[SOLVED]How to delete an item from the treeview by droping an item to pushbutton or to an group box

[Ratzz]

@mrjj
I tried this

#include <QDragMoveEvent>
#include <QDropEvent>
protected:
    void dragMoveEvent(QDragMoveEvent *event);
    void dropEvent(QDropEvent *event);

ui->pushButton_DeleteMinorFrame->setAcceptDrops(true);

void Window::dragMoveEvent(QDragMoveEvent *event)
{
    Window *source =qobject_cast<Window *>(event->source());
    if (source && source != this &&
            (event->answerRect().intersects(ui->pushButton_DeleteMinorFrame->geometry())))
    {
        event->acceptProposedAction();
    }
}

void Window::dropEvent(QDropEvent *event)
{
    event->setDropAction(Qt::MoveAction);
    event->accept();
}

But above does not work for me. Where did i miss??
Control does not come to these function dragMoveEvent/dropEvent when i drag and drop

[mrjj]

Hi you have to use the Dropbutton also.

That is why I though using Mainwindow would be easier.

Best way to do that is to use the promote feature.

1. save the code in a file called dropbutton.h
   (just to be safe, also create dropbutton.cpp as empty)
2. right click on your button you want to be a drop button.
   Select "Promote To..."
   In "Promoted classname" type
   DropButton
   (case Matters!)
   in
   header file : type
   dropbutton.h
   Then click "Add" and then Promote.
   Now when you run the program, the normal buttons becomes the DropButton.

[ClapCreative]

Thanks mates

[Ratzz]

@mrjj
Yes, i Tried you code which turns out to be a Dropbutton. How to implement it in my code ?

[mrjj]

@Ratzz
As I wrote in answer ?
Using the promote feature.
Which will runtime replace a normal button with the DropButton.
Or you can new a button you self
Like
Dropbutton *but=Dropbutton (this)
and insert into your window/layout.

[Ratzz]

@mrjj
Yes its working now fine..
I have group box adjacent to treeview. Can i implement the same to groupbox?

[mrjj]

@Ratzz
Super.
Well If you promote the GroupBox, there might be issue with
Parent. I have never tried it.
Try it :)
If it says funny stuff , just demote it to a groupbox again.

Else its pretty much the same, except new filename and new name.

#include <QGroupBox>
#include <QDragMoveEvent>

class DropGroupBox : public QGroupBox {
  Q_OBJECT
 public:
  explicit  DropGroupBox(QWidget* parent = 0) : QGroupBox(parent) {
    setAcceptDrops(true);
  }
 protected:
  void dragEnterEvent(QDragEnterEvent* event) {
    event->acceptProposedAction();
  }

  void dropEvent(QDropEvent* event) {
    event->setDropAction(Qt::MoveAction);
    event->accept();
  }
};

[Ratzz]

@mrjj
i promoted the group using Qpushbutton but not allow me to promote the GroupBox. so i added dropgroupBox.h and promoted it.
But its not working.

[mrjj]

@Ratzz
Hi
Something must gone wrong. maybe.
Tried it here and it does accept drops

https://www.dropbox.com/s/7bkqatzm6vt1kmz/promotedgb.zip?dl=0

[SGaist]

Out of curiosity… Why are you creating so many widgets that should allow to delete items from your view using dnd ? It doesn't feel very intuitive nor following the guidelines of major OSs

[Ratzz]

@mrjj
Yes your code is working . But do not know in my case its not working .
You have used Listwidget and i have used list view . Does it matters??

[Ratzz]

@SGaist
Yes , My treeview is in between listview and groupbox . even if the listview items are dragged to the pushbutton_delete its getting deleted. which in my case should not. what is the best way to do ??

[SGaist]

Implement it in one of the usual ways:

• React to the delete or backspace key
• Have a delete button that will delete the currently selected row/column etc.
• Have a dedicated column with e.g. a QPushButton to delete the row completely.

[Ratzz]

@SGaist
I already have a delete button which deletes entire row.

[Ratzz]

@mrjj
The code you shared is working (group box).

[mrjj]

@Ratzz
Ok. super.

[Ratzz]

@mrjj
But now i can drag items from treeview as well as listview to pushbutton and groupbox. But i do not want the user to allow listview items to dragged to pushbutton/groupbox

[mrjj]

@Ratzz
Hmm maybe you can check with
sender();
in dragEnterEvent
and if its the not a Treeview then reject the drop

like

QTreeView* theone= dynamic_cast<QTreeView*>(sender());
   if( theone!= NULL ) 
   { 
      event->acceptProposedAction();
   }

[Ratzz]

@mrjj
I do not have dragEnterEvent event yet! . we have a custom event using dropMimeData .

[mrjj]

@Ratzz
how does this custom event look like ?

and its not an options just to disable Drag from listview?