Detect if any of controls inside a TableLayoutPanel is clicked
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Hello ! Is there any way to detect if any of the controls inside a TableLaoutPanel is clicked ? ( I mean without using Click event for each control ). I try using MouseClick's event of TableLayoutPanel , but this doesn't fire when a control is clicked. Thank you !
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Ok , but what is going to handle this event ? Because if he's going to handle the click action , this is the same as using all control's click event.
Yes. You have to wire up the ``Click`` event of each control to a central Click handler to do what you want. It seems like your concern is based on the assumption that only one handler can be assigned to the ``Click`` event. That is NOT the case. Multiple handlers can be assigned to the same event and they will all get executed. So, you CAN have your general ``Click`` event handler for every control that you want to be notified for and you can have individual ``Click`` handlers for each control for specific functionality for whatever a certain button, or whatever controls, is going to do when clicked.
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Dave Kreskowiak -
Ok , but what is going to handle this event ? Because if he's going to handle the click action , this is the same as using all control's click event.
What's the trouble with using all control's click event?
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Yes. You have to wire up the ``Click`` event of each control to a central Click handler to do what you want. It seems like your concern is based on the assumption that only one handler can be assigned to the ``Click`` event. That is NOT the case. Multiple handlers can be assigned to the same event and they will all get executed. So, you CAN have your general ``Click`` event handler for every control that you want to be notified for and you can have individual ``Click`` handlers for each control for specific functionality for whatever a certain button, or whatever controls, is going to do when clicked.
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Dave Kreskowiaksorry , but I have a central Click event. The problem is that the code inside the click event is depending from the case where the click event is fired from user action ( so a user has clicked ) , or is fired from code. I can't distinguish these 2 cases , then I ask if is possible to detect a click fro the TableLayoutPanel in general.
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What's the trouble with using all control's click event?
The problem is that the code inside the click event is depending from the case where the click event is fired from user action ( so a user has clicked ) , or is fired from code. I can't distinguish these 2 cases , then I ask if is possible to detect a click fro the TableLayoutPanel in general.
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The problem is that the code inside the click event is depending from the case where the click event is fired from user action ( so a user has clicked ) , or is fired from code. I can't distinguish these 2 cases , then I ask if is possible to detect a click fro the TableLayoutPanel in general.
I would say this is the point where you should ask yourself "why is this getting weird?" - and my answer would be "because a previous design decision was wrong/not optimal". I wouldn't trigger the Click-event programmatically. Instead I would move the code from the Click-Eventhandler into a separate method with a parameter that indicates whether it's being called from the Click-Eventhandler (= by a user-click) or from code:
SomeButton.Click += SomeButtonClicked;
void SomeButtonClicked(object sender, EventArgs e)
{
DoStuff(userClicked: true);
}void SimulateButtonClick()
{
DoStuff(userClicked: false);
}void DoStuff(bool userClicked)
{
if (userClicked)
// ...
else
// ...
} -
I would say this is the point where you should ask yourself "why is this getting weird?" - and my answer would be "because a previous design decision was wrong/not optimal". I wouldn't trigger the Click-event programmatically. Instead I would move the code from the Click-Eventhandler into a separate method with a parameter that indicates whether it's being called from the Click-Eventhandler (= by a user-click) or from code:
SomeButton.Click += SomeButtonClicked;
void SomeButtonClicked(object sender, EventArgs e)
{
DoStuff(userClicked: true);
}void SimulateButtonClick()
{
DoStuff(userClicked: false);
}void DoStuff(bool userClicked)
{
if (userClicked)
// ...
else
// ...
}Thank you , but the situation it's a little complicated and I can't use your solution. I have another Event let's say Event2 that is fired when the button's click event is executed. But this event2 can be fired even without button's click event but from another action. And if this case is true , inside the event2 button's click event is called from code. So the events are depending to each other , and I can't find other way but only to distinguish that the click's event is fired by user click or by code.
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I would say this is the point where you should ask yourself "why is this getting weird?" - and my answer would be "because a previous design decision was wrong/not optimal". I wouldn't trigger the Click-event programmatically. Instead I would move the code from the Click-Eventhandler into a separate method with a parameter that indicates whether it's being called from the Click-Eventhandler (= by a user-click) or from code:
SomeButton.Click += SomeButtonClicked;
void SomeButtonClicked(object sender, EventArgs e)
{
DoStuff(userClicked: true);
}void SimulateButtonClick()
{
DoStuff(userClicked: false);
}void DoStuff(bool userClicked)
{
if (userClicked)
// ...
else
// ...
} -
I'm thinking , is possible that when I call the click event from code , to insert an special argment on its Args , and inside the click event to check this arg ? Can this be done ?
Sure, either object sender or EventArgs e or both. I try to avoid doing that because I find it a bit messy but it'll work.
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Sure, either object sender or EventArgs e or both. I try to avoid doing that because I find it a bit messy but it'll work.
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I don't want to change the sender because I need this. Can you explain to me , how can pass a special argument and to check on the code inside ?
Just derive your custom class from EventArgs that carries your custom arguments. Then check in the called eventhandler for the type of
eand cast it to your custom class if it is the same. -
Just derive your custom class from EventArgs that carries your custom arguments. Then check in the called eventhandler for the type of
eand cast it to your custom class if it is the same. -
sorry , but I have a central Click event. The problem is that the code inside the click event is depending from the case where the click event is fired from user action ( so a user has clicked ) , or is fired from code. I can't distinguish these 2 cases , then I ask if is possible to detect a click fro the TableLayoutPanel in general.
Again, the TableLayoutPanel is NOT a control you can click on. It is an extension to other controls where it adds properties to them to change the way they layout in their parent container, such as a Form or Panel. There is no way to differentiate where a ``Click`` event came from. It's always going to be from the button itself. If you're kicking off a ``Click`` event from code, you're doing it wrong. Move the code from inside the event handler into it's own method and call it from both your code and from the ``Click`` event handler.
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Dave Kreskowiak -
Ehm. Yes. Just realized we're in the VB-Forum. Can you read C# ? Because I'm not good at writing VB ;)
class MyEventArgs : EventArgs
{
public string Foo { get; private set; }public MyEventArgs(string foo) { Foo = foo; }}
class MyButton : Button
{
public void SimulateClick(string foo)
{
base.OnClick(new MyEventArgs(foo));
}
}void SomeEventhandler(object sender, EventArgs e)
{
if(e is MyEventArgs)
{
string foo = ((MyEventArgs)e).Foo;
}
else
{
// ...
}
} -
Ehm. Yes. Just realized we're in the VB-Forum. Can you read C# ? Because I'm not good at writing VB ;)
class MyEventArgs : EventArgs
{
public string Foo { get; private set; }public MyEventArgs(string foo) { Foo = foo; }}
class MyButton : Button
{
public void SimulateClick(string foo)
{
base.OnClick(new MyEventArgs(foo));
}
}void SomeEventhandler(object sender, EventArgs e)
{
if(e is MyEventArgs)
{
string foo = ((MyEventArgs)e).Foo;
}
else
{
// ...
}
}Thank you , I understand your code. But I have a last question : Is it possible not to use your class , but this idea : When I call the Button's click event from code , I use this instruction : myButton_Click(myButton, EventArgs.Empty) Now when this event is fired from a real user click , the EventsArg is empty or not ? Because if is not empty , I can just test inside the click event , if eventArgs is empty or not ? Can this idea work ? Thank you !
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Thank you , I understand your code. But I have a last question : Is it possible not to use your class , but this idea : When I call the Button's click event from code , I use this instruction : myButton_Click(myButton, EventArgs.Empty) Now when this event is fired from a real user click , the EventsArg is empty or not ? Because if is not empty , I can just test inside the click event , if eventArgs is empty or not ? Can this idea work ? Thank you !
You could do that. If the Click-Event comes from a real click, then
eis of type MouseEventArgs. I would recommend using a custom class for two reasons: You can give it a name that explains its purpose so that your code will speak for itself. And if the need would arise to have a third cause for the event you would be out of options when testing ifeequals EventArgs.Empty or not.