default argument error

[reina]

why is qt forcing me to put a default argument here for img_path?
AvailableTile(QWidget* parent = 0,QString img_path);

my next question is,
is it only okay to modify the ui_mainwindow myself? because i need it to modify

[mrjj]

hi
what is AvailableTile ?
Seems it has a constructor that wants two arguments instead of the normal parent only.

ui_mainwindow is generated from the UI file by a program called moc.

If you edit it, your modifications will be gone next time it is regenerated.

Its far better to change stuff outside the file ,
like in mainwindows constructor
after
ui->setupUi ( this );

You can access any widget with ui->
so anything you can do in ui_mainwindow you can do here and it is not overwritten.

[Olivier Ronat]

In fact you must put the default arguments from right to left. To solve your problem you must write :
AvailableTile(QString img_path, QWidget* parent = 0);

[reina]

what is AvailableTile ?
AvailableTile is a constuctor from AvailableTile class.

AvailableTile(QWidget* parent = 0);
this default constructor doesnt have any problem.
**
You can access any widget with ui->
so anything you can do in ui_mainwindow you can do here and it is not overwritten**.
grass = new AvailableTile(centralWidget); // this is the generated code of ui_mainwindow
but i need it to be
grass = new AvailableTile("../Desktop/grass.png",centralWidget);

so how do i do that

[reina]

In fact you must put the default arguments from right to left. To solve your problem you must write :
can you explain it to me why?

[SGaist]

Hi,

Because it's a rule of C++, see here

[mrjj]

@reina

Perhaps AvailableTile has a function to set img_path after it has been constructed with the
default constructor ?

If not, you must create yourself and insert into the mainwindow.
You cannot get Creator to use the other constructor via the UI generator.

is AvailableTile your own class?