Develop Reference

How to change cursor on disabled buttons in C#

I just started working on C# with Visual Studio & Windows Forms Applications. I was trying to create a Calculator and I was wondering if I could change the cursor type on a button which is disabled, I can't figure out how to do it, please help me thank you!
Edit: here's the code I tried to do, it only works if the button's enabled...
private void txt_current_operation_MouseHover(object sender,EventArgs e) {
txt_current_operation.Cursor=Cursors.Hand;
}

Hack Answer
Assuming the Button is contained by the Form, you can handle the MouseMove event of the Form and change the cursor from there:
private void Form1_MouseMove(object sender, MouseEventArgs e)
{
Rectangle rc = txt_current_operation.RectangleToScreen(txt_current_operation.ClientRectangle);
this.Cursor = rc.Contains(Cursor.Position) ? Cursors.Hand : Cursors.Default;
}
If the Button was contained by a Panel, or some other container besides the Form, then you'd change to the MouseMove event of that container instead.
Demonstration:

How to hide control when click outside it?

I have a WindowForm and some controls on it.
My point is that when I click button "?" on top-right of the datagridview, it will show a picture box and when I click outside the pictureBox, it must invisible.
My MainForm
MyPictureBox
I have searched some topics on this site, but some dont work, some work partly. Like
this.
I also tried:
void pictureBox1_LostFocus(object sender, EventArgs e)
{
if (pictureBox1.Visible)
pictureBox1.Visible = false;
}
But when I click on button2, button3, ... The pictureBox wasn't invisible.
Any solution will be highly appreciated.

I think your pictureBox1 isn't losing focus, cause it never actually GOT focused. Set it to be focused after making it visible.

Oh, I have encountered this before...
I was making a Label that you could double click and it would allow you to edit the Label.Text, like a TextBox. However, I was having problems hooking into the events to know when the user had clicked off the Control and wished to stop editing. I tried Control.LostFocus, and Control.Leave, but nothing. I even got frustrated/desperate and tried some silly ones like Control.Invalidated.
What I ended up having to do was subscribe to the Click event of the Form/Container/Control behind it.
However, putting the responsibility of wiring up this event into the Form that wants to use it is poor design. What you can do, however is to make the constructor to Control class require a reference to the owner/parent/container as a parameter. That way, the requirements are not hidden, they must be satisfied before you can get a object instance, and the control can wired up to the Form.Click within itself, where that logic belongs.
private Form owner;
public EditLabel(Form Owner)
{
this.owner = Owner;
owner.Click += EndEditing;
}

Add this method in designer.cs:
pictureBoxEvent this.MouseLeave += new EventHandler(pictureBox_MouseLeave);
Add this code in cs file:
private void pictureBox_MouseLeave(object sender, EventArgs e)
{
pictureBox1.Visible = false;
}

In Windows Forms, is there a control that shows a text overlay like a tooltip without all the tooltip behavior?

I just want some kind of simple text overlay that shows for a few seconds when I tell it to, at a certain location, just like the normal tooltip.
However, I don't want the normal tooltip behavior of automatically showing when the mouse hovers over the control it's associated with. Can I disable this behavior on the normal tooltip, or is there some other control I can use?

You can just call the tooltip yourself:
private void button1_Click(object sender, EventArgs e)
{
ToolTip tip = new ToolTip();
tip.ToolTipTitle = "Title";
tip.Show("Hello", button1, 10, button1.Height - 6, 5000);
}

Scrolling problem with a WebBrowser control contained in a Panel control

I have a .Net Panel control that contains a single child control that is a WebBrowser. I won't go into the reasons for me doing that, but it is related to printing out the control. The panel control has its AutoScroll property set to "true" and I am sizing the WebBrowser to fit its own content (by using the .Document.Body.ScrollRectangle.Size property of the WebBrowser when the NavigateComplete2 event fires). In this way, the scrollbar on the panel appears and you can scroll the panel up and down in order to be able to see the content of the WebBrowser.
The problem is that when you scroll down to see what's at the bottom of the WebBrowser and then click on it (perhaps you click on a link in the html), the panel jumps back to the top and the link doesn't get actioned.
Please can anyone help me to understand what's going on and how to get around this problem?

I had the same problem, also with a WebBrowser inside a Panel. Here's the solution I'm using (which I found somewhere else on stackoverflow):
class AutoScrollPanel : Panel
{
public AutoScrollPanel()
{
Enter += PanelNoScrollOnFocus_Enter;
Leave += PanelNoScrollOnFocus_Leave;
}
private System.Drawing.Point scrollLocation;
void PanelNoScrollOnFocus_Enter(object sender, System.EventArgs e)
{
// Set the scroll location back when the control regains focus.
HorizontalScroll.Value = scrollLocation.X;
VerticalScroll.Value = scrollLocation.Y;
}
void PanelNoScrollOnFocus_Leave(object sender, System.EventArgs e)
{
// Remember the scroll location when the control loses focus.
scrollLocation.X = HorizontalScroll.Value;
scrollLocation.Y = VerticalScroll.Value;
}
protected override System.Drawing.Point ScrollToControl(Control activeControl)
{
// When the user clicks on the webbrowser, .NET tries to scroll to
// the control. Since it's the only control in the panel it will
// scroll up. This little hack prevents that.
return DisplayRectangle.Location;
}
}

try setting TabStop to false on both the containing panel as well as the WebBrowser control. That did the trick for me. The reason this works is that if it's set as a wanting to be a tabstop, it will take the first click event to mean that it's receiving focus. This then resets the scroll bar positions... not sure why it does that...
However, on navigating to a new page you'll need to manually reset the scroll bar positions...
Here is what I used. Yeah it's a hack.
private void webBrowser1_Navigating(object sender, WebBrowserNavigatingEventArgs e)
{
webBrowser1.TabStop = true;
webBrowser1.Focus();
webBrowser1.TabStop = false;
}

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);
}
}