About the ui object and what it holds
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Hey guys , i'm using the newest qt creator , and i'm new to this I got 3 question , if you guys can help me with it ^^
1- the ui object , when I try to access classes , what does it include ? and can I access stuff without the ui object ?
2- when I try to do this " ui->pushbutton->settext(...);
is this going to set all push buttons to the name that I've put in the arguments ?3- what's the difference between renaming it in the edit widget and the function above ?
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HI,
Welcome to Qt-project forum.
If using designer the ui object holds all your GUI elements that you created with designer. The MOC compiler will generate a mainwindow_ui.h file in the background that will construct a ui class object.
In the beginning of your main window class you will see @ui(new Ui::MainWindow)@ which is the same as: Setup the pointer ui to the constructor of the Ui::MainWindow class
The @ui->setupUi(this)@ will allocate all needed memory for the GUI elements.
1: Without the ui object you can't access your GUI elements!!
2: No, it will only set the text of the pushButton with the objectName: pushButton. In designer the next pushButton will get ObjectName: pushButton_2 and so on and on. It is my recommendation to rename them
3: Renaming the widget in designer is compile time, setting the text in the setText() function is runtime, but the result is the same. -
Thanks man , so about the pushbutton , it's all depends on the order ? for example if I put two pushbutton , and called settext("ok"), and the next one settext(" not ok ") , the first one will get the name " ok " and second " not ok " ? and we can apply it on things beside settext ?
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ah , I just tried adding a second one and there was " pushButton_2 " :D
thank you ^^
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;-) Like in any C++ class you may not have two the same identifiers
What you could do, but that might be a bit to advanced for now is to get the ui pointer and get all children (QObject function) and do a dynamic cast to a QPushButton, if succesfull do the setText function with a counter value. If you really need to do it run time. -
Thanks man , I'm really upset , when I tried to create a simple program I couldn't have done it , it seems that it still confuses me I just finished learning about signal and slot :(
is there a website that gives you a simple problems that you can solve ?
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This forum is a good start if you encounter problems. There are more then enough guys here to help you.
There is a 'how to learn Qt' doc on this site somewhere if you need some assistance. -
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Yes.!! U can access the all the widgets or stuffs with out using Ui. but for that u have to do some changes in header file as well as .cpp file.
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No. It do not set all push buttons to the name that u've put in the arguments
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The difference between renaming and settext() method is that when u use rename . It change name of the object but settext() just use to write any text on it. So u can write same text on two buttons but name of the two buttons must be different.
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When U will write "Ui->" then it automatically show the name of the all objects.
