Qt simple count down

Ruben12313

Good evening

Im developing a project for my Senior class and in my GUI at the moment im trying to create a simple countdown but I cant quite get it right. When I press start it increments the number by 1 value and stop does 1 decrement. I tried a simple for loop in the function but I get errors in my connect area.

Here I have it in the mainwindow.cpp above my other codes for different functions

    this->connect(this->ui->pushButton_2, SIGNAL(released()), this,SLOT(button_Start_click()));
    this->connect(this->ui->pushButton_8, SIGNAL(released()), this,SLOT(button_Stop_click()));
    this->counter=10;
    this->ui->lcdNumber->display(counter);

These are the buttons

void Race::button_Start_click()
{
    counter--;
    this->ui->lcdNumber->display(counter);
}
void Race::button_Stop_click()
{

  terminate();
    break;
    this->ui->lcdNumber->display(counter);
}

Pl45m4

@Ruben12313

Hi,

first, you don't need to write this-> in front of every expression.
Like

// here
this->connect

// here
this->counter=10;

// or here
this->ui->lcdNumber->display(counter);

Without this everywhere the code looks a little cleaner.
You only need this when addressing "this" instance, like in the connect statement, where you want to connect to the current class and object.
And when dealing with two identical variables... one local, the other a member of "this" class (in a setter function, for example)
Then it's:

void setCounter(int counter)
{
    this->counter = counter;
}

Left-hand side your member, right-hand side the local variable that you pass in.
Without the this there, they have to have different names, or it won't work.

break;

What should the break; do there?
What is terminate() doing?

You said start_click() should increment the counter, but in there you are doing

counter--;

?

And for what are you planning to use a loop?
If you want to continuously increase or decrease the counter without clicking, you need a timer (QTimer)
Please explain what exactly you are trying to achieve.