, ViewChangeOnFrame and set the e.Handled property to true.
What I was expecting is that if I set the property to true the events are canceled and panning is disabled. However the map is still panning.
Another approach what I tried is setting the property SupportedManipulations to None. Both options don't have the expected results.
Below is the code that I'm using for my DraggablePushpin
public class DraggablePushpin : Pushpin
{
private bool isDragging = false;
protected override void OnPreviewMouseLeftButtonDown(System.Windows.Input.MouseButtonEventArgs e)
{
var parentLayer = this.Parent as MapLayer;
if (parentLayer != null)
{
Map parentMap = parentLayer.Tag as Map;
if (parentMap != null)
{
parentMap.ViewChangeStart += parentMap_ViewChangeStart;
parentMap.MouseLeftButtonUp += parentMap_MouseLeftButtonUp;
parentMap.MouseMove += parentMap_MouseMove;
parentMap.SupportedManipulations = System.Windows.Input.Manipulations.Manipulations2D.None;
}
}
this.isDragging = true;
base.OnPreviewMouseLeftButtonDown(e);
}
protected override void OnMouseLeftButtonDown(System.Windows.Input.MouseButtonEventArgs e)
{
base.OnMouseLeftButtonDown(e);
}
void parentMap_MouseMove(object sender, System.Windows.Input.MouseEventArgs e)
{
var map = sender as Map;
// Check if the user is currently dragging the Pushpin
if (this.isDragging)
{
// If so, the Move the Pushpin to where the Mouse is.
var mouseMapPosition = e.GetPosition(map);
var mouseGeocode = map.ViewportPointToLocation(mouseMapPosition);
this.Location = mouseGeocode;
}
}
void parentMap_MouseLeftButtonUp(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
(sender as Map).SupportedManipulations = System.Windows.Input.Manipulations.Manipulations2D.All;
}
protected override void OnMouseLeftButtonUp(System.Windows.Input.MouseButtonEventArgs e)
{
var parentLayer = this.Parent as MapLayer;
if (parentLayer != null)
{
Map parentMap = parentLayer.Tag as Map;
if (parentMap != null)
{
parentMap.SupportedManipulations = System.Windows.Input.Manipulations.Manipulations2D.All;
}
}
}
void parentMap_ViewChangeStart(object sender, MapEventArgs e)
{
if (this.isDragging)
{
e.Handled = true;
}
}
}
Related
I want to get mouse position of container while dragging controls inside so I can add auto-scroll logic to container. However, MouseMove does not fired at all when dragging, DragOver fired only when dragging over controls inside.
test example
Draggable gizmo:
public class Gizmo : TextBlock
{
public Gizmo()
{
this.AllowDrop = true;
this.Background = Brushes.Gray;
this.Margin = new System.Windows.Thickness(6);
}
public Gizmo(string content) : this()
{
this.Text = content;
}
private bool isDragging;
private Point lastPressedLocation;
protected override void OnPreviewMouseMove(System.Windows.Input.MouseEventArgs e)
{
if (e.LeftButton == System.Windows.Input.MouseButtonState.Pressed)
{
if (!this.isDragging)
{
Point newLocation = e.GetPosition(this);
Vector offset = this.lastPressedLocation - newLocation;
if (offset.LengthSquared > 36)
{
this.lastPressedLocation = newLocation;
this.isDragging = true;
System.Windows.DragDrop.DoDragDrop(this, DateTime.Now, DragDropEffects.Move);
}
else
{
this.isDragging = false;
}
}
}
}
private bool canDrop;
protected override void OnPreviewDragEnter(DragEventArgs e)
{
Console.WriteLine("drag enter inside");
if (this.Text == "gizmo 1")
{
e.Effects = DragDropEffects.Move;
this.canDrop = true;
}
else
{
e.Effects = DragDropEffects.None;
this.canDrop = false;
}
e.Handled = true;
base.OnPreviewDragEnter(e);
}
protected override void OnPreviewDragOver(DragEventArgs e)
{
Console.WriteLine("drag over inside");
if (this.canDrop)
{
e.Effects = DragDropEffects.Move;
}
else
{
e.Effects = DragDropEffects.None;
e.Handled = true;
}
base.OnPreviewDragOver(e);
}
}
container:
public class Container : WrapPanel
{
protected override void OnInitialized(EventArgs e)
{
for (int i = 1; i <= 16; i++)
this.Children.Add(new Gizmo(string.Format("gizmo {0}", i)));
base.OnInitialized(e);
}
protected override void OnPreviewDragEnter(System.Windows.DragEventArgs e)
{
Console.WriteLine("drag enter outside");
base.OnPreviewDragEnter(e);
}
protected override void OnPreviewDragOver(System.Windows.DragEventArgs e)
{
//I want to get mouse postion here, but this will be called only when dragging over gizmo inside
Console.WriteLine("drag over outside");
base.OnPreviewDragOver(e);
}
}
running result and question
or it's just impossible?
The last function in your code should work. Alternatively (since there should be no other elements handling the event before you) you can use the OnDragOver method instead of the Preview.
protected override void OnDragOver(DragEventArgs e)
{
Point position = e.GetPosition(this);
}
If it doesn't work, that usually means that specific area of your control is not hit-test visible. Make sure IsHitTestVisible is true (has to be, otherwise child elements wouldn't work either) and that the Background of your control is not null. If you want no background and still be able to be hit-test visible, use Transparent for the background.
Custom sorting and column resize does not work.
Implemented custom sorting on MouseUp event handler however
if ( hitInfo.InColumnPanel && hitInfo.HitTest == GridHitTest.ColumnEdge)
{
(e as DXMouseEventArgs).Handled = true;
return;
}
does not work for the event.
Would like to be able to click on the column header to sort and resize by dragging column edge.
private void OnMouseDown(object sender, MouseEventArgs e)
{
GridHitInfo hitInfo = gridView1.CalcHitInfo(e.Location);
if (hitInfo.HitTest == GridHitTest.ColumnEdge)
{
isEdgeClicked = true;
}
}
private void OnMouseUp(object sender, System.Windows.Forms.MouseEventArgs e)
{
if (isEdgeClicked)
{ isEdgeClicked = false;
return;
}
else
{
(e as DXMouseEventArgs).Handled = true;
}
}
Microsoft Blend allows changing numeric values of properties like Left, Top etc. through continuous drag. User clicks in the property value box, keeps the button down and drags left or right to decrease/increase the value. Simple.
The special thing about it is that if cursor reaches the left or right end of the screen and user still wants to drag more, they can continue dragging and the cursor will start over from the other end of the screen.
I'm trying to do this in one of my WPF applications using Thumb control. Using DragDetla event, if I find that the Thumb has reach the edge of the screen, I set its position to the far end. But this makes the value of e.HorizontalChange as big as the width of entire screen. How can I change Thumb's position during drag without affecting horizontal change value?
I have realized this in a WPF control by using a textbox and subscribing to events such as:
PreviewMouseDown
MouseUp and
MouseMove
MouseEnter
The drag until you reach screen limits requires a mouse capture or call to CaptureMouse method available on any UIElement. On the other side, you need to release the mouse at some point which requires a call of the ReleaseMouseCapture method. The solution could go like this:
Declare an enumeration to model the drag direction
internal enum MouseDirections
{
None,
LeftRight,
UpDown
}
Declare a class to keep trak of mouse origin (first location) and current location:
internal class MouseIncrementor
{
private MouseDirections _enumMouseDirection = MouseDirections.None;
private Point _objPoint;
private readonly Point _initialPoint;
public MouseIncrementor(Point objPoint, MouseDirections enumMouseDirection)
{
_objPoint = objPoint;
_initialPoint = _objPoint;
_enumMouseDirection = enumMouseDirection;
}
public MouseDirections MouseDirection
{
get
{
return _enumMouseDirection;
}
protected set
{
_enumMouseDirection = value;
}
}
public Point InitialPoint
{
get
{
return _initialPoint;
}
}
public Point Point
{
get
{
return _objPoint;
}
set
{
_objPoint = value;
}
}
internal MouseDirections SetMouseDirection(Point pos)
{
double deltaX = this.Point.X - pos.X;
double deltaY = this.Point.Y - pos.Y;
if (Math.Abs(deltaX) > Math.Abs(deltaY))
MouseDirection = MouseDirections.LeftRight;
else
{
if (Math.Abs(deltaX) < Math.Abs(deltaY))
MouseDirection = MouseDirections.UpDown;
}
return MouseDirection;
}
}
I have a custom control that contains a TextBox named _PART_TextBox:
TextBox _PART_TextBox;
...and field for the MouseIncrementor:
MouseIncrementor _objMouseIncr;
...these are wired up like this:
_PART_TextBox.MouseEnter += _PART_TextBox_MouseEnter;
_PART_TextBox.GotKeyboardFocus += _PART_TextBox_GotKeyboardFocus;
_PART_TextBox.LostKeyboardFocus += _PART_TextBox_LostKeyboardFocus;
_PART_TextBox.MouseMove += _PART_TextBox_MouseMove;
_PART_TextBox.MouseUp += _PART_TextBox_MouseUp;
_PART_TextBox.PreviewMouseDown += _PART_TextBox_PreviewMouseDown;
_PART_TextBox.LostMouseCapture += _PART_TextBox_LostMouseCapture;
and a number of event handlers are required to get this to work:
private void _PART_TextBox_LostMouseCapture(object sender, MouseEventArgs e)
{
_objMouseIncr = null;
}
private void _PART_TextBox_MouseUp(object sender, MouseButtonEventArgs e)
{
if (_objMouseIncr != null)
{
var mouseUpPosition = GetPositionFromThis(e);
if (_objMouseIncr.InitialPoint.Equals(mouseUpPosition))
{
_PART_TextBox.Focus();
}
}
_PART_TextBox.ReleaseMouseCapture();
_objMouseIncr = null;
}
private void _PART_TextBox_PreviewMouseDown(object sender, MouseButtonEventArgs e)
{
if (IsKeyboardFocusWithin == false)
{
_objMouseIncr = new MouseIncrementor(this.GetPositionFromThis(e), MouseDirections.None);
e.Handled = true;
}
}
private void _PART_TextBox_MouseMove(object sender, MouseEventArgs e)
{
// nothing to do here
if (_objMouseIncr == null)
return;
if (e.LeftButton != MouseButtonState.Pressed)
return;
if (CanIncreaseCommand() == false && CanDecreaseCommand() == false)
{
// since we can't parse the value, we are out of here, i.e. user put text in our number box
_objMouseIncr = null;
return;
}
var pos = GetPositionFromThis(e);
double deltaX = _objMouseIncr.Point.X - pos.X;
double deltaY = _objMouseIncr.Point.Y - pos.Y;
if (_objMouseIncr.MouseDirection == MouseDirections.None)
{
// this is our first time here, so we need to record if we are tracking x or y movements
if (_objMouseIncr.SetMouseDirection(pos) != MouseDirections.None)
_PART_TextBox.CaptureMouse();
}
if (_objMouseIncr.MouseDirection == MouseDirections.LeftRight)
{
if (deltaX > 0)
OnDecrement(LargeStepSize);
else
{
if (deltaX < 0)
OnIncrement(LargeStepSize);
}
}
else
{
if (_objMouseIncr.MouseDirection == MouseDirections.UpDown)
{
if (deltaY > 0)
{
if (CanIncreaseCommand() == true)
OnIncrease();
}
else
{
if (deltaY < 0)
{
if (CanDecreaseCommand() == true)
OnDecrease();
}
}
}
}
_objMouseIncr.Point = GetPositionFromThis(e);
}
private Point GetPositionFromThis(MouseEventArgs e)
{
return this.PointToScreen(e.GetPosition(this));
}
private void _PART_TextBox_LostKeyboardFocus(object sender, KeyboardFocusChangedEventArgs e)
{
_objMouseIncr = null;
(sender as TextBox).Cursor = Cursors.ScrollAll;
}
private void _PART_TextBox_MouseEnter(object sender, MouseEventArgs e)
{
if (IsMouseDragEnabled == false)
return;
if (IsKeyboardFocusWithin)
(sender as TextBox).Cursor = Cursors.IBeam;
else
(sender as TextBox).Cursor = Cursors.ScrollAll;
}
private void _PART_TextBox_GotKeyboardFocus(object sender, KeyboardFocusChangedEventArgs e)
{
_objMouseIncr = null;
(sender as TextBox).Cursor = Cursors.IBeam;
}
The full project is located here: https://github.com/Dirkster99/NumericUpDownLib
Please let me know if I am missing something or if there are additional questions.
I would like to operate a project planned for windows phone to be used in WPF.
Here is the link :
Loading Data when the User Scrolls to the End
By repeating the code , I perceived, that WPF does not know DependencyPropertyListener() in this method :
static void element_Loaded(object sender, RoutedEventArgs e)
{
FrameworkElement element = (FrameworkElement)sender;
element.Loaded -= element_Loaded;
ScrollViewer scrollViewer = FindChildOfType<ScrollViewer>(element);
if (scrollViewer == null)
{
throw new InvalidOperationException("ScrollViewer not found.");
}
var listener = new DependencyPropertyListener();
listener.Changed
+= delegate
{
bool atBottom = scrollViewer.VerticalOffset
>= scrollViewer.ScrollableHeight;
if (atBottom)
{
var atEnd = GetAtEndCommand(element);
if (atEnd != null)
{
atEnd.Execute(null);
}
}
};
Binding binding = new Binding("VerticalOffset") { Source = scrollViewer };
listener.Attach(scrollViewer, binding);
}
Would there be a way around this object ?
You can listen to dependency property value change using a DependencyPropertyDescriptor.
static void element_Loaded(object sender, RoutedEventArgs e)
{
FrameworkElement element = (FrameworkElement)sender;
element.Loaded -= element_Loaded;
ScrollViewer scrollViewer = FindChildOfType<ScrollViewer>(element);
if (scrollViewer == null)
{
throw new InvalidOperationException("ScrollViewer not found.");
}
var dpd = DependencyPropertyDescriptor.FromProperty(ScrollViewer.VerticalOffsetProperty, typeof(ScrollViewer));
dpd.AddValueChanged(scrollViewer, delegate(object o, EventArgs args)
{
bool atBottom = scrollViewer.VerticalOffset
>= scrollViewer.ScrollableHeight;
if (atBottom)
{
var atEnd = GetAtEndCommand(element);
if (atEnd != null)
{
atEnd.Execute(null);
}
}
});
}
Given a point relative to a Page, how do I hittest for a TabControl's tab? VisualTreeHelper.HitTest gives me the contents, but when I go up the visual tree I see nothing that would tell me that I have actually hit a tab. I don't even see the tab control itself.
public class ViewManipulationAgent : IDisposable
{
private const int _limit = 125;
private INavigationService _navigationService;
private FrameworkElement _container;
private FrameworkElement _element;
private TranslateTransform _translate;
private IInputElement _touchTarget;
// When I use this object,
// a_container is the main Frame control in my application.
// a_element is a page within that frame.
public ViewManipulationAgent(FrameworkElement a_container, FrameworkElement a_element)
{
_navigationService = a_navigationService;
_container = a_container;
_element = a_element;
// Since I set IsManipulationEnabled to true all touch commands are suspended
// for all commands on the page (a_element) unless I specifically cancel (see below)
_element.IsManipulationEnabled = true;
_element.PreviewTouchDown += OnElementPreviewTouchDown;
_element.ManipulationStarting += OnElementManipulationStarting;
_element.ManipulationDelta += OnElementManipulationDelta;
_element.ManipulationCompleted += OnElementManipulationCompleted;
_translate = new TranslateTransform(0.0, 0.0);
_element.RenderTransform = _translate;
}
// Since the ManipulationStarting doesn't provide position I capture the position
// here and then hit test elements to find any controls for which I want to bypass
// manipulation.
private void OnElementPreviewTouchDown(object sender, TouchEventArgs e)
{
var position = e.GetTouchPoint(_element).Position;
_touchTarget = null;
HitTestResult result = VisualTreeHelper.HitTest(_element, position);
if (result.VisualHit == null)
return;
var button = VisualTreeHelperEx.FindAncestorByType<ButtonBase>(result.VisualHit) as ButtonBase;
if (button != null)
{
_touchTarget = button;
return;
}
var slider = VisualTreeHelperEx.FindAncestorByType<Slider>(result.VisualHit) as Slider;
if (slider != null)
{
_touchTarget = slider;
return;
}
}
// Here is where I cancel manipulation if a specific touch target was found in the
// above event.
private void OnElementManipulationStarting(object sender, ManipulationStartingEventArgs e)
{
if (_touchTarget != null)
{
e.Cancel(); // <- I have to cancel manipulation or the buttons and other
// controls cannot be manipulated by the touch interface.
return;
}
e.ManipulationContainer = _container;
}
private void OnElementManipulationDelta(object sender, ManipulationDeltaEventArgs e)
{
var element = e.Source as FrameworkElement;
if (element == null)
return;
var translate = _translate.X + e.DeltaManipulation.Translation.X;
if (translate > _limit)
{
GoBack();
translate = _limit;
}
if (translate < -_limit)
{
GoForward();
translate = -_limit;
}
_translate.X = translate;
}
private void GoForward()
{
var navigationService = ServiceLocator.Current.GetInstance<INavigationService>();
navigationService.GoForward();
}
private void GoBack()
{
var navigationService = ServiceLocator.Current.GetInstance<INavigationService>();
navigationService.GoBack();
}
private void OnElementManipulationCompleted(object sender, ManipulationCompletedEventArgs e)
{
_touchTarget = null;
_translate.X = 0;
}
public void Dispose()
{
_element.PreviewTouchDown -= OnElementPreviewTouchDown;
_element.ManipulationStarting -= OnElementManipulationStarting;
_element.ManipulationDelta -= OnElementManipulationDelta;
_element.ManipulationCompleted -= OnElementManipulationCompleted;
}
}