I have a (very simple yet) QTreeView showing some rows:
m_cameraModel = new QStandardItemModel(this);
QSortFilterProxyModel* cameraProxyModel = new QSortFilterProxyModel(this);
cameraProxyModel->setSourceModel(m_cameraModel);
ui.CameraTreeView->setModel(cameraProxyModel);
m_cameraModel->appendRow(new QStandardItem("Panavision"));
m_cameraModel->appendRow(new QStandardItem("Panaflex"));
Here I want to disable the first row "Panavision" so that it is still visible but can't be selected any more and is somehow greyed-out so that the user can see this entry is not active.
May be this is some kind of beginner-question, but how can this be done?
Thanks!
I would try to do that in the following way:
// Get item that corresponds to the first row
QStandardItem *item = m_cameraModel->item(0, 0);
// Disable the item.
item->setFlags(Qt::NoItemFlags);
You'd want to use the QItemDelegate class, which allows you to disable the row you want to amongst other things. There's a good question here on StackOverflow that shows how to do a very basic example: How to set a delegate for a single cell in Qt item view?
Related
I have a QTableWidget table with more than 2000 rows. When i add QToolButton "Remove" in each row, it become a little bit slow). Why table become slow, buttons ui or signal mapper? How can i speed up my table, maybe replace buttons with something else or connect signals in other way?
My code for buttons:
// mapper for remove buttons
QSignalMapper* signalMapper = new QSignalMapper(this);
connect(signalMapper, SIGNAL(mapped(int)), this, SLOT(RemoveString(int)), Qt::UniqueConnection);
than for each row:
//remove button
QToolButton* remove_button = new QToolButton(this);
remove_button->setText("Remove");
signalMapper->setMapping(remove_button, index);
connect(remove_button, SIGNAL(clicked()), signalMapper, SLOT(map()), Qt::UniqueConnection);
ui->locale_table->setCellWidget(index, 3, remove_button);
As vahancho said you will want an item delegate. Item delegates simply display the data and information in a certain way. It mainly paints the item to look like what you want, so it doesn't necessarily create a whole widget. You will probably want to use a styled item delegate. http://qtadventures.wordpress.com/2012/02/04/adding-button-to-qviewtable/ This should have all of the information you need.
You set the item delegate to the widget with the QTableWidget methods setItemDelegate, setItemDelegateForColumn, setItemDelegateForRow.
I'm trying to do something that seems like it should be very simple, but the more I look into it I wonder if it's a Qt bug.
So, I have a QTableView that has columns that can be shown/hidden as the user likes. After I initialize the table, I call a custom restoreColumns() method that hides the columns (using QTableView::hideColumn()) that the user had hidden the last time the GUI was open.
The problem then comes when the user tries to show the columns that were hidden by the user the last time the GUI was ran. The appropriate signal/slot gets called and run through but for some reason the QTableView isn't updating to display the column.
What's weird is that any column that is already displayed (was not hidden by the user the last time the GUI was ran) has no problems with getting hidden/shown.
Any thoughts? Thanks!
Here's how I initialize the table...
m_tableModel = new mytablemodel();
m_tableView = new mytableview();
m_tableView->setItemDelegate(m_tableDelegate);
m_tableView->setModel(m_tableModel);
Meat of restoreColumns() method:
for (int i=0; i<horizontalHeader()->count(); i++) {
// load size to restore previous width
...
horizontalHeader()->resizeSection(i, width); // restore width
// load previous column position
...
// restore column order
int currentVisualIndex = horizontalHeader()->visualIndex(i);
if (currentVisualIndex != visualIndex)
horizontalHeader()->moveSection(currentVisualIndex, visualIndex);
// load previous hidden/shown state
...
if (columnHidden) {
hideColumn(i);
} else {
showColumn(i);
}
}
Below is some sample code to show/hide one of the columns.
void mytableview::showAColumn(bool checked) {
// mytableview is a subclass of qtableview
if (checked)
showColumn(COLUMN_A); // COLUMN_A is an enum for the column
else
hideColumn(COLUMN_A);
}
Which is connected to a QAction that can be accessed from the Menu and Context Menu of the QHeaderView of the QTableView.
connect(action, SIGNAL(toggled(bool)), this, SLOT(showAColumn(bool)));
When you are loading the previous width of the hidden columns, the width that was saved was 0.
So, when resizing the column make sure that the width is greater than 0.
Do this and then the columns will show/hide as expected.
I want to add a QPushButton inside ListItm, so I have implemented the code as given below. But the button comes in the middle of the list, actually I want it at the lower end of the list item. How is it possible. Also that button click event is not working. Actually I want to disable the item click event directly and by clicking the button inside the QListWidgetItem, I want to enable the item click event. But I am not able to perform this operation. How to do this? I have used the following code snippet:
list=new QListWidget(this);
// list->setStyleSheet("* { background-color:rgb(0,0,0); padding: 10px ; color:rgb(255,255,255)}");
list->setGeometry(0,61,360,475);
list->setSortingEnabled(true);
//connect(list,SIGNAL(itemClicked(QListWidgetItem*)),this,SLOT(ItemClicked(QListWidgetItem*)));
item=new QListWidgetItem();
item->setIcon(QIcon(":/images/Icon.png"));
item->setText("Item1");
item->setSizeHint(QSize(80,80));
item->setBackgroundColor(QColor(200,255,100));
list->addItem(item);
QPushButton *but = new QPushButton(">");
but->setMaximumSize(50,80);
but->setFlat(true);
// but->setGeometry(QRect(500,100,100,100));
but->setStyleSheet("background: transparent; border: none");
QHBoxLayout *layout= new QHBoxLayout();
layout->addWidget(but);
QWidget *widget = new QWidget();
widget->setLayout(layout);
item->setSizeHint(widget->sizeHint());
list->setItemWidget(item, widget);
connect(but, SIGNAL(clicked()), this, SLOT(ItemClicked()));
#if defined(Q_WS_S60)
list->showMaximized();
#else
list->show();
#endif
ItemClicked()
{
int Index = list->currentIndex().row();//Always getting this Index as -1
}
Please have a look on the above code and provide your suggestions.
Thanks...
Reconsider using QPushButton as "click" handle for listwidget. There is a reason why QListWidgetItem is not QObject. QObjects are somewhat "heavy", because of all metadata structures they hold. That's why Qt is not using QObjects in data oriented lists like QListWidgetItem.
About your problem. You will get always -1, until you won't select item by NOT clicking on it's button part, but on item. That's because QPushButton is taking focus away, and doesn't pass click event down to QListWidgetItem. So it may even happend, that you select item with idx = 3, click on button of item with idx = 1 and will get in your slot idx 3.
Actualy, as for me you're performing your whole taks totaly wrong. First of all, I would use QTreeWidget, for multicolumns. Secondly, I would "implement" custom item delegate, to draw "button", and I would set it as delegate for column 1. Then I would catch "click event" normally, but react only for column 1.
| column 0 (actual data exposition) | column 1 (custom delegate, draw button)
I have a QGroupBox with a couple of QRadioButtons inside of it and in certain cases I want all radio buttons to be unchecked. Seems that this is not possible when a selection has been made. Do you know of a way I could do this or should I add a hidden radiobutton and check that onen to get the desired result.
You can achieve this effect by temporarily turning off auto exclusivity for all your radio buttons, unchecking them, and then turning them back on:
QRadioButton* rbutton1 = new QRadioButton("Option 1", parent);
// ... other code ...
rbutton1->setAutoExclusive(false);
rbutton1->setChecked(false);
rbutton1->setAutoExclusive(true);
You might want to look at using QButtonGroup to keep things tidier, it'll let you turn exclusivity on and off for an entire group of buttons instead of iterating through them yourself:
// where rbuttons are QRadioButtons with appropriate parent widgets
// (QButtonGroup doesn't draw or layout anything, it's just a container class)
QButtonGroup* group = new QButtonGroup(parent);
group->addButton(rbutton1);
group->addButton(rbutton2);
group->addButton(rbutton3);
// ... other code ...
QAbstractButton* checked = group->checkedButton();
if (checked)
{
group->setExclusive(false);
checked->setChecked(false);
group->setExclusive(true);
}
However, as the other answers have stated, you might want to consider using checkboxes instead, since radio buttons aren't really meant for this sort of thing.
If you're using QGroupBox to group buttons, you can't use the setExclusive(false) function to uncheck the checked RadioButton. You can read about it in QRadioButton section of QT docs. So if you want to reset your buttons, you can try something like this:
QButtonGroup *buttonGroup = new QButtonGroup;
QRadioButton *radioButton1 = new QRadioButton("button1");
QRadioButton *radioButton2 = new QRadioButton("button2");
QRadioButton *radioButton3 = new QRadioButton("button3");
buttonGroup->addButton(radioButton1);
buttonGroup->addButton(radioButton2);
buttonGroup->addButton(radioButton3);
if(buttonGroup->checkedButton() != 0)
{
// Disable the exclusive property of the Button Group
buttonGroup->setExclusive(false);
// Get the checked button and uncheck it
buttonGroup->checkedButton()->setChecked(false);
// Enable the exclusive property of the Button Group
buttonGroup->setExclusive(true);
}
You can disable the exclusive property of the ButtonGroup to reset all the buttons associated with the ButtonGroup, then you can enable the Exclusive property so that multiple button checks won't be possible.
I have a QTableView and a QStandardItemModel. Is there have a column can contain checkboxes that are user editable without using delegates or using the abstract model classes? It is not that I can't do it, I just want to minimize the code, I would find it overkill for simple check boxes.
By using model.setData(index, Qt::Unchecked,Qt::CheckStateRole) this creates the checkbox but it is not user editable (text beside checkbox is).
I used modelTX.setData(index, FALSE) but this creates a combo box containing True and False.
I'll try setItemData.
pls, check if the following example would work for you:
QStandardItemModel* tableModel = new QStandardItemModel();
// create text item
tableModel->setItem(0, 0, new QStandardItem("text item"));
// create check box item
QStandardItem* item0 = new QStandardItem(true);
item0->setCheckable(true);
item0->setCheckState(Qt::Checked);
item0->setText("some text");
tableModel->setItem(0, 1, item0);
// set model
ui->tableView->setModel(tableModel);
hope this helps, regards