Moving QTreeWidgetItems between two QTreeWidgets

Christian Ehrlicher

@mrjj said in Moving QTreeWidgetItems between two QTreeWidgets:

so i wonder whats the actual difference ?

takeChild() returns the pointer to the item. removeChild() does not - it's a convenience function which nobody needs since the item leaks in 99% of the use cases then.

mrjj

@Christian-Ehrlicher
doh, too little coffe :)
Completely missed it had no return.
Thank you.

Ovidiu_GCO

@mrjj I tried to move an item, and its children by selecting them too, from "Drivers" to "Participants" using Drag&Drop but It moved all of them as parent-items.

Any ideas on how to move them as a "tree" (the parent should keep its children with it).

Ovidiu_GCO

@Christian-Ehrlicher I don't really understand your approach. I understood your "takeChild()" use over the "removeChild()", but I don't even manage to move the parent-item using the ">>" button, so I don't understand how could I do it.

Could you provide some code snippet or at least more insight over this problem?

Pl45m4

@Ovidiu_GCO

When you select a parent to move right, iterate through its childs and move them with "takeChild" to your TreeList on the right.

(You have to insert them, of course. "takeChild" returns a pointer to child item, as @Christian-Ehrlicher already said)

EDIT:
"takeChildren" returns a QList of ALL children. So you dont have to move them one by one.
You can add this QList after your parent with "insertChildren(index, QList)"

EDIT2:
Connect this with your ">>" and "<<" Button onClick-Event, get the current selected item (parent) and it should work :)

Im not able to test it atm (online with smartphone)

Ovidiu_GCO

@Pl45m4 My first problem is that I am not able to move the parent. I only managed to move it using Drag&Drop, but not using the button ">>".

Pl45m4

@Ovidiu_GCO

The Qt Doc says that all items are selectable, checkable... by default.
If you get your selected item when ">>" is clicked, it should be fine.

// same with move left  (<<) btn
connect(moveRightBtn, SIGNAL(clicked()), this, SLOT(moveItemFnct ());

// Your move fnct:
void moveItem()
{
   //Get current selected item and append to
// your list on the right

Actually there is a SIGNAL to get the clicked item + its column.
Check it out
http://doc.qt.io/qt-5/qtreewidget.html#itemPressed

Ovidiu_GCO

@Pl45m4 I had no doubt it should work, but it is not working. I can't even copy the parent-item to the "Participants" QTreeWidget

Pl45m4

@Ovidiu_GCO

I just tried it... (2 TreeWidgets with only two parent items each)

I can access the items and get their names and stuff but they don't appear in the second TreeWidget :(
Even the selection by mouseClick worked and I got the name / indices from each item by pressing the button.
Maybe we overlook something?! Some steps to copy to a TreeWidget or maybe the items lose required flags when you "export" the items and try to add them to a different TreeWidget?!

Maaz Momin

@Ovidiu_GCO Can you show the code you have written after changes mentioned.

Ovidiu_GCO

@Pl45m4 I know, I tried it too. I was reading a post on stackoverflow but I didn't understand all of it. As far as I understood, QTreeWidget is used for static-view and we should use QTreeView(since Qt 5), but I don't find the documentation very friendly and I am still trying to understand it.

Maybe we should switch to QTreeView?

Ovidiu_GCO

@Maaz-Momin At this moment, my code for the ">>" button is a work in-progress and I kinda messed it up, but now it looks like this:

QTreeWidgetItemIterator it(ui.driversList);

		while (*it) {
			if ((*it)->isSelected())
				ui.participantsList->addTopLevelItem((*it));
			++it;
		}

I tried to make it copy any selected item from "Drivers" to "Participants", but there is no change in the view.

I didn't try to use .takeChild() yet, because I didn't manage to move the parent using code, just by Drag&Drop.

SGaist

Hi,

Out of curiosity, why are you using a tree model ?

Ovidiu_GCO

@SGaist Honestly, I don't really know... This is my first project using Qt (or even C++ on a more serious project). I am not familiar with it or any other framework, for that matter.

It is a school project and I am trying to make it work so I can add it to my portofolio hoping that in the future I will become an intern with Qt and C++(and eventually a Junior Software Engineer).

So, I use it because it is the first widget that seemed to work for me.
I need to show some details about the drivers from the database and select a few of them to participate in a race.

I believe I could use also a QTableView(since there are not a lot of details beside the name) with a checkbox on the last column that would tell if the driver is a participant or not, but I am still trying to make it work with QTreeWidgets.

I am open to suggestions, if you have an idea that would be appropriate to a newbie like me.

jsulm

@Ovidiu_GCO Do you really need a tree structure? If not you could simply use QListWidget.

Ovidiu_GCO

@jsulm I have to display a driver, his car and some specs for it. I think I will try a QTableView/QTableWidget

mrjj

@Ovidiu_GCO
Hi
Would a driver have more than one car,
or could the the information be presented as one item ?
like
alt text

Ovidiu_GCO

@mrjj There could be more entries of the same driver with different cars, yes.

I will try the QTableWidget approach, but I already stepped in other problems with it. (I will make a new post since they are not connected).

Thank you all for your time and advices! ;)

mrjj

Hi
Ok, so it really is a tree/table structure.
-Driver
--Car
stats
--Car
Stats

But i do wonder when you then select a driver, all his cars should
also be shown in the other list or just one of the cars ? (used for that race)

I liked this info
https://wiki.qt.io/How_to_Use_QTableWidget

when starting using QTableWidget

jsulm

@Ovidiu_GCO As alternative you could use several list widgets:

On the left is a list of drivers
To the right side of the first list you have a second one: when you select a driver you put the cars of that driver into this list
More lists if needed...