Develop Reference

Changing visiblity screwing up events in C#?

I have setup a Panel that has a number of Buttons on it. These Buttons Visible Property is set to false. When I move the mouse over the Panel they became Visible and when I move the mouse out of the Panel they once again became invisible. This all works fine.
The code to do this is:
private void _Display_MouseEnter(object sender, EventArgs e)
{
foreach (Control C in _Display.Controls)
{
C.Visible = true;
}
}
private void _Display_MouseLeave(object sender, EventArgs e)
{
foreach (Control C in _Display.Controls)
{
C.Visible = false;
}
}
The problem is the Events I have set for the Buttons seem to get removed by doing this. If I don't change the Buttons visiblity the events fire as normal. I have set the events in the Designer.
Am I missing something or is this how its supposed to work and I have to resubscribe my events each time I change the Buttons visiblity?
Thanks
Danny

I did some research on that and apparently when the cursor enters one of the buttons the Panel's MouseEnter and MouseLeave events fire until the cursor leaves that button so what it does is not allowing your buttons to catch the Click event.
I think the best solution would be to get the cursor position and check if it is within your panel and then set your buttons visibility.

Button clicked event not triggering after lost focus event

I have a Winforms c# form with some comboBoxes , cancel and save buttons that work fine.
I now need to capture when the user has finished entering text into a comboBox.
I add an empty ( for now) lostFocus (or Leave) event to the combbox , which triggers fine. However if the cause of that event was a cancel or save button press , the corresponding event is no longer triggered. These buttons still work fine if pressed at other times.
Should these two event be firing in sequence or is there some better way to capture completed text entry?

The Leave and/or LoseFocus events do not get triggered because you do not leave the combobox and because it doesn't lose focus when you press Enter or Escape.
Therefore the best way is to add the function you are triggering in the LoseFocus event, also to the Button click events of the Cancel- and the Accept-Buttons.
Adding a call to the leave event itself: comboBox1.Leave(null, null); would be the simplest way.
To make sure that the function is called only once, I check who has focus in the ButtonClick events:
private void acceptButton_Click(object sender, EventArgs e)
{
if (comboBox1.ContainsFocus) comboBox1_Leave(acceptButton, null);
// do accept stuff here..
}
private void cancelButton_Click(object sender, EventArgs e)
{
if (comboBox1.ContainsFocus) comboBox1_Leave(cancelButton, null);
// do cancel stuff here..
}
private void comboBox1_Leave(object sender, EventArgs e)
{
// do leave stuff here..
Console.WriteLine(sender);
}
I also pass in the Button so you could check the sender to see how the Leave was triggered..

I'm answering my own question here as I feel it might be useful to other newbies.
The breakpoint I had set in my empty lostFocus event was stopping button click event from occurring. When I removed the breakpoint the problem went away.
However when I added code to my lostFocus event, a form redraw was sometimes moving the buttons and preventing their events from firing. To solve this problem I adapted TaWs very useful answer and fired the button event from within the lostFocus event.
private void comboBox1_LostFocus(object sender, EventArgs e)
{
bool saving = btnSave.ContainsFocus;
// form redraw stuff here..
if (saving)
btnSave_Click(btnSave, null);
}

MouseLeave not fired C# WinForms

I have a user control with 2 buttons, that should only be visible when the mouse is inside the area of the control.
I'm showing the buttons like this:
private void Node_MouseEnter(object sender, EventArgs e)
{
btn1.Show();
btn2.Show();
}
And hiding like this:
protected override void OnMouseLeave(EventArgs e)
{
if (this.ClientRectangle.Contains(this.PointToClient(Control.MousePosition)))
return;
else base.OnMouseLeave(e);
}
private void Node_MouseLeave(object sender, EventArgs e)
{
btn1.Hide();
btn2.Hide();
}
The problem is that sometimes (random situations) the MouseLeave event is not fired, and the buttons stay visible, even with the mouse outside the control.
Is it possible that multiple events get in conflict ?

As this link states:
Mouse move messages are not accurate enough, they don't guarantee that every traversed pixel is reported. When you have a child window close to the edge of its parent, it is quite easy to not get the MouseEnter for the parent when you move the mouse fast enough.
So, the solution was to listen only for the MouseEnterevent, and when this event is fired, i send a notification to the other controls, to hide its buttons.
Is not the most elegant solution, but it works as expected.

ToolStripButton "Reset Appearance" / "Fire Leave Event"

I have a ToolStripButton that performs an action. The user clicks the button and the button is disabled to prevent the action being performed twice. After the action is complete the button is re-enabled. It all works perfectly...except:
Because the button is disabled it does not fire the "MouseLeave" event and as a result the appearance of the button is not updated. To be absolutely clear, when the mouse enters a ToolStripButton the button is highlighted in orange (by default) with a black box around it. This highlight is not being removed when I re-enable the button. The mouse cursor is, by this time, long gone from the control. Mousing over the button naturally fixes the button by redrawing it.
What I would like to do would be some method on the ToolStripButton that "resets" its appearance. Such a method may even exist on the ToolStrip, but despite searching I have been unable to find anything like this.
As an alternative I could fire the "Mouse Leave" event on the button directly. As far as I know there is no way to easily do this in C# .NET.
Any advice at this point in time would be most appreciated, naturally I don't want to tear up my application and replace the tool strip.

Update:
I reproduced your problem, trying figuring out!
I didn't get a better way other than reset the style in the click event
private void toolStripButton1_Click(object sender, EventArgs e)
{
toolStripButton1.BackColor = Color.FromKnownColor(KnownColor.Control);
toolStripButton1.Enabled = false;
}
private void toolStripButton1_MouseEnter(object sender, EventArgs e)
{
toolStripButton1.BackColor = Color.Red;
}
private void toolStripButton1_MouseLeave(object sender, EventArgs e)
{
toolStripButton1.BackColor = Color.FromKnownColor(KnownColor.Control);
}
Hope this helps!
Have you tried Control.Invalidate()?
from MSDN: Invalidates the entire surface of the control and causes the control to be redrawn.

I had the same problem. I "fixed" it by hiding and then showing back the ToolStripButton using the Visible property after the task was complete.

Before disabling ToolStrip or ToolStripItem:
private void RemoveHighlightFromToolStrip(ToolStrip toolStrip)
{
foreach (ToolStripItem item in toolStrip.Items)
{
if (item.Pressed || item.Selected)
{
item.Visible = false;
item.Visible = true;
}
}
}
also you can just hide and show entire ToolStrip, but this may affect other controls in your form (i.e. if you have some docked DataGridView it would be redrawn)

Tooltip not displaying, flashes when control is clicked

I have a check box that is disabled that should be showing a tooltip when hovered over, but instead nothing happens. Once the checkbox is clicked on the tooltip shows momentarily then flashes on and off very fast. What could be causing this?
The tooltip should also be showing for every control involved, but shows for some and not others eventhough the tooltip is explicitly set for all controls. What could be causing this behavior?
Here is the event handler:
this.MouseHover += new EventHandler(OrderSummaryDetails_MouseHover);
void EventHandler_MouseHover(object sender, EventArgs e)
{
if (someCondition)
{
this.mFormTips.Show("Please open order form to manually modify this order", this);
}
}

I can't be positive, but if using WinForms, and you have your checkbox disabled (as in not enabled), then the checkbox will not receive events. This will cause tooltips not to show up properly.
I had the exact same problem before with a image button and what I ended up having to do was to create a gray scale of the image and swap it out when I wanted the button to be "disabled". I had to add the tooltip to the button and the image (two separate UI elements) and swap out the UI elements.

I added a MouseMove event and applied it to all the controls.
void OrderSummaryDetails_MouseMove(object sender, MouseEventArgs e)
{
Control control = GetChildAtPoint(e.Location);
if (control != null)
{
string toolTipString = mFormTips.GetToolTip(control);
this.mFormTips.ShowAlways = true;
// trigger the tooltip with no delay and some basic positioning just to give you an idea
mFormTips.Show(toolTipString, control, control.Width / 2, control.Height / 2);
}
}