I have a custom control created, comprised of a bunch of text boxes, 1 button and radio buttons.
I then have a "parent" control which only has this 1 custom control placed on it, and in the code behind I have a reference to this control's Presenter.
The presenter handles the actual code for searching (when the one button is pressed). How do I set up the button click event on the child control to call the Search method from the presenter?
So I have the following:
CtlSearchDetails
ViewSearchScreen
PresenterSearchScreen
The button click event is on CtlSearchDetails and it needs to call the method on PresenterSearchScreen. I cannot figure out how to reveal this method to the instace of the control on ViewSearchScreen.
In your custom child control, you want to expose an event for the button click:
public event Action OnButtonClicked;
Then hook the button clicked event from the designer
private void btn_myButton_Clicked(object sender, EventArgs e)
{
if (OnButtonClicked != null)
OnButtonClicked();
}
Then in your parent container, you want to handle this event from the child control
this.myChildControl.OnButtonClicked += new Action(onChildButtonClicked);
private void onChildButtonClicked()
{
// Do your search here
}
I'm using User Controls in C# winforms, and I would like some code to be executed after the load event, and after the control has been shown. If no such event exists, is it possible to make one?
You could use one of events from this list. OnPaint would be most likely candidate.
Form Events:
Construtor
Load
Layout
Activated
Paint
Closing
Closed
Deactivate
Dispose
and for Controls:
Enter
GotFocus
Leave
Validating
Validated
LostFocus
If you can't find one that fits you needs, this article explains how to construct and fire event.
Create a public method in user control
Call the method on Parent win-form Shown Event
This will call the code you want to run once.
You can also use user-control paint event, but this will Expensive call. Because your code will execute every time the control is redrawn.
So it is better to use a flag which you can determine whether to run the code or not
i.e.
private bool _run =true;
private void Control_Paint(object sender, PaintEventArgs e)
{
if(!_run) return;
//call the code you need to run
_run = false;
}
I'm new to windows forms programming so my question may sound little strange.
I have created a user define control (countdown timer) now I'm creating n no of it dynamically in a form by Click of a button (Add new timer) its working well and good.
Here is the Creation Code
private void Addnew_Click(object sender, EventArgs e)
{
UserControl1.userControl11 = new UserControl1();
flowLayoutPanel1.Controls.Add(userControl11);
}
My user control has a Reset button that reset all the content inside the user define control.
it is also working, but What I want Allow user to reset all the Created timers using the “Reset All” button on the form.
Okay one way to do this.
Create a List<UserControl1> private member on your form called say _myUserControls
In your Addnew Handler add it to the list.
If you have a remove button, don't forget to remove from _myUserControls as well.
Add a Reset method to your UserControl1, that does what it needs to do.
Then in your Reset all button click handler
foreach(UserControl1 ctrl in _myUserControls)
{
ctrl.Reset();
}
Jobs a good 'un
The answer I referred you to in comments, would be a way of finding all instances of your UserControl1 class, so you wouldn't need an internal list.
It seems like a straight forward thing, but I can't figure it out.
How can I check if a certain button was clicked from user control?
my user control is uc_test and button name is btnTest .
I assume its some sort of event handler added to uc_test.btnTest ?
I'm working in WinForms.
It sounds like you've created a button but want to make it do something on click. I don't often use Winforms but from memory double-clicking on the control in the form should automatically create a btnTest_Click method. If not, just go to code and put in a method like:
protected void btnTest_Click(object sender, Eventargs e)
{
//do something
}
Then set in the properties of the button the OnClick event to btnTest_Click.
I'm creating a custom dropdown box, and I want to register when the mouse is clicked outside the dropdown box, in order to hide it. Is it possible to detect a click outside a control? or should I make some mechanism on the containing form and check for mouseclick when any dropdownbox is open?
So I finally understand that you only want it to close when the user clicks outside of it. In that case, the Leave event should work just fine... For some reason, I got the impression you wanted it to close whenever they moved the mouse outside of your custom dropdown. The Leave event is raised whenever your control loses the focus, and if the user clicks on something else, it will certainly lose focus as the thing they clicked on gains the focus.
The documentation also says that this event cascades up and down the control chain as necessary:
The Enter and Leave events are hierarchical and will cascade up and down the parent chain until the appropriate control is reached. For example, assume you have a Form with two GroupBox controls, and each GroupBox control has one TextBox control. When the caret is moved from one TextBox to the other, the Leave event is raised for the TextBox and GroupBox, and the Enter event is raised for the other GroupBox and TextBox.
Overriding your UserControl's OnLeave method is the best way to handle this:
protected override void OnLeave(EventArgs e)
{
// Call the base class
base.OnLeave(e);
// When this control loses the focus, close it
this.Hide();
}
And then for testing purposes, I created a form that shows the drop-down UserControl on command:
public partial class Form1 : Form
{
private UserControl1 customDropDown;
public Form1()
{
InitializeComponent();
// Create the user control
customDropDown = new UserControl1();
// Add it to the form's Controls collection
Controls.Add(customDropDown);
customDropDown.Hide();
}
private void button1_Click(object sender, EventArgs e)
{
// Display the user control
customDropDown.Show();
customDropDown.BringToFront(); // display in front of other controls
customDropDown.Select(); // make sure it gets the focus
}
}
Everything works perfectly with the above code, except for one thing: if the user clicks on a blank area of the form, the UserControl doesn't close. Hmm, why not? Well, because the form itself doesn't want the focus. Only controls can get the focus, and we didn't click on a control. And because nothing else stole the focus, the Leave event never got raised, meaning that the UserControl didn't know it was supposed to close itself.
If you need the UserControl to close itself when the user clicks on a blank area in the form, you need some special case handling for that. Since you say that you're only concerned about clicks, you can just handle the Click event for the form, and set the focus to a different control:
protected override void OnClick(EventArgs e)
{
// Call the base class
base.OnClick(e);
// See if our custom drop-down is visible
if (customDropDown.Visible)
{
// Set the focus to a different control on the form,
// which will force the drop-down to close
this.SelectNextControl(customDropDown, true, true, true, true);
}
}
Yes, this last part feels like a hack. The better solution, as others have mentioned, is to use the SetCapture function to instruct Windows to capture the mouse over your UserControl's window. The control's Capture property provides an even simpler way to do the same thing.
Technically, you'll need to p/invoke SetCapture() in order to receive click events that happen outside of your control.
But in your case, handling the Leave event, as #Martin suggests, should be sufficient.
EDIT: While looking for an usage example for SetCapture(), I came across the Control.Capture property, of which I was not aware. Using that property means you won't have to p/invoke anything, which is always a good thing in my book.
So, you'll have to set Capture to true when showing the dropdown, then determine if the mouse pointer lies inside the control in your click event handler and, if it doesn't, set Capture to false and close the dropdown.
UPDATE:
You can also use the Control.Focused property to determine if the control has got or lost focus when using a keyboard or mouse instead of using the Capture with the same example provided in the MSDN Capture page.
Handle the Form's MouseDown event, or override the Form's OnMouseDown
method:
enter code here
And then:
protected override void OnMouseDown(MouseEventArgs e)
{
if (!theListBox.Bounds.Contains(e.Location))
{
theListBox.Visible = false;
}
}
The Contains method old System.Drawing.Rectangle can be used to indicate if
a point is contained inside a rectangle. The Bounds property of a Control is
the outer Rectangle defined by the edges of the Control. The Location
property of the MouseEventArgs is the Point relative to the Control which
received the MouseDown event. The Bounds property of a Control in a Form is
relative to the Form.
You are probably looking for the leave event:
http://msdn.microsoft.com/en-us/library/system.windows.forms.control.leave.aspx
Leave occurs when the input focus leaves the control.
I just wanted to share this. It is probably not a good way of doing it that way, but looks like it works for drop down panel that closes on fake "MouseLeave", I tried to hide it on Panel MouseLeave but it does not work because moving from panel to button leaves the panel because the button is not the panel itself. Probably there is better way of doing this but I am sharing this because I used about 7 hours figuring out how to get it to work. Thanks to #FTheGodfather
But it works only if the mouse moves on the form. If there is a panel this will not work.
private void click_to_show_Panel_button_MouseDown(object sender, MouseEventArgs e)
{
item_panel1.Visible = true; //Menu Panel
}
private void Form1_MouseMove(object sender, MouseEventArgs e)
{
if (!item_panel1.Bounds.Contains(e.Location))
{
item_panel1.Visible = false; // Menu panel
}
}
I've done this myself, and this is how I did it.
When the drop down is opened, register a click event on the control's parent form:
this.Form.Click += new EventHandler(CloseDropDown);
But this only takes you half the way. You probably want your drop down to close also when the current window gets deactivated. The most reliable way of detecting this has for me been through a timer that checks which window is currently active:
[System.Runtime.InteropServices.DllImport("user32.dll")]
static extern IntPtr GetForegroundWindow();
and
var timer = new Timer();
timer.Interval = 100;
timer.Tick += (sender, args) =>
{
IntPtr f = GetForegroundWindow();
if (this.Form == null || f != this.Form.Handle)
{
CloseDropDown();
}
};
You should of course only let the timer run when the drop down is visible. Also, there's probably a few other events on the parent form you'd want to register when the drop down is opened:
this.Form.LocationChanged += new EventHandler(CloseDropDown);
this.Form.SizeChanged += new EventHandler(CloseDropDown);
Just don't forget to unregister all these events in the CloseDropDown method :)
EDIT:
I forgot, you should also register the Leave event on you control to see if another control gets activated/clicked:
this.Leave += new EventHandler(CloseDropDown);
I think I've got it now, this should cover all bases. Let me know if I'm missing something.
If you have Form, you can simply use Deactivate event just like this :
protected override void OnDeactivate(EventArgs e)
{
this.Dispose();
}