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Qt Designer Edit Signals Slots



I was going through the 'Getting started' section for Qt using VS2012 as my IDE, and I got stuck when I had to add a slot

See full list on doc.qt.io.

to a button. Apparently there is a bug when using the Visual Studio add-in, that the submenu
  1. The buddy concept is also used in Qt's model/view framework. Linking Labels to Buddy Widgets. To enter buddy editing mode, open the Edit menu and select Edit Buddies. This mode presents the widgets on the form in a similar way to signals and slots editing mode but in this mode, connections must.
  2. Alas, I do not see 'Edit Signals/Slots' in the Edit menu, nor does the F4 key do anything obvious besides putting this message on the bottom-left: 'Click widgets to change the tab order.' I am using Qt Designer 3.3.4 on i386 GNU/Linux.
Go to slot doesn't show up in a context menu in Qt Designer (see bug). Needless to say, I spent more than two hours trying to figure out how to get around this problem. The following is what I found:
Let's say you have a class called Notepad that has a quit button and you want to handle when the button is clicked. First create a private slot in the class definition in the header file - Notepad.h in this example. Slots
class Notepad : public QMainWindow
{
...
private slots:
public void on_quitButton_clicked();
...
}

Qt Designer Edit Signals Slots App


DesignerOn the Notepad.cpp add the following:
void Notepad::on_quitButton_clicked();
{
}
Note: from what I read it's good idea to follow the convention on_name_signal() for all your custom slots.

Now open your *.ui file with Qt Designer. At this point I tried using the Signal/Slot editor to add the slot to the button on the GUI. The 'custom' slot we wrote above however doesn't show up when you click the slot dropdown.
After scouring stackoverflow and the Qt forums I found a couple of ways to get the custom slot to show in the dropdown.

Qt Designer Edit Signals Slots Tool

  1. Go to Signal/Slots mode by pressing F4 on your keyboard.
  2. Click on the button so that it changes color.
  3. Left-click and drag it to the top of the main window.

4. This brings up the Configure Connection window
5. On the left pane select the Signal clicked()
6. On the right pane select Edit

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7.

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This brings yet another window, select the + button.

Qt Designer Edit Signals Slots Free


8. Enter the name of the custom slot, on_quitButton_clicked() in this case.
9. Click Ok and now you should be able to see the slot in the dropdown in Signal/Slot editor.

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Pretty tedious, but if you want to use Visual Studio as the IDE, this is what you will have to go through until someone fixes the bug, or you decide to use Qt Creator. If I keep finding issues like this by using Visual Studio I think I'll have to do to the latter.