QListWidgetItem subclass - Crash program in drag/drop

[estanisgeyer]

Hi guys,

I have two QListWidget and drag n drop is working perfectly. Instead of using the class QListWidgetItem for items, I created a subclass of QListWidgetItem, adding two methods that need a QAction to a store (action) and another to store an integer (idAct).

The problem is when I use the mouse to do the drag / drop, the integer returned is invalid. I already use the AddItem method that I created, which is the same as the drag / drop the mouse, I got the right result. How can I fix this? I'll post the code here so they can understand.

DLG_EditToolBar::DLG_EditToolBar(QWidget *parent)
		:QDialog(parent)
{
	ui.setupUi(this);
	m_activeList = new ListWidget;    // subclass QListWidget
	m_inactiveList = new ListWidget; // subclass QListWidget
 
	ui.gridLayoutAD->addWidget(m_inactiveList);
	ui.gridLayoutAT->addWidget(m_activeList);
	this->addAct(m_inactiveList);
 
	connect(ui.pushButton_Ad, SIGNAL(clicked()), this, SLOT(addItem()));
	connect(ui.pushButton_Rem, SIGNAL(clicked()), this, SLOT(removeItem()));
	connect(ui.pushButton_Up, SIGNAL(clicked()), this, SLOT(upItem()));
	connect(ui.pushButton_Down, SIGNAL(clicked()), this, SLOT(downItem()));
	connect(ui.pushButton_OK, SIGNAL(clicked()), this, SLOT(ok()));
	connect(ui.comboBox_BarraFerramentas, SIGNAL(currentIndexChanged(int)), this, SLOT(changeBF(int)));
}
 
DLG_EditToolBar::~DLG_EditToolBar()
{
 
}
 
void DLG_EditToolBar::changeBF(int t)
{
	if (t > 0)
	{
		listItem_toolp.clear();              // type QList<QListWidgetItem *>
		int r = m_activeList->count();
		for (int i = 0; i < r; i++)
		{
			listItem_toolp.append(m_activeList->takeItem(0));
		}
 
		m_activeList->clear();
 
		for (int i = 0; i < listItem_toolaux.count(); i++)
		{
			m_activeList->addItem(listItem_toolaux.at(i));
		}
	}
	else
	{
		listItem_toolaux.clear();          // type QList<QListWidgetItem *>
		int r = m_activeList->count();
		for (int i = 0; i < r; i++)
		{
			listItem_toolaux.append(m_activeList->takeItem(0));
		}
 
		m_activeList->clear();
		for (int i = 0; i < listItem_toolp.count(); i++)
		{
			m_activeList->addItem(listItem_toolp.at(i));
		}
	}
}
 
void DLG_EditToolBar::addAct(QListWidget *p)
{
	Item *item;
	for (int i = 0; i < Actions::listTrAction()->count(); i++)
	{
		item = new Item(Actions::listTrAction()->at(i), Actions::listTrAction()->at(i)->id(), p);
	}
}
 
void DLG_EditToolBar::addItem()
{
	m_activeList->addItem(m_inactiveList->takeItem(m_inactiveList->currentRow()));
}
 
void DLG_EditToolBar::ok()
{
	foreach (QListWidgetItem *i, listItem_toolp)
	{
               // here is the problem, it works when using the function AddItem, 
               // but when it does not drag n drop with the mouse.
		qDebug() << static_cast<Item *>(i)->idAct();
 
 
		//MainWindow::toolbar->addAction(static_cast<Item *>(i)->action());
	}
 
	foreach (QListWidgetItem *i, listItem_toolaux)
	{
		//MainWindow::toolbarAux->addAction(static_cast<Item *>(i)->action());
	}
 
	this->accept();
}

DLG_EditToolBar::DLG_EditToolBar(QWidget *parent)
		:QDialog(parent)
{
	ui.setupUi(this);
	m_activeList = new ListWidget;    // subclass QListWidget
	m_inactiveList = new ListWidget; // subclass QListWidget

	ui.gridLayoutAD->addWidget(m_inactiveList);
	ui.gridLayoutAT->addWidget(m_activeList);
	this->addAct(m_inactiveList);

	connect(ui.pushButton_Ad, SIGNAL(clicked()), this, SLOT(addItem()));
	connect(ui.pushButton_Rem, SIGNAL(clicked()), this, SLOT(removeItem()));
	connect(ui.pushButton_Up, SIGNAL(clicked()), this, SLOT(upItem()));
	connect(ui.pushButton_Down, SIGNAL(clicked()), this, SLOT(downItem()));
	connect(ui.pushButton_OK, SIGNAL(clicked()), this, SLOT(ok()));
	connect(ui.comboBox_BarraFerramentas, SIGNAL(currentIndexChanged(int)), this, SLOT(changeBF(int)));
}

DLG_EditToolBar::~DLG_EditToolBar()
{

}

void DLG_EditToolBar::changeBF(int t)
{
	if (t > 0)
	{
		listItem_toolp.clear();              // type QList<QListWidgetItem *>
		int r = m_activeList->count();
		for (int i = 0; i < r; i++)
		{
			listItem_toolp.append(m_activeList->takeItem(0));
		}

		m_activeList->clear();

		for (int i = 0; i < listItem_toolaux.count(); i++)
		{
			m_activeList->addItem(listItem_toolaux.at(i));
		}
	}
	else
	{
		listItem_toolaux.clear();          // type QList<QListWidgetItem *>
		int r = m_activeList->count();
		for (int i = 0; i < r; i++)
		{
			listItem_toolaux.append(m_activeList->takeItem(0));
		}

		m_activeList->clear();
		for (int i = 0; i < listItem_toolp.count(); i++)
		{
			m_activeList->addItem(listItem_toolp.at(i));
		}
	}
}

void DLG_EditToolBar::addAct(QListWidget *p)
{
	Item *item;
	for (int i = 0; i < Actions::listTrAction()->count(); i++)
	{
		item = new Item(Actions::listTrAction()->at(i), Actions::listTrAction()->at(i)->id(), p);
	}
}

void DLG_EditToolBar::addItem()
{
	m_activeList->addItem(m_inactiveList->takeItem(m_inactiveList->currentRow()));
}

void DLG_EditToolBar::ok()
{
	foreach (QListWidgetItem *i, listItem_toolp)
	{
               // here is the problem, it works when using the function AddItem, 
               // but when it does not drag n drop with the mouse.
		qDebug() << static_cast<Item *>(i)->idAct();


		//MainWindow::toolbar->addAction(static_cast<Item *>(i)->action());
	}

	foreach (QListWidgetItem *i, listItem_toolaux)
	{
		//MainWindow::toolbarAux->addAction(static_cast<Item *>(i)->action());
	}

	this->accept();
}

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Thanks,

Marcelo E. Geyer

[wysota]

Can you show us the code using for setting the data for the drag? I mean the mimeData() method from your widget.