Is there an event in WinForms that get's fired when a window is dragged?
Or is there a better way of doing what I want: to drop the window opacity to 80% when the window is being dragged around?
Unfortunately this is stupidly tricky to search for because everyone is looking for drag and drop from the shell, or some other object.
No need for WndProc hacking, this works fine:
protected override void OnResizeBegin(EventArgs e) {
this.Opacity = 0.6;
}
protected override void OnResizeEnd(EventArgs e) {
this.Opacity = 1.0;
}
Moves also trigger the OnResizeXxx events.
It's the LocationChanged event you want:
private void YourApp_LocationChanged(object sender, EventArgs e)
{
this.Opacity = 0.8;
}
You'll have to override WndProc and handle the exit move event to reset the opacity back to 1:
protected override void WndProc(ref Message m)
{
Trace.WriteLine(m.ToString());
switch (m.Msg)
{
case WMEXITSIZEMOVE:
this.Opacity = 1.0;
break;
}
base.WndProc(ref m);
}
Not forgetting to define the message code:
private const int WMEXITSIZEMOVE = 0x0232;
It might be more efficient to handle the WM_ENTERSIZEMOVE (code 0x0231) message instead of LocationChanged as this would only result in setting the opacity once (at the start of the drag) rather than continually throughout the drag.
Related
I have a WPF ItemsControl displaying a series of Rectangles.
Each rectangle makes use of MVVM Lights EventToCommand to track the MouseEnter event and set the Rectangle to 'Selected'
I then use this property to highlight the rectangle using triggers in the style.
My problem occurs if the mouse is dragged too quickly.
Working (Slowly dragged):
Not working (quickly dragged):
In this case the event has not fired for the second Rectangle.
How do I make sure the event fires for all controls the mouse moves over?
My suggestion would be to put all the event occurences in a queue. I think your problem occures because when an event fires, you call one method and if the method hasn't finished at the time the next event occurs, it can not be called a second time.
Create a queue and put the event occures in there, then create a thread that waits for the queue to fill and then procceses it it.
Sample:
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace ConsoleApplication3
{
using System.Timers;
using Timer = System.Timers.Timer;
class Program
{
private static Queue<My_Event> EventQueue;
private static Timer t = new Timer(10);
static void Main(string[] args)
{
Task thread = new Task(MarkStuffYellow);
EventQueue = new Queue<My_Event>();
t.Elapsed += t_Elapsed;
t.Start();
t.AutoReset = true;
}
static void t_Elapsed(object sender, ElapsedEventArgs e)
{
EventQueue.Enqueue(new My_Event(sender, e));
}
private static void MarkStuffYellow()
{
/// !!! While (true) is not an solution, if you do it like this,
/// your CPU will be full !!!
while (true)
{
if (EventQueue.Any())
{
My_Event myEvent = EventQueue.Dequeue();
var sender = myEvent.Sender;
var e = myEvent.E;
/// Do Stuff with your event
}
}
}
}
/// Needed to save your event
internal class My_Event
{
public My_Event(object sender, ElapsedEventArgs e)
{
this.Sender = sender;
this.E = e;
}
public object Sender;
public ElapsedEventArgs E;
}
}
I haven't used Unity 3D but I gather you can use Screen.lockCursor to take control of the mouse for FPS games. Is this possible in WPF/Win32?
Obviously you have to release it when exiting or in the event of a crash
Thanks
I found the answer spread across a whole bunch of links, so
(1) Set a captureMouse flag, press once to go into this mode, again to come out,
hide the cursor while you are in there
bool captureMouse = false;
private void viewport3D1_MouseDown(object sender, MouseButtonEventArgs e)
{
if (!captureMouse)
{
captureMouse = true;
Mouse.OverrideCursor = Cursors.None;
}
else
{
Mouse.OverrideCursor = null;
captureMouse = false;
}
}
(2) While you're in this mode constantly put the mouse back to the middle of the window
private void theWindow_MouseMove(object sender, MouseEventArgs e)
{
if (!captureMouse)
return;
Point windowPoint = WpfToRealPixels(theWindow, new Point(500, 500));
NativeMethods.SetCursorPos((int)windowPoint.X, (int)windowPoint.Y);
oldP = new Point(500, 500);
}
(3) Translate the co-ords
private Point WpfToRealPixels(Window w, Point p)
{
return theWindow.PointToScreen(p);
}
(4) To put the mouse back you'll need a native Win32 call
public partial class NativeMethods
{
[System.Runtime.InteropServices.DllImportAttribute("user32.dll", EntryPoint = "SetCursorPos")]
[return: System.Runtime.InteropServices.MarshalAsAttribute(System.Runtime.InteropServices.UnmanagedType.Bool)]
public static extern bool SetCursorPos(int X, int Y);
}
Hope that helps someone.
How do I go about implementing the drag delta on a Shape, I have the following code:
void Connector_MouseLeftButtonDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
if (e.ClickCount == 1)
{
this.Focus();
this.CaptureMouse();
this.RaiseEvent(new DragStartedEventArgs(0,0));
initMousePoint = e.GetPosition(this);
}
e.Handled = true;
}
void Shape2_MouseMove(object sender, System.Windows.Input.MouseEventArgs e)
{
currMousePoint = e.GetPosition(this);
if (this.IsMouseCaptured)
{
this.RaiseEvent(new DragDeltaEventArgs(0,0);
}
}
void Shape2_MouseLeftButtonUp(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
this.ReleaseMouseCapture();
}
Now for the DragDeltaEvent args do I need to compute the drag in the mousemove and pass it to the event, also is this the right way to raise the event. If this works, then I should only subscribe to the drag delta event and use it as a thumb? Note, I do not want to template the thumb with the shape, providing this answer won't help me.
note the chagnes, about the getting the position of the mouse, this I don't think works, because it gets the position relative to the element, not the containing panel, so I don't think i will be able to find the drag distance this way.
I solved it using:
currMousePoint = e.GetPosition(this);
double dragHorizontal = currMousePoint.X - initMousePoint.X;
double dragVertical = currMousePoint.Y - initMousePoint.Y;
//Set the new canvas top and left proeprties here.
I have a control that is similar to a Popup or Menu. I want to display it and when the user clicks outside the bounds of the box, have it hide itself. I've used Mouse.Capture(this, CaptureMode.SubTree) as well as re-acquired the capture the same way Menu/Popup do in OnLostMouseCapture.
When the user clicks outside the bounds of the control, I release the mouse capture in OnPreviewMouseDown. I don't set e.Handled to true. The mouse click will make it to other controls on the main UI, but not to the close button (Red X) for the window. It requires 2 clicks to close the app.
Is there a way to tell WPF to restart the mouse click, or to send a repeated mouse click event?
Here's my code. Note I renamed it to MainMenuControl - I'm not building a Menu, so Menu/MenuItem and Popup aren't options.
public class MainMenuControl : Control
{
static MainMenuControl()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(MainMenuControl), new FrameworkPropertyMetadata(typeof(MainMenuControl)));
}
public MainMenuControl()
{
this.Loaded += new RoutedEventHandler(MainMenuControl_Loaded);
Mouse.AddPreviewMouseDownOutsideCapturedElementHandler(this, OnPreviewMouseDownOutsideCapturedElementHandler);
}
void MainMenuControl_Loaded(object sender, RoutedEventArgs e)
{
this.IsVisibleChanged += new DependencyPropertyChangedEventHandler(MainMenuControl_IsVisibleChanged);
}
void MainMenuControl_IsVisibleChanged(object sender, DependencyPropertyChangedEventArgs e)
{
if (this.IsVisible)
{
Mouse.Capture(this, CaptureMode.SubTree);
Debug.WriteLine("Mouse.Capture");
}
}
// I was doing this in OnPreviewMouseDown, but changing to this didn't have any effect
private void OnPreviewMouseDownOutsideCapturedElementHandler(object sender, MouseButtonEventArgs e)
{
Debug.WriteLine("OnPreviewMouseDownOutsideCapturedElementHandler");
if (!this.IsMouseInBounds())
{
if (Mouse.Captured == this)
{
Mouse.Capture(this, CaptureMode.None);
Debug.WriteLine("Mouse.Capture released");
}
Debug.WriteLine("Close Menu");
}
}
protected override void OnLostMouseCapture(MouseEventArgs e)
{
base.OnLostMouseCapture(e);
Debug.WriteLine("OnLostMouseCapture");
MainMenuControl reference = e.Source as MainMenuControl;
if (Mouse.Captured != reference)
{
if (e.OriginalSource == reference)
{
if ((Mouse.Captured == null) || (!reference.IsAncestorOf(Mouse.Captured as DependencyObject)))
{
//TODO: Close
Debug.WriteLine("Close Menu");
}
}
// if a child caused use to lose the capture, then recapture.
else if (reference.IsAncestorOf(e.OriginalSource as DependencyObject))
{
if (Mouse.Captured == null)
{
Mouse.Capture(reference, CaptureMode.SubTree);
Debug.WriteLine("Mouse.Capture");
e.Handled = true;
}
}
else
{
//TODO: Close
Debug.WriteLine("Close Menu");
}
}
}
private bool IsMouseInBounds()
{
Point point = Mouse.GetPosition(this);
Rect bounds = new Rect(0, 0, this.Width, this.Height);
return bounds.Contains(point);
}
}
The problem is that the mouse handling you are talking about is outside the WPF eventing system and part of the operating system so we're really talking about two fairly different mouse message queues that interact well enough most of the time but in these edge case we see that the interoperability is not perfect.
You could try to generate Win32 mouse messages or send your own window a close message but all those approaches are hacks. Since popups and menus exhibit exactly the same symptoms you describe, it doesn't seem like there is going to be an easy to way to accomplish what you want as you've described it.
Instead, I suggest that you consider giving up the mouse capture when the mouse leaves the north client area of the window or some other heuristic such as a specified distance from the control. I know this is probably not ideal but it might be a satisfactory compromise if you want the close button to work badly enough.
In a .NET CF-form i have multiple panels. I want to have a property that should always be informed about if a panel is in the front.
Can this be done using the GetChildIndex() method?
If yes, how do i intercept the change to SetChildIndex()?
Thanks in advance
For everybody who is interested for future use:
simply add a new event handler for the Paint event of each panel, for example:
panel1.Paint += new PaintEventHandler(panel1_Paint);
panel2.Paint += new PaintEventHandler(panel2_Paint);
and in each of the event handlers just call a Method which retrieves the state of all the panels like so:
void panel2_Paint(object sender, PaintEventArgs e)
{
GetPanelStates();
}
void panel1_Paint(object sender, PaintEventArgs e)
{
GetPanelStates();
}
void GetPanelStates()
{
Panel2IsInFront = panel2.Parent.Controls.GetChildIndex(panel2) == 0;
Panel1IsInFront = panel1.Parent.Controls.GetChildIndex(panel1) == 0;
}