I have a user control(VCtrlDetails in the code below) that hosts a data grid(detailsGrid) which is private.
Now, i have this control loaded in another user control(UcResult_Details) and i want to handle grid selection changed event in this another user control.
public partial class VCtrlDetails : UserControl
{
public event EventHandler<bool> EnableEditTemplateButton;
private void InitializeComponent()
{
private System.Windows.Forms.DataGrid detailsGrid;
this.detailsGrid.SelectionChanged += new
System.EventHandler(this.detailsGrid_SelectionChanged);
}
private void detailsGrid_SelectionChanged(object sender, EventArgs e)
{
EnableEditButton?.Invoke(this, IsApproved());
}
public bool IsApproved()
{ }
}
public partial class UcResult_Details : UserControl
{
private readonly VCtrlDetails vCtrlDetails;
UcResult_Details()
{
//Need to subscribe to vCtrlDetails' grid selection changed event here in this ctor
}
}
I'm not that well versed with event handlers, so stuck with the solution as the grid object is private in the user control 'VCtrlDetails', so cannot directly do something like:
vCtrlDetails.detailsGrid.SelectionChanged += DetailsGrid_SelectionChanged
You need to bubble the event up and out of the VCtrlDetails class. You could do so by creating an event within the VCtrlDetails class and allowing your UcResult_Details class to subscribe to it.
public partial class VCtrlDetails : UserControl
{
public event EventHandler<bool> EnableEditTemplateButton;
public event EventHandler<EventArgs> DetailsGridSelectionChanged;
private void InitializeComponent()
{
private System.Windows.Forms.DataGrid detailsGrid;
this.detailsGrid.SelectionChanged += new
System.EventHandler(this.detailsGrid_SelectionChanged);
}
private void detailsGrid_SelectionChanged(object sender, EventArgs e)
{
EnableEditButton?.Invoke(this, IsApproved());
//Raise your custom event
DetailsGridSelectionChanged?.Invoke(this, e);
}
public bool IsApproved()
{
}
}
public partial class UcResult_Details : UserControl
{
private readonly VCtrlDetails vCtrlDetails;
UcResult_Details()
{
//Need to subscribe to vCtrlDetails' grid selection changed event here in this ctor
this.vCtrlDetails.DetailsGridSelectionChanged += new
EventHandler(this.vCtrlDetailsSelectionChanged);
}
private void vCtrlDetailsSelectionChanged(object sender, EventArgs e)
{
//Do whatever
}
}
Related
I have 2 controls that inherit UserControl
one is a container and the other is a collection of basic text boxes lables etc. hereby labeled as ContainerControl and ComboControl.
ContainerControl contains a List<ComboControl> and a foreach loop that adds them to a FlowLayoutPanel. ComboControl has a button that I would like to be used to clear itself from its parent's List.
I am not sure what the best way of doing this would be. this.parent and cast to ContainerControl or would Dispose() work? I'm fairly sure I could pass a ref to the List, but that sounds needlessly messy...
public partial class ContainerControl : UserControl
{
List<ComboControl> ComboControls = new List<ComboControl>();
...
//procederaly generate and fill ComboControls here
...
foreach (ComboControl value in ComboControls)
{
this.flowLayoutTable.Controls.Add(value);
}
...
}
public partial class ComboControl : UserControl
{
private void BtnDel_Click(object sender, EventArgs e)
{
//what goes here
}
...
}
Along the lines of what Zohar Peled said, something like this to remove a control to avoid leaking resources.
private void cleanup(Control c)
{
foreach(Control child in c.Controls)
cleanup(child);
if (c.Parent != null)
{
c.Parent.Controls.Remove(c);
c.Dispose();
}
}
For scenario like this i would use a custom event to send a delete request to parent control :
your ComboControl with Custom Event :
//Create Custom Event
public delegate void DeleteControlDelegate(object sender);
public partial class ComboControl : UserControl
{
//Custom Event to send Delete request
public event DeleteControlDelegate DeleteControlDelegate;
public ComboControl()
{
InitializeComponent();
}
//Invoke Custom Event
private void OnDeleteControl(object sender)
{
DeleteControlDelegate?.Invoke(sender);
}
private void BtnDel_Click(object sender, EventArgs e)
{
//On ButtonClick send Delete request
OnDeleteControl(this);
}
}
and in your ContainerControl subscribe to event of each ComboControl :
List<ComboControl> _comboControls = new List<ComboControl>();
public ContainerControl()
{
InitializeComponent();
}
private void ContainerControl_Load(object sender, EventArgs e)
{
_comboControls.Add(new ComboControl());
_comboControls.Add(new ComboControl());
_comboControls.Add(new ComboControl());
foreach (ComboControl value in _comboControls)
{
flowLayoutPanel.Controls.Add(value);
//Subscribe to Custom Event here
value.DeleteControlDelegate += Value_DeleteControlDelegate;
}
}
private void Value_DeleteControlDelegate(object sender)
{
//When Raised Delete ComboControl
flowLayoutPanel.Controls.Remove((Control) sender);
}
}
In the MainWindow constructor, I am registering an event handler:
public partial class MainWindow : Window, INotifyPropertyChanged
{
public MainWindow()
{
InitializeComponent();
pageViewDocText = new PageViewDocText();
framePageDocFieldDetail.Content = pageViewDocText;
pageViewDocText.NewPageIRPRO += new GabeLib.SearchCls.DocEventHandler(ViewIPRO);
}
protected void ViewIPRO(string IRPOlink) // ...
}
public partial class PageViewDocText : Page, INotifyPropertyChanged
{
public event GabeLib.SearchCls.DocEventHandler NewPageIRPRO;
private void btn_PageBreakNext(object sender, RoutedEventArgs e)
{
// this fires but NewPageIRPRO is null
if (NewPageIRPRO != null)
{
NewPageIRPRO("dummylink");
}
}
}
But in PageViewDocText, NewPageIRPRO is null
What am I doing wrong?
From PageViewDocText, I want to call MainWindow.ViewIPRO.
This event handler fires and is registered the line below pageViewDocText.NewPageIRPRO +=
App.StaticGabeLib.Search.NewDocIRPRO += new GabeLib.SearchCls.DocEventHandler(ViewIPRO);
Looks like you are calling an event from another class (not listed) and there is a missing delegate.
Try this code:
public partial class MainWindow : Window, INotifyPropertyChanged
{
public MainWindow()
{
InitializeComponent();
pageViewDocText = new PageViewDocText();
framePageDocFieldDetail.Content = pageViewDocText;
pageViewDocText.PageBreakNext += new PageBreakNext(ViewIPRO);
}
protected void ViewIPRO(string IRPOlink) // ...
}
public partial class PageViewDocText : Page, INotifyPropertyChanged
{
public delegate void PageBreakNext(string IRPOlink);
public event PageBreakNext PageBreak;
private void btn_PageBreakNext(object sender, RoutedEventArgs e)
{
// this fires but NewPageIRPRO is null
if (PageBreak != null)
{
PageBreak("dummylink");
}
}
}
I've followed this question and tried to build my solution. The problem is that 'UserControlButtonClicked' appears to be null! So 'UserControlButtonClicked(this, EventArgs.Empty)' inside the if, doesn't run, and the method 'addStepContent' in the parent page is never called.
UserControl 'StepsBar'
public sealed partial class StepsBar : UserControl
{
public event EventHandler UserControlAddStepContent;
[...]
public StepsBar()
{
this.InitializeComponent();
Image step_1 = new Image();
ButtonInfo step_1Info = new ButtonInfo();
step_1Info.Add((int)stepNumber.one, (int)stepStatus.normal);
step_1.Tag = step_1Info;
step_1.Source = setBackground((int)stepStatus.normal);
step_1.Tapped += stepTapped;
[...]
}
public void stepTapped(Object sender, RoutedEventArgs e)
{
[...]
if (step != null)
{
[...]
firePageEvent();
}
}
public void firePageEvent()
{
if (UserControlAddStepContent != null)
{
UserControlAddStepContent(this, EventArgs.Empty);
}
}
Parent Page
public Violation()
{
this.InitializeComponent();
StepsBar stepsBar = new StepsBar();
stepsBar.UserControlAddStepContent += new EventHandler(addStepContent);
}
private void addStepContent(object sender, EventArgs e)
{
CheckBox check_1 = new CheckBox();
check_1.Content = "Check me!";
bodyStackPanel.Children.Add(check_1);
}
This assumes that you want to use an existing delegate rather than make your own and you aren't passing anything specific to the parent page by event args.
In the user control's code-behind (adapt as necessary if not using code-behind or C#):
public partial class MyUserControl : System.Web.UI.UserControl
{
public event EventHandler UserControlButtonClicked;
private void OnUserControlButtonClick()
{
if (UserControlButtonClicked != null)
{
UserControlButtonClicked(this, EventArgs.Empty);
}
}
protected void TheButton_Click(object sender, EventArgs e)
{
// .... do stuff then fire off the event
OnUserControlButtonClick();
}
// .... other code for the user control beyond this point
}
In the page itself you subscribe to the event with something like this:
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
// hook up event handler for exposed user control event
MyUserControl.UserControlButtonClicked += new
EventHandler(MyUserControl_UserControlButtonClicked);
}
private void MyUserControl_UserControlButtonClicked(object sender, EventArgs e)
{
// ... do something when event is fired
}
}
Solved. The problem was this, on the parent page.
StepsBar stepsBar = new StepsBar();
stepsBar.UserControlAddStepContent += new EventHandler(addStepContent);
The istance of StepsBar was not added to the page. D'OH!
So here's what I've done:
stepsBar.UserControlAddStepContent += new EventHandler(addStepContent);
and on the xaml of the parent page:
<local:StepsBar x:Name="stepsBar"/>
I have a UserControl, that contains a panel, the panel contains a picture box.
When I MouseMove over the Picture Box, I want to update a label on the MainForm.
I have a get/set method on the main form, but how do I use it?? thanks
public partial class MainForm : Form
{
public MainForm()
{
InitializeComponent();
}
public String MouseCords
{
get { return this.MouseCordsDisplayLabel.Text; }
set { this.MouseCordsDisplayLabel.Text = value; }
}
}
public partial class ScoreUserControl : UserControl
{
public ScoreUserControl()
{
InitializeComponent();
}
private void ScorePictureBox_MouseMove(object sender, MouseEventArgs e)
{
// MainForm.MouseCords("Hello"); //What goes here?
}
}
Actually it's possible to do in your case like:
((MainForm)this.ParentForm).MouseCords = "Some Value Here";
But the right way is with events like Felice Pollano mentinoed:
public partial class MainForm : Form
{
public MainForm()
{
InitializeComponent();
this.myCustomControlInstanse.PicureBoxMouseMove += new EventHandler<StringEventArgs>(myCustomControlInstanse_PicureBoxMouseMove);
}
private void myCustomControlInstanse_PicureBoxMouseMove(object sender, StringEventArgs e)
{
this.MouseCordsDisplayLabel = e.Value // here is your value
}
}
public class StringEventArgs : EventArgs
{
public string Value { get; set; }
}
public partial class ScoreUserControl : UserControl
{
public event EventHandler<StringEventArgs> PicureBoxMouseMove;
public void OnPicureBoxMouseMove(String value)
{
if (this.PicureBoxMouseMove != null)
this.PicureBoxMouseMove(this, new StringEventArgs { Value = value });
}
public ScoreUserControl()
{
InitializeComponent();
}
private void ScorePictureBox_MouseMove(object sender, MouseEventArgs e)
{
this.OnPicureBoxMouseMove("Some Text Here");
}
}
Ideally, you should raise an event for the same.
Create a delegate
public delegate void Update();
in the user control
public class MyUserControl : UserControl
{
public event Update OnUpdate;
}
On the main form register a handler for the user controls event.
public class Main
{
public Main()
{
myUserControl.OnUpdate += new Update(this.UpdateHandler);
}
void UpdateHandler()
{
//you can set the delegate with sm arguments
//set a property here
}
}
On user control,
To raise an event on button click
do this
OnUpdate();
This might give you an idea...
public partial class ScoreUserControl : UserControl
{
public ScoreUserControl()
{
InitializeComponent();
}
private void ScorePictureBox_MouseMove(object sender, MouseEventArgs e)
{
// MainForm.MouseCords("Hello"); //What goes here?
MainForm parent = this.ParentForm as MainForm;
if (parent != null) parent.MouseCordsDisplayLabel.Text = "Hello";
}
}
You have several options:
Create an event on the user control and have to form listen to it (I think this is the recommended way by most C# programmers).
Pass a reference to the main form to the User Control (in the constructor). This way, the user control knows about its MainForm.
Cast this.ParentForm to the MainForm class, then you have the reference.
Options 2 and 3 are somewhat more comfortable and lazy, but the cost is that the user control has to know about the specific class MainForm. The first option has the advantage that you could reuse the user control in another project, because it does not know about the MainForm class.
You should publish an event from the user control and subscribe to it from the main form.
At least this is the pattern suggested for winform. In any case the idea is to make the control "observable" from the agents who need to see the coords, instead of using it as a driver to update the interested agents.
I'm trying to subscribe to the the save button event of a user control that is launched in a separate radwindow from the calling parent. but I am getting object not initialized error, I know why but what am I missing?
Update: I found my error but it appears that if (this.SaveEvent!= null) in the ControlBase is always null
Parent Control Code:
public partial class myControl : ControlBase
{
private myChildControl __myChildControl;
private void myControl_PreRender(object sender, EventArgs e)
{
// error occurs here
//this.__myChildControl.SaveEvent += new myChildControl.SaveEventHandler(__myChildControl_SaveEvent);
// found my error
this.SaveEvent += new myChildControl.SaveEventHandler(__myChildControl_SaveEvent);
}
private void __myChildControl _SaveEvent(object sender, CustomEventArgs e)
{
this.Label1.Text = e.CustomEventArg1.ToString();
this.Label2.Text = e.CustomEventArg2.ToString();
}
}
Child Control Launched in RadWindow:
public partial class myChildControl : ControlBase
{
protected void btnSave_OnClick(object sender, EventArgs e)
{
CustomEventArgs _cea = new CustomEventArgs {CustomEventArg1 = 123, CustomEventArg2 = 12};
callBaseMethod(_cea);
}
}
ControlBase Code:
public class ControlBase : UserControl
{
public event CustomEventHandler SaveEvent;
public delegate void CustomEventHandler(object sender, CustomEventArgs e);
internal void callBaseMethod(CustomEventArgs cea)
{
if (this.SaveEvent!= null)
{
this.SaveEvent(this, cea);
}
}
}
CustomEventArgs class:
public class CustomEventArgs : EventArgs
{
public int CustomEventArgs1 { get; set; }
public int CustomEventArgs2 { get; set; }
}
This isn't possible in codebehind: the RadWindow presents a separate aspx/ascx page altogether that is linked to the main page through javascript alone.
What you need to do is handle the RadWindow OnClientClose event in javascript, then fire something in the parent page that performs the appropriate tasks.