Re: Can't change a button't text at runtime anymore?????? - C# Discussion Boards

Re: Can't change a button't text at runtime anymore??????

24-Jan-12 20:29

Hi again

What I mean with "nothing happens" is that the button btn's text is still By.Even if the bool folder's property Visible is changed to true. I have tried

I have the code in the buttons click event.

private void btn_Click(object sender, EventArgs e)
{
        if (folder.Visible==true )
        {
           btn.Text = "Hi"; 
         }         
         else
         {
            btn.Text = "By";
         }
               
}

I have tried btn.Invalidate(); and Form1.Invalidate(); it didn't help. And I also tried with Refresh() and Update() on both btn and Form1.

Dear KP Lee

I don't understand how to or what you mean I should do
"I fixed that by assigning a delegate in the winapp, running the calculations on another thread and calling the delegate."

Many Thanks
Fia

lukeer24-Jan-12 21:15

lukeer

24-Jan-12 21:15

I'd try to change the condition to

if (btn.Text == "By")

just to try if the Text change works.

If it does, you should investigate how folder.Visible is connected to your button text.

Ciao,

luker

Re: Can't change a button't text at runtime anymore??????

OriginalGriff24-Jan-12 22:21

Re: Can't change a button't text at runtime anymore??????

24-Jan-12 22:21

The other thing to check is that the click event is hooked to the event handler: put a breakpoint on the first line to make sure it is being executed, and then single step through.

Ideological Purity is no substitute for being able to stick your thumb down a pipe to stop the water

fiaolle24-Jan-12 22:42

Re: Can't change a button't text at runtime anymore??????

24-Jan-12 22:42

Hi Thanks for your answers.

I have already stepped through the code and it's running as it should, but the button's Text still doesn't change.

I don't understand what to do????.

Many Thanks
Fia

OriginalGriff24-Jan-12 22:55

Re: Can't change a button't text at runtime anymore??????

24-Jan-12 22:55

OK: I took an existing form, and dropped a button on it.
I double clicked the button and in the handler method that came up:

private void button1_Click(object sender, EventArgs e)
    {
    button1.Text = button1.Text == "Hello" ? "Goodbye" : "Hello";
    }

When I ran the app, the button caption was "button1".
When I pressed it the first time, it changed to "Goodbye"
A second click, it became "Hello".
Third click, back to "Goodbye", and round and round.

What am I doing that is different to you, or you doing that is different to me?

Ideological Purity is no substitute for being able to stick your thumb down a pipe to stop the water

fiaolle24-Jan-12 23:35

Re: Can't change a button't text at runtime anymore??????

24-Jan-12 23:35

Hi I can't see any difference.

Here is my code.

private void btn_Click(object sender, EventArgs e)
{
        if (folder.Visible==true )
        {
           btn.Text = "Hi"; 
         }         
         else
         {
            btn.Text = "By";
         }
}

The variable folder is just a bool variable. When I debug my code I can see that it runs as it should, but still the button's Text doesn't change.
I don't know if it has anything to do with the problem, but I have a FileLListbox and a FolderListBox from Alva on the form. Should that be the problem.

Many Thanks
Fia

OriginalGriff24-Jan-12 23:37

Re: Can't change a button't text at runtime anymore??????

24-Jan-12 23:37

Try something quick: Put a breakpoint on the if line of the handler, and change teh button text in the designer to "TEST".
Run your app, and press the button. Look at btn.Text in the debugger - is it "TEST"?

Ideological Purity is no substitute for being able to stick your thumb down a pipe to stop the water

fiaolle25-Jan-12 0:05

Re: Can't change a button't text at runtime anymore??????

25-Jan-12 0:05

Hi
I tried that and the text is "Test". I tried also to remove all Alva controls, but I still can't change the text on the button. Frown | :(

Thanks
Fia

OriginalGriff25-Jan-12 0:19

Re: Can't change a button't text at runtime anymore??????

25-Jan-12 0:19

So at least we can be absolutely sure that the right button is hooked up - if you replace the handler content with

btn.Text = "WTF!";

and single step over that one instruction, is the text still "Test" or "WTF!" - I'm just wondering if the text is being changed back somewhere else (which would be a weird thing to do automatically)

Ideological Purity is no substitute for being able to stick your thumb down a pipe to stop the water

fiaolle25-Jan-12 0:28

Re: Can't change a button't text at runtime anymore??????

25-Jan-12 0:28

Hi
It changes to "WTF" in the code, but after the event. The buttons text is "Test"?????

Thanks
Fia

OriginalGriff25-Jan-12 0:32

Re: Can't change a button't text at runtime anymore??????

25-Jan-12 0:32

Something has got to be changing it back!

Delete it.
Rebuild.
That should give you any errors that refer to it.
If there aren't any, put it back and repeat the above, see if it works.

Either that or you have a PC full of malevolent pixies... Laugh | :laugh:

Ideological Purity is no substitute for being able to stick your thumb down a pipe to stop the water

Pete O'Hanlon25-Jan-12 3:41

Pete O'Hanlon

25-Jan-12 3:41

Put a breakpoint in your code in this routine. Search through your code for all instances of the word Test and put breakpoints on them all - each and everyone. Run the program again and note each breakpoint you hit - you must be resetting the text back to Test after you have left this routine.

Forgive your enemies - it messes with their heads

"Mind bleach! Send me mind bleach!" - Nagy Vilmos

My blog | My articles | MoXAML PowerToys | Mole 2010 - debugging made easier - my favourite utility

Re: Can't change a button't text at runtime anymore??????

KP Lee24-Jan-12 12:02

KP Lee

24-Jan-12 12:02

Trying that statement shouldn't even compile. Assuming you didn't complete the statement you really used (with a semi-colon,) this will normally cause the button to refresh and show "Hi" (Without quotes) like your other responder said.

You can try to force a refresh with an .Invalidate

Once, I tried to execute complex logic and print intermediate results by modifying text boxes' .Text property. Wanted to know why that wasn't working. Your winapp has to be idle and waiting for a response before it will render the changes.

I fixed that by assigning a delegate in the winapp, running the calculations on another thread and calling the delegate.

Re: Can't change a button't text at runtime anymore??????

OOPSEP25-Jan-12 1:15

OOPSEP

25-Jan-12 1:15

private void btn_Click(object sender, EventArgs e)
{
        if (folder.Visible==true )
        {
           btn.Text = "Hi";
         }
         else
         {
            btn.Text = "By";
         }

}

Make sure your property folder.Visible is change when click state
btn.Text = folder.Visible?"Hi":By;
folder.Visible=!folder.Visible; // reset state here

Re: Can't change a button't text at runtime anymore??????

fiaolle25-Jan-12 2:30

Re: Can't change a button't text at runtime anymore??????

25-Jan-12 2:30

Hi I am changing the folder to visible or not visible. But nothing is helping me.

Thanks
Fia

BillWoodruff25-Jan-12 3:41

BillWoodruff

25-Jan-12 3:41

Given all the responses above, clearly something very weird is happening here.

Are you talking about a standard WinForms Button object here ?

Also: what is "folder," exactly: that's an odd name for a Control. And, if "folder" has a boolean "visible" property, you can use it directly : if (folder.Visible) ...

You mention: "I don't know if it has anything to do with the problem, but I have a FileLListbox and a FolderListBox from Alva on the form. Should that be the problem."

Is "folder" by chance an "Alva" control ?

What are the "Alva" controls, and, is it possible your use of them has introduced some kind of modification that is indirectly changing the way other controls behave ?

good luck, Bill

"Science is facts; just as houses are made of stones: so, is science made of facts. But, a pile of stones is not a house, and a collection of facts is not, necessarily, science." Henri Poincare

Re: Can't change a button't text at runtime anymore??????

fiaolle25-Jan-12 4:17

Learning C# custom controls

25-Jan-12 4:17

Hi Thanks for all your replies. I have found my error.
I used InitializeComponent(); both in the constructor Form1() and in
Form1_Load(object sender, EventArgs e)

I am so sorry for my misstake, but know it's working as it should Big Grin | :-D

Many thanks
Fia

thechazm24-Jan-12 5:53

thechazm

24-Jan-12 5:53

Does anyone have a good reference to a site or a book that focus's on custom controls? I have watched all the youtube videos. Also I completed the training at learnvisualstudio's website.

Thanks,
TheChazm

modified 24-Jan-12 15:11pm.

fjdiewornncalwe24-Jan-12 9:11

fjdiewornncalwe

24-Jan-12 9:11

C# Custom Control Featuring a Collapsible Panel[^]. A good example.
User Control articles on CP[^]
Custom Control articles on CP[^]
Walkthrough: Authoring a Composite Control with Visual C#[^]. If you want a different dotNet version, just pick it from the "Other Versions" link just under the title in the article.
C# Tutorial: A gauge control with all source code, .net 2.0[^] This is a good tutorial, but is only for dotNet 2.0.

I wasn't, now I am, then I won't be anymore.

Dean Oliver24-Jan-12 19:00

Dean Oliver

24-Jan-12 19:00

http://msdn.microsoft.com/en-us/library/6hws6h2t.aspx[^]

hope you find this link useful.

BillWoodruff25-Jan-12 3:49

BillWoodruff

25-Jan-12 3:49

If by "custom controls" you mean UserControls in WinForms, I have benefited greatly from Matthew MacDonald's excellent book "Pro .NET 2.0 Windows Forms and Custom Controls in C#"[^].

Yes, that's quite an old book now (2004), but the author goes into many details, such as defining custom design-time adornments, and complex Property Browser selection mechanisms for custom controls, in a way that I have found clearer than any material I have read since.

"Science is facts; just as houses are made of stones: so, is science made of facts. But, a pile of stones is not a house, and a collection of facts is not, necessarily, science." Henri Poincare