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Let's say I need to display a list of items. Each item contains a QPushButton an image and some text. When a user clicks on the button something should happen (ie I need to get the signal). What is the right way to implement this in Qt?

After some reading, I understand that if I use a QListWidget and QListWidgetItem, this can be achieved. I can subclass each QListWidgetItem according to my needs and set them in the list widget.

However, I also read that a more appropriate approach (the Model View approach) is to use a QlistView coupled with a QItemDelegate. But if I'm using QItemDelegate, it seems that I can only paint the widgets. How can I get the push button event?

Sorry for this huge post. I'm kind of confused about the whole concept of when to use a QListWidget / QListView.

Evan Zhao
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Mahadevan Sreenivasan
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2 Answers2

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QListWidget is essentially a customized version of QListView, designed for standard cases of list widgets, when all you're doing is just presenting image or text items in a list and the relationship with the underlying model is straightforward.

With QListWidget and its associated class QListWidgetItem you can e.g. insert and remove items very easily. But if you're inserting QPushButtons, then you can't use this so you might as well just use QListView and its (inherited) methods for setting the widget for a given index.

As for the signal, since you'll be creating the QPushButtons, just use 

QObject::connect(my_button, SIGNAL(clicked()),...)

to deal with that.

mtb
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Matt Phillips
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  • Thanks for your valuable input. I understand that using a QListView is the most light weight and preferred approach. I just need to display a list of 5 - 6 items. And I need icons and buttons inside each cell. I'd probably go with QListWidget and setIndexWidget for now as it seems to reduce the dev time. – Mahadevan Sreenivasan May 16 '11 at 06:17
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    Apparently you can use a custom widget on `QListWidgetItem`. See this thread: http://qt-project.org/forums/viewthread/17953 – mydoghasworms Nov 29 '13 at 05:37
  • "But if you're inserting QPushButtons, then you can't use this" This is completely incorrect. You can use buttons and what not inside a `QListWidgetItem` as long as you properly connect all the slots and signales after you create the item and then add it to your `QListWidget`. If you were enable to do that then you did something wrong. – rbaleksandar Feb 12 '16 at 19:10
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To differ from Matt's answer, it seems you can use your own widget on a QListWidgetItem, as pointed out in this post on qt-project.org: http://qt-project.org/forums/viewthread/17953.

This might be useful if you only have a few items to display and are not interested in the bother of cooking up a model class.

mydoghasworms
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