User control events on windows form

Question

I have a user control that contains a tab control on it. The control is used on a form. When I debug/test the control events (by running the app and loading the form), they don't seem to be firing on the form. I want to take action when the user changes tabs.

Thanks in advance.

Daniel

Mike Gold · Answer

Here is a full sample: User Control: namespace TestPropogateTabEvent { public partial class UserControlWithTab : UserControl { public UserControlWithTab() { InitializeComponent(); } public delegate void TabSelectionEventHandler ( object sender EventArgs e); public event TabSelectionEventHandler PropogateSelectionChange; private void tabControl1_SelectedIndexChanged( object sender EventArgs e) { if (PropogateSelectionChange != null ) { PropogateSelectionChange(sender e); } } } } Form Class: namespace TestPropogateTabEvent { public partial class Form1 : Form { public Form1() { InitializeComponent(); userControlWithTab1.PropogateSelectionChange += new UserControlWithTab . TabSelectionEventHandler (userControlWithTab1_PropogateSelectionChange); } void userControlWithTab1_PropogateSelectionChange( object sender EventArgs e) { MessageBox .Show( Tab In User Control Pressed ); } } }

Mike Gold · Answer

Hi Daniel I've constructed a sample in the reply below. basically you are bubbling up the event from the tab in the user control into the form.

Daniel · Answer

Here is my code. I can't seemed to get it working UserControl.cs (declared outside of class) public delegate void TabPageClickHandler(object sender TabPageClickEventArgs e); (declared inside of class) public event TabPageClickHandler TabPageClick; protected void OnTabPageClick(string tabName) { //if anyone listening for event data //if an object is registered to be notifed of the event if (TabPageClick != null) { TabPageClickEventArgs args = new TabPageClickEventArgs(); args.TabName = tabName; TabPageClick(this args); MessageBox.Show(OnTabPageClick fired); } } //To run my test private void tabClassProdEng_Selected(object sender TabControlEventArgs e) { OnTabPageClick(e.TabPageIndex.ToString()); } Form.cs (within initializecomponent() section) ucProdEngineering.TabPageClick +=new TabPageClickHandler(ucProdEngineering_TabPageClick); // I get an error above: The name 'ucProdEngineering_TabPageClick' does not exist in the current context Thanks. Daniel

Daniel · Answer

Thanks Jan. Can you recommend the proper event to put the user control side code into? tabPage_Click tabControl_TabIndexChanged ??? Is there a benefit to one over the other....? Thanks Daniel

Daniel · Answer

Thanks a million for posted an example of this. I will try it tomorrow and let you know how it works out. I really appreciate the help. Daniel

Jan Montano · Answer

UserControl1.cs: public event TabControlEventHandler TabSelectedEvent; tabControl1.Selected += new TabControlEventHandler(tabControl1_Selected); void tabControl1_Selected(object sender TabControlEventArgs e) { TabSelectedEvent(sender e); } Form1.cs userControl11.TabSelectedEvent+= new TabControlEventHandler(userControl11_TabSelectedEvent); void userControl11_TabSelectedEvent(object sender TabControlEventArgs e) { MessageBox.Show(e.TabPageIndex.ToString()); } *If you want to handle tabpage_click event just call the tabselectedevent from the tabpage_click event instead.

Daniel · Answer

Hi Richard I have read some initial info on custom events but may need some additional help on the concept. I want to handle the TabPage_click event (on my user control) on the form that that the control resides on. I am not quite sure how to pull that off. Thanks in advance for any help you or ANYONE can provide. Thanks Daniel

Daniel · Answer

Thanks for the post Richard. I will google customer events first and then contain post back if I am still having problems. Daniel

Richard Blythe · Answer

The event is fired but it is only visible inside the confines of you usercontrol class. If you want to trap the event inside the form you will need to write a custom event. Aw it ain't that hard! Do a google search on custom events and if you are still confused let me know and I'll help you. Cheers! Richard