How do I check whether a button is disabled in an if statement?

mrjj

@Dextank
Hi and welcome to the forums

Ok if the same code works in a button slot function
then it can find the gif file and the actual code works.

Then How do you call that piece of code ?

For every other button, when disabled, it/you should call that code to check
if to play the movie.

Can you show - how you disable one of the buttons and how
you call the code you shown here ?

Pl45m4

@Dextank said in How do I check whether a button is disabled in an if statement?:

I want it to work throughout my entire program

If you want to start the video as soon as (and every time) all of your buttons are disabled, you can send a custom signal to a slot, where you put your if-clause. Then emit this signal every time after you disable one of these buttons in your code. This will lead to your if-clause, check whether the if-statement is true or not and your video should start playing afterwards.

@Dextank said in How do I check whether a button is disabled in an if statement?:

It does not work even if I just do one button, the video plays and I tested that it the code.

Of course this cannot work, if you disable buttons on runtime and the program already went through your if-clause (with some of the buttons still enabled).

Dextank

@Pl45m4 Ok, so i looked at what you wrote and I managed to fix it by putting the if statement in every single function for every button that gets disabled. I'm not entirely sure if this is what you wanted me to do or if it is an ideal solution but I'll mark this topic as solved anyway. Thank you for your help.

Pl45m4

@Dextank

Not 100% :)
You have many lines of duplicate code now. Are you aware of the Signal & Slot mechanism in Qt?
You can keep your if-statement in one function (slot) and call it (by emiting a signal) whenever one of your buttons gets disabled.

Dextank

@Pl45m4 So basically you want me to make another function with the if statement in it and then connect all my buttons to that function? This would mean that all my buttons now have two functions connected to them, is this alright?

Pl45m4

@Dextank said in How do I check whether a button is disabled in an if statement?:

So basically you want me to make another function with the if statement in it and then connect all my buttons to that function?

I want nothing :-) Do what you want :-) But you asked for help. You can keep your solution if you want to, but, as I said, it's not the cleanest one.

@Dextank said in How do I check whether a button is disabled in an if statement?:

This would mean that all my buttons now have two functions connected to them, is this alright?

Why two?

This is how *I* would do it:

// Your class header (eg. MainWindow)

signals:
       void btnDisabled();

public slots:
       void playVideo();

// Constructor
{

    ui->setupUi(this);
    connect(this, &MainWindow::btnDisabled, this, &MainWindow::playVideo);
}


void MainWindow::randomFnct()
{
   // Some code
   
   // eg. one of your buttons gets disabled here
   ui->randomButton->setDisabled(true);
   // emit signal afterwards
   emit btnDisabled();
}

void MainWindow::playVideo()
{
   // your If-clause here
}

Dextank

@Pl45m4 I used your code as a basis for what I wanted to do and it seems to work exactly the way I wanted it to, my program also looks a lot cleaner now. Thanks for all your help.

Kent-Dorfman

One final thought that I didn't see mentioned above.
In C++ booleans don't need to (and shouldn't) be directly compared to true/false. It is adequate to say

if (something()) { // true
    do_this(); 
} else if (!something_else()) { // false
    do_that(); 
}

Pl45m4

@Kent-Dorfman said in How do I check whether a button is disabled in an if statement?:

if (something())

something() only if it's a bool function ;-)

Kent-Dorfman

@Pl45m4 said in How do I check whether a button is disabled in an if statement?:

something() only if it's a bool function ;-)

Well, sort of...An integer function that returns zero is said to be "false", and (!0 == true). Of course that kind of logic in C++ is highly discouraged, even though it is technically supported.

Pl45m4

@Kent-Dorfman

I meant, when something is a bool something, then it would be if(something){} not if(something( ) ) .