Develop Reference

C# custom control cursor position

I'm making a custom control slider so I can adjust the appearance myself.
However, I can't find a way to get the cursor position relative to the control.
It would propably be easy to code for each control after plopping the controls into my program. But I'd like to have the full functionality inside the custom control project and only having to worry about getting a value from the slider once it's inside my program.
So I need to get the cursor tracking done inside the custom control project.
I've tried using the event here:
private void CustomSlider_MouseDown(object sender, MouseEventArgs e)
{
}
But the only position I'm able to get is the 'global' screen location of the cursor, which will not help me unless I know the position of the control.
I hope my question is clear, thanks.

To obtain the cursor position within the control's event-handler or corresponding virtual method, use the MouseEventArgs.Location(MSDN) property:
class CustomControl : Control {
protected override void OnMouseDown(MouseEventArgs e) {
Point cursorPos = e.Location;
}
}
To obtain the cursor position outside the control, use the Control.MousePosition(MSDN) static property and the PointToClient()(MSDN) method:
CustomControl ctrl = ...
Point cursorPos = ctrl.PointToClient(Control.MousePosition);

get specific image location from PixtureBox inside Panel

I have a PixtureBox inside Panel in c#, and I am trying to get the image location when i click on a certain image location. So I am using mouse location to get x and y, when the mouse is hovering over the image. This works fine if the image size is less than the size of the panel (no sliding bar). As soon as I get an image bigger than the panel size, I will get sliding bar. However, i get the same location if i moved the slide bar down. Is there a better way to get the specific image location with or without the sliding bar? any help is much appreciated :)

The Mouse_Hover event has a default EventArgs so it doesn't send the current mouse position when the event is invoked. The Mouse_Move event does provide the mouse location relative to the scroll position. If you store the location received in an Mouse_Move event from your PictureBox in local variable the Hover event can then use that position.
The position is absolute to the origin of the control so it doesn't matter if the picturebox is scrolled inside a panel.
Point last; // hold the last mousemove location
private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
// store the location in last
last.X = e.Location.X;
last.Y = e.Location.Y;
}
private void pictureBox1_MouseHover(object sender, EventArgs e)
{
// do whatever we want to do with the last location
Trace.WriteLine(last);
}

How to make picturebox change image smooth and fast

I got a picture box that got an original image in my program. When i hover with my mouse over it it changes picture to another picture and when i leave it changes back.
But..
There is such a delay to change to the right picture if i hover over it or not. It takes like 1 second before it changes, What should i change to improve the speed of the change? This is the code i am using at the moment:
private void pictureBox1_MouseHover(object sender, EventArgs e)
{
pictureBox1.Image = ABC_Bok.Properties.Resources.BokVänsterhörn_1;
}
private void pictureBox1_MouseLeave(object sender, EventArgs e)
{
pictureBox1.Image = ABC_Bok.Properties.Resources.BokVänsterhörnet;
}

This is the third time today that I've seen this issue. MouseHover is raised when the mouse pointer STOPS OVER a control. If you want something to happen as soon as the mouse pointer goes over the control then you want MouseEnter, just as you're using MouseLeave for the change back again.

how to detect a mouse click on drawn image?

I am new to c# Windows Form Application Development.
I created a form with a panel in which the user can draw image on it. How do I check if the image is clicked?

In designer mode, right-click on the panel, go to Properties.
In the Properties window, choose EVENTS (Lightning icon).
Double click on Click, then this code will be generated:
private void panel1_Click(object sender, EventArgs e)
{
//--what to do when user clicks on panel--
MessageBox.Show("Clicked");
}

Just double-click on the form's image-panel (or whatever object you wish to detect click events on) and Visual Studio will automatically generate a OnClick() event. Needless to say, I'm talking about the forms designer, not the actual form you will see when testing your code.
Alternatively, you can set which events you want to implement through the object's properties. That way you can also implement OnKeyDown() or OnFocus() or any other kind of events.
Edit: If the image doesn't cover the entire panel, you'll have to check if the mouse position is within the image's dimension. Assuming the image is drawn at position (imgOriginX, imgOriginY) and has the size (imgWidth, imgHeight):
// Fires, when user clicks on panel
private void panel_Click(object sender, EventArgs e)
{
// Cast to MouseEventArgs
MouseEventArgs mouse = (MouseEventArgs)e;
// If mouse is within image
if (mouse.X >= imgOriginX && mouse.Y >= imgOriginY && mouse.X < imgOriginX + imgWidth && mouse.Y < imgOriginY + imgHeight)
{
// do something here
}
}

Double click timer event

I am developing an application that maps users eye movements with the cursor movements, hence developing ahands free cursor control system.
I am using Open CV library's .NET Wrapper for C# i.e. Emgu CV for development.
I am stuck at a point where I want to open a file/folder such that when a cursor is placed over a file/folder for say 3 to 5 seconds, the file/folder should open up or just perform a double-click event of a conventional mouse.
What could I use so as to solve this problem?

Timer timer = new System.Timers.Timer(5000);//5 seconds
timer.Elapsed += new ElapsedEventHandler(timer_Elapsed);
private void form_MouseHover(object sender, System.EventArgs e)
{
timer.Start();
}
private void form_MouseLeave(object sender, System.EventArgs e)
{
timer.Stop();
}
void timer_Elapsed(object sender, ElapsedEventArgs e)
{
timer.Stop();
OpenFileOrFolder();//Edit : implement your file / folder opening logic here
}

I guess you need to break it down:
Detect when the mouse moves or hovers
Send a double click
For 1, I'd be looking at: capturing WM_MOUSEMOVE if you want your own definition of 'hovering'. For example, having a greater threshold for how much movement you'll tolerate and still consider it a 'hover'. Or, you could use the OS defined threshold and look for WM_MOUSEHOVER
For 2, SendInput should get you there
I'm assuming here, you don't actually care what's under the mouse per-se. As in, you're not going to do different behavior depending on what's under the mouse. For example, you'd send the double click when hovering over the titlebar, as well as if you were hovering over the file.
This article on project builds up a Spy++ style app, which should help.

Are you mapping eye control to the mouse pointer? The MouseHover event may be useful:
http://msdn.microsoft.com/en-us/library/system.windows.forms.control.mousehover.aspx
As well as MouseEnter, MouseLeave, etc.
If you're controlling a separate element (i.e., not the mouse) with the eyes, then I had to do something similar in WPF. It ultimately came down to mapping control coordinates to mouse location, counting the time within the bounds of that control, then calling the mouse click event handler.