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stopping event from code C#, call event by user not by code

Sorry, this may be a duplicate question, but I couldnot understand the solutions already provided in different answers.
I have created a mp3 player in a different manner, it plays one mp3 file at a time but one listbox have the chapters, which is not only handling to move position of that particular mp3 but also changes a picturebox image. Now somewhere I need to change the selection of the listbox from a seekbar but dont want to fire the following event of;
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
Please guide.

One way to inhibit your selection indexed change event doing its normal way is to use a boolean flag. Also, make sure that this inhibition does not stay around when some exception is raised:
private bool inhibit = true;
private void doSomeProcessWithInhibit()
{
try
{
inhibit = true;
// processing comes here
}
// if something goes wrong, make sure other functionality is not blocked
finally
{
inhibit = false;
}
}
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
// fast return to reduce nesting
if (inhibit)
return;
// do event handling stuff here
}
P.S. Try to use meaningful names for controls (check listBox1). You will thank yourself when revisiting the code and/or others have to.

Add a Boolean with class scope called something like isProcessing. Set it to true. Do your work, then set it to false. Warp your event in the Boolean:
bool isProcessing = true;
private void switchControls(){
isProcessing = true;
//do work;
isProcessing = false;
}
private void MyControl.OnEvent(object sender, EventArgs e){
if(!isProcessing){
//what you would normally do
}
}
OR....
Deregister the event, the re-register it
private void switchControls(){
myButton1.OnClick -= myButtonClick;
//do work
myButton1.OnClick += myButtonClick;
}

How to get the mouse coordinate inside an OpenTK.GLControl?

I have a program that uses OpenTk.GLControl. Now on my listener, every time the mouse hovers to the said control, say "glControl1", I want to get the mouse coordinates.
Is that possible? sample code below.
private void glControl1_MouseHover(object sender, EventArgs e)
{
// get the current mouse coordinates
// .........
}

OpenTK.GLControl inherits from System.Windows.Forms.Control. You can use the following code snippet to get the mouse position:
private void glControl1_MouseHover(object sender, EventArgs e)
{
Control control = sender as Control;
Point pt = control.PointToClient(Control.MousePosition);
}
Please refer to the MSDN WinForms documentation for more information.

The problem is that you're using the wrong event. Many UI actions in WinForms trigger multiple events per action; Hover is used for things like popping up tooltips. You don't get a coordinate in Hover because it's unnecessary.
What you want is the MouseMove event. This is used to track the mouse position:
private void glControl1_MouseMove(object sender, MouseEventArgs e)
{
foo = e.X;
bar = e.Y;
}

I dont know, what is OpenTk.GLControl, but:
I was handling swipe events on Windows Phone and did this:
private void PhoneApplicationPage_MouseLeftButtonDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
//string to save coordinates of tap
TapCoordinatesXBegin = e.GetPosition(LayoutRoot).X.ToString();
TapCoordinatesYBegin = e.GetPosition(LayoutRoot).Y.ToString();
}
And i dont remember such event MouseHover - maybe MouseEnter?

Mouse up event doesn't get triggered

I have the following problem: I have a panel which has a specific color, say red.
When the user presses his mouse, the color of this panel gets stored in a variable. Then the user moves, his mouse still pressed, over to another panel. When he releases the mouse there, this panel should get the background color of the first that had been stored in the variable. My code looks something like this:
public Color currentColor;
private void ColorPickMouseDown(object sender, MouseEventArgs e)
{
Panel pnlSender = (Panel)sender;
currentColor = pnlSender.BackColor;
}
private void AttempsColorChanger(object sender, MouseEventArgs e)
{
Panel pnl = (Panel)sender;
pnl.BackColor = currentColor;
}
I need to identify the sender first because there are many possible panels that can trigger this event. The first MouseDown method works totally fine, the color is stored nicely in the variable. The secon one however doesn't even get triggered when the user does what I described above. When the ser clicks on the second panel, it works (there is an MouseUp part in a click aswell I guess).
What's wrong here? Why is the event not triggered when the user holds the mouse key down before?

(This answer assumes you are using Windows Forms.)
It could be that you need to capture the mouse by setting this.Capture = true in the MouseDown of the source control. (See Control.Capture)
If you did that, the source window would get the MouseUp event, and it would be the source window that had to determine the destination window under the mouse coords. You can do that using Control.GetChildAtPoint() (see this answer on Stack Overflow).
Use Windows Forms Drag and Drop Support Instead! <- Click for more info
I'm going to suggest you bite the bullet and use the .Net Drag and Drop methods to do this. It requires some reading up, but it will be much better to use it.
You start a drag in response to a MouseDown event by calling Control.DoDragDrop().
Then you need to handle the Control.DragDrop event in the drop target control.
There's a few more things you might need to do to set it up; see the Control.DoDragDrop() documentation for an example.
(For WPF drag and drop support, see here.)

when your mouse enter the target control , mouse down triggerd ang get target BackColor! you need add an boolean flag to your code :
public Color currentColor;
bool flag=false;
private void ColorPickMouseDown(object sender, MouseEventArgs e)
{
if(flag==false)
{
flag=true
Panel pnlSender = (Panel)sender;
currentColor = pnlSender.BackColor;
}
}
//assume mouse up for panles
private void AttempsColorChanger(object sender, MouseEventArgs e)
{
if(flag==true)
{
Panel pnl = (Panel)sender;
pnl.BackColor = currentColor;
flag=flase;
}
}
and also you need change your flag in mouseMove( if )

As I mentioned in my comment Mouse Events are captured by the originating control, You would probably be better off using the DragDrop functionality built into Windows Forms. Something like this should work for you. I assigned common event handlers, so they can be assigned to all of your panels and just work.
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void panel_MouseDown(object sender, MouseEventArgs e)
{
((Control)sender).DoDragDrop(((Control)sender).BackColor,DragDropEffects.All);
}
private void panel_DragDrop(object sender, DragEventArgs e)
{
((Control)sender).BackColor = (Color)e.Data.GetData(BackColor.GetType());
}
private void panel_DragEnter(object sender, DragEventArgs e)
{
e.Effect = DragDropEffects.Copy;
}
}

I know it's an old question but I had the same issue and none of the above answers worked for me. In my case I had to handle the MouseMove event in the target control and check for the mouse to be released. I did set 'BringToFront' on my target panel just in case that helped at all.
public Color currentColor;
private void ColorPickMouseDown(object sender, MouseEventArgs e)
{
Panel pnlSender = (Panel)sender;
currentColor = pnlSender.BackColor;
}
private void panelTarget_MouseMove(object sender, MouseEventArgs e)
{
//the mouse button is released
if (SortMouseLocation == Point.Empty)
{
Panel pnl = (Panel)sender;
pnl.BackColor = currentColor;
}
}

Is there a way to set a control as a tooltip?

I'm wondering if it's possible to use ToolTip.SetToolTip or something similar to open a control as a tooltip instead of just a string (i.e. SetToolTip(controlToWhichToAdd, panelToDisplayAsToolTip) instead of passing a string as your second parameter).
If this isn't possible I'm guessing next best thing is displaying a panel on the mouse location on mouse_enter event on the control and removing it (or making it invisible) on mouse_leave.
Or are there other practices that make this possible in an easier way?

This is not possible out of the box. You have two choices. First option is to override the Draw Event, which will let you customize how the tooltip looks. Here is an example of this. Be sure you set the OwnerDraw property to true if you use this method!
Although the first method will work if you just need some simple customization, the second option will work best if you need more flexible options. The second option is to do what you already suggested and create your own sort of tooltip. Simply put, you would first create an event handler for the MouseEnter event. When that event fires, you'd enable a Timer. This timer would be the delay that occurs before the tooltip is show. Then finally, you'd just make your panel appear at the mouse coordinates.
Suppose you have a form with a button and timer on it and you want the button to have a tooltip that is a panel:
public partial class Form1 : Form
{
private Panel _myToolTipPanel;
private void Form1_Load(object sender, EventArgs e)
{
_myToolTipPanel = new Panel {Visible = false};
Controls.Add(_myToolTipPanel);
Label myLabel = new Label();
myLabel.Text = "Testing";
_myToolTipPanel.Controls.Add(myLabel);
}
private void button1_MouseEnter(object sender, EventArgs e)
{
timer1.Enabled = true;
}
private void button1_MouseLeave(object sender, EventArgs e)
{
timer1.Enabled = false;
_myToolTipPanel.Visible = false;
}
private void timer1_Tick(object sender, EventArgs e)
{
timer1.Enabled = false;
Point position = Cursor.Position;
Point formPoisition = PointToClient(position);
_myToolTipPanel.Visible = true;
_myToolTipPanel.Location = formPoisition;
}
}
Now of course you will have to do some beautifying of the tooltip, but this is the general idea!

One Approach could be inheriting the ToolTip control and then override the SetToolTip and Show methods . Inside the SetToolTip the private method - SetToolTipInternal needs to be re-written , but most of the functionality could be reuse - it uses the Mouse Events ( leave , move) to bind region. but since tooltip uses internal's of windows to show the baloon window. you will have to override quite a bit of code.
but this could be time consuming and needs quite a bit of testing.

You could write a handler for the Tooltip.Popup event, and cancel the popup to display your own panel.
You'd need to clean it up at the appropriate time, though.
For example:
private void ToolTip1_Popup(Object sender, PopupEventArgs e)
{
e.Cancel = true;
//Do work here to display whatever control you'd like
}
If you're just looking for more formatting options in the tooltip display, an alternative is something like this CodeProject entry, which implements an HTML-enabled tooltip:

Cursor keeps resetting to default unless I set it on MouseMove

Have a simple form that has a PictureBox in one location. I want to change the cursor to the Cross cursor when entering that control, and change it back when it leaves.
private void Canvas_MouseEnter(object sender, EventArgs e)
{
this.Canvas.Cursor = Cursors.Cross;
}
private void Canvas_MouseLeave(object sender, EventArgs e)
{
this.Canvas.Cursor = Cursors.Default;
}
This doesn't work. If I look closely, I can see it quickly change on MouseEnter, but it flips right back to the default cursor. I have to add "this.Canvas.Cursor = Cursors.Cross;" to the MouseMove event in order for it to work, but then I can constantly see it flickering back to the default cursor.
What gives? This is the only cursor-related code in my whole application, what would be causing it to reset to the default cursor every time I move the mouse?
Thanks.
EDIT: I am an idiot. Person I am collaborating with on this little app had some cursor code tucked away somewhere else that was causing the problem. Thanks guys.

Why don't you set the cursor for the picturebox?
yourPictureBox.Cursor = Cursors.Cross;

I've tried in a new project from scratch (with just the mouseenter/leave handlers and nothing else) and it works.
Might be something else in your application ?

public Form1()
{
InitializeComponent();
pictureBox1.MouseHover += new EventHandler(PictureBox1_MouseHover);
}
void pictureBox1_MouseHover(object sender, EventArgs e)
{
this.PictureBox1.Cursor = Cursors.Cross;
}
You want to use MouseHover event handler.