I was trying to select item "leaf2" from QComboBox with QTreeView in the below code.
I just want to select items with no child from text by code. (if there is a child, it won't be selectable)
How can I select item or index with no child item?
Can anyone help me with this problem?
Thank you.
void Main::initView()
{
QStandardItemModel *model = new QStandardItemModel;
QStandardItem *root_item = model->invisibleRootItem();
// Build Model Items
QStandardItem *node_item = NULL;
node_item = new QStandardItem("Node");
node_item->setFlags(Qt::ItemIsEnabled);
root_item->appendRow(node_item);
QStandardItem *leaf_item = new QStandardItem("leaf1");
leaf_item ->setFlags(Qt::ItemIsEnabled | Qt::ItemIsSelectable);
node_item->appendRow(leaf_item );
leaf_item = new QStandardItem("leaf2");
leaf_item ->setFlags(Qt::ItemIsEnabled | Qt::ItemIsSelectable);
node_item->appendRow(leaf_item );
// Set Model to TreeViewComboBox
ui.cb_treevew->setModel(model);
ui.cb_treeview->setCurrentIndex(0); // "Node" is selected.
ui.cb_treeview->setCurrentIndex(1); // Nothing is selected.
ui.cb_treeview->setCurrentIndex(2); // Nothing is selected.
ui.cb_treeview->setCurrentIndex(3); // Nothing is selected.
}
Here is my code for CTreeViewComboBox.
CTreeViewComboBox::CTreeViewComboBox(QWidget *parent) : QComboBox(parent)
{
QTreeView* treeView = new QTreeView(this);
treeView->setEditTriggers(QTreeView::NoEditTriggers);
treeView->setSelectionBehavior(QTreeView::SelectRows);
treeView->setSelectionMode(QTreeView::SingleSelection);
treeView->setItemsExpandable(true);
treeView->header()->setVisible(false);
treeView->setWordWrap(true);
setView(treeView);
}
PS: I tried to select items as following, but not working. :(
ui.cb_treeview->treeView()->setCurrentIndex(getModelIndexFromText("leaf2"));
If the nodes with children will never have the same text with the nodes without children then the following method is appropriate.
QModelIndexList modelIndexes = model->match(
model->index(0, 0),
Qt::DisplayRole,
"leaf2",
-1,
Qt::MatchRecursive);
QModelIndex index = modelIndexes.first();
ui.cb_treeview.setRootModelIndex(index.parent());
ui.cb_treeview.setCurrentIndex(index.row());
On the other hand, if the nodes with children can have the same text as the nodes without children, you should use the following method.
QModelIndexList modelIndexes = model->match(
model->index(0, 0),
Qt::DisplayRole,
"leaf2",
-1,
Qt::MatchRecursive);
QModelIndexList::iterator tstIt = std::find_if(modelIndexes.begin(),
modelIndexes.end(),
[] (const QModelIndex & index) {
return !index.model()->hasChildren(index);
});
ui.cb_treeview.setRootModelIndex(tstIt->parent());
ui.cb_treeview.setCurrentIndex(tstIt->row());
In both cases I am assuming that nodes without children always have different texts. If nodes without children match the name, choose one of them.
Related
I am creating a UI with QTreeView representing list of items(which may or may not have children) and displaying corresponding widget on right side using QStackedWidget. Previously the behaviour of my data or the list of items mentioned above was flat, hence I was using QListView but when the data had to have children I replaced the QListView with QTreeView so I can add children as well. I have achieved the above in the following manner:
for(std::vector<AWidget* >::iterator it=widgets.begin(); it!=widgets.end(); ++it)
{
AWidget* w = *it;
QStandardItem *parent = new QStandardItem(w->Name());
model->setItem(i, 0, parent);
QWidget *PageWidget = w->getWidget();
QScrollArea * pScrollArea = new QScrollArea();
pScrollArea->setWidget(PageWidget);
m_ui.AStackedWidget->addWidget(pScrollArea);
if(!w->hasChildren())
{
std::vector<AWidget*> children = w->getChildren();
for(std::vector<AWidget*>::iterator iChild=children.begin(); iChild!=children.end(); ++iChild)
{
AWidget* childWidget = *iChild;
QStandardItem *child = new QStandardItem(childWidget->Name());
parent->appendRow(child);
QWidget *childPageWidget = childWidget->getWidget();
QScrollArea * pChildScrollArea = new QScrollArea();
pChildScrollArea->setWidget(childPageWidget);
pChildScrollArea->setWidgetResizable(true);
m_ui.AStackedWidget->addWidget(pChildScrollArea);
}
}
i++;
}
m_ui.ATreeView->setEditTriggers(QAbstractItemView::NoEditTriggers);
m_ui.ATreeView->setTabKeyNavigation(true);
m_ui.ATreeView->setModel(model);
QModelIndex index = m_ui.ATreeView->model()->index(0,0);
QItemSelectionModel * selModel = m_ui.ATreeView->selectionModel();
if(selModel)
{
connect(selModel, SIGNAL( currentChanged(const QModelIndex &, const QModelIndex &) ), this , SLOT(slotOptionSelectedForChangeUI(const QModelIndex & )) );
selModel->select(index,QItemSelectionModel::Select);
}
slotOptionSelectedForChangeUI(index);
Definition of slotOptionSelectedForChangeUI() is as follows:
void slotOptionSelectedForChangeUI(const QModelIndex & indx)
{
int rowNum = indx.row();
if(m_ui.AStackedWidget)
m_ui.AStackedWidget->setCurrentIndex(rowNum);
}
For eg: following is the view:
-A -> widget1
-B -> widget2
-C -> widget3
-D -> widget4
-E -> widget5
-E1 -> widget6
-E2 -> widget7
-E3 -> widget8
-E4 -> widget9
-E5 -> widget10
-E6 -> widget11
- E7 -> widget12
A,B,C,D,E show correct corresponding widgets on the right side in the QStackedWidget. However E1, E2, E3, E4,E5,E6,E7 show widgets widget1,2,3,4,5,6,7 respectively. This means index of E1 starts again from 0 and stacked widget shows widget0 for index 0 and so on. How should E1-E7 be mapped with widget6-12 so that proper widgets are displayed on the right side stacked widget?
The proper way of doing this is by not using a QStackedWidget, but only displaying one. To do this, all you have to do is:
Add the widget to the item using QStandardItem::setData
In the ui, instead of a QStackedWidget, just use a simple QWidget (with a horizontal/vertical layout without margins)
Connect the selection model index changed signal to a slot that removes all children from the simple widget, and adds the one stored with the item. You can retrieve it by using the QStandardItem::data function (or the models data function)
Here a minimal example of those steps:
#define MyRole Qt::UserRole + 42
//...
//adding the item
AWidget* w = *it;
QStandardItem *parent = new QStandardItem(w->Name());
parent->setData(QVariant::fromValue(w), MyRole);
model->setItem(i, 0, parent);
//...
//the index changed slot
void slotOptionSelectedForChangeUI(const QModelIndex & indx)
{
AWidget *w = model->data(index, MyRole).value<AWidget*>();//will internally call QStandardItem::data
//remove old children
QList<QWidget*> children = m_ui.containerWidget->findChildren<QWidget*>(QString(), Qt::FindDirectChildrenOnly);
foreach(QWidget *child, children)
child->deleteLater();
//add the new one
QWidget *PageWidget = w->getWidget();
ScrollArea * pScrollArea = new QScrollArea(m_ui.containerWidget);
pScrollArea->setWidget(PageWidget);
m_ui.containerWidget->layout()->addWidget(pScrollArea);
}
I have a QListview where I have set a model. The model contains the QList. Now I want to get the contents of QListview on clicking the item. But I don't know how to do this? Through some tutorials I followed I am able to get two items appear in the QListview as follows. But I dont know how to make it work?? Please anyone help. The code which I am working as follows.
listviewmodel =new QListView;
listviewmodel->setModel( createModel() );
listviewmodel->setViewMode(QListView::IconMode);
listviewmodel->setIconSize(QSize(size().width()/8, size().height()/8));
connect(listviewmodel,SIGNAL(clicked(const QModelIndex)),this,SLOT(ItemClicked(QModelIndex)));
QAbstractItemModel *MainWindow::createModel()
{
QStandardItemModel *model = new QStandardItemModel();
QList<QStandardItem *> listItem;
QStandardItem *item2 = new QStandardItem();
item2->setIcon(QIcon(QPixmap::fromImage(qimages2)));
listItem << item2;
QStandardItem *item1 = new QStandardItem();
item1->setIcon(QIcon(QPixmap::fromImage(qimages1)));
listItem << item1;
model->appendColumn(listItem);
return model;
}
void MainWindow::ItemClicked (QModelIndex index )
{
textEdit->setText(index.data().toString());
}
I checked your code in QtCreator and it works as you described. So what is the problem? Are you getting some errors? Maybe did you not put declaration of ItemClicked(QModelIndex) below the public slots:? Are you sure that connect returns true? Try to check it:
bool success = connect(listviewmodel,SIGNAL(clicked(const QModelIndex)),this,SLOT(ItemClicked(QModelIndex)));
Q_ASSERT(success);
EDIT: If you want to display only icons at QListView and get some text informations after clicking on specified item, you can do it in the following way:
item2->setIcon(QIcon(QPixmap::fromImage(qimages2)));
item2->setData("informations about item2", Qt::UserRole);
(...)
void MainWindow::ItemClicked (QModelIndex index )
{
QString data = index.data(Qt::UserRole).value<QString>();
ui->textEdit->setText(data);
}
I have derived the class QTreeWidget and creating my own QtPropertyTree. In order to populate the tree with widgets (check boxes, buttons, etc) I am using the following code:
// in QtPropertyTree.cpp
QTreeWidgetItem topItem1 = new QTreeWidgetItem(this);
QTreeWidgetItem subItem = new QTreeWidgetItem(this);
int column1 = 0
int Column2 = 1;
QPushButton myButton = new QPushButton();
this->setIndexWidget(this->indexFromItem(this->subItem,column1), myButton);
QCheckBox myBox = new QCheckBox();
this->setIndexWidget(this->indexFromItem(this->subItem,column2), myBox);
This works fine, but the problem is that i want to avoid using the "indexFromItem" function since it is protected, and there are other classes that are populating the tree and need access to that funcion. Do you know any alternative to using that function?
You can try to use your QTreeWidget's model (QAbstractItemModel) to get the right index by the column and row numbers:
// Row value is 1 because I want to take the index of
// the second top level item in the tree.
const int row = 1;
[..]
QPushButton myButton = new QPushButton();
QModelIndex idx1 = this->model()->index(row, column1);
this->setIndexWidget(idx1, myButton);
QCheckBox myBox = new QCheckBox();
QModelIndex idx2 = this->model()->index(row, column2);
this->setIndexWidget(this->indexFromItem(idx2, myBox);
UPDATE
For sub items, the same approach can be used.
QModelIndex parentIdx = this->model()->index(row, column1);
// Get the index of the first child item of the second top level item.
QModelIndex childIdx = this->model()->index(0, column1, parentIdx);
The obvious solution is to de-protect indexFromItem like this:
class QtPropertyTree {
...
public:
QModelIndex publicIndexFromItem(QTreeWidgetItem * item, int column = 0) const
return indexFromItem (item, column) ;
}
} ;
How can I implement this code I have for a qTreeWidget for a qTreeView?
for (const auto & i : names) {
QTreeWidgetItem * item = new QTreeWidgetItem(ui->treeWidget);
item->setText(0, QString::fromStdString(i));
ui->treeWidget->addTopLevelItem(item);
const std::unordered_map<std::string, double> map = m_reader.getMapFromEntry(i);
for (const auto & j : map) {
QTreeWidgetItem * item2 = new QTreeWidgetItem();
item2->setText(0,QString::fromStdString(j.first));
item2->setText(1,QString::number(j.second));
item->addChild(item2);
}
}
I have a model and a treeView, like this:
m_model = new QStandardItemModel(m_reader.getAllNames().size(),2,this);
ui->treeView->setModel(m_model);
I tried this, but that only shows one column:
QStandardItem * parentItem = m_model->invisibleRootItem();
for (const auto & i : names) {
QStandardItem * item = new QStandardItem(QString::fromStdString(i));
parentItem->appendRow(item);
const std::unordered_map<std::string, double> map = m_reader.getMapFromEntry(i);
for (const auto & j : map) {
QList<QStandardItem *> rowItems;
rowItems << new QStandardItem(QString::fromStdString(j.first));
rowItems << new QStandardItem(QString::number(j.second));
item->appendRow(rowItems);
}
}
With the treeWidget, I had so set the columnCount, like this:
ui->treeWidget->setColumnCount(2);
But treeView does not have a method like this.
So, to summarize: How can I implement a TreeView with more than one column?
EDIT:
To clarify, I want something like this:
|-A
| |-B-C
| |-D-E
where A is the parent and B,C,D,E the children, with B,D being in column 0 and C,E in column 1.
Hope this helps!
To support multiple columns, the model must contain data for multiple columns.
So in some sense, columns are a property of the model, not the view. Views then can decide to hide or rearrange certain columns (For example, a QListView always only shows the first column, while one can hide or reorder columns in a QTableView).
As you use QStandardItemModel, its documentation should give a few hints how to create multiple columns.
E.g., look at this example from the documentation:
QStandardItemModel model(4, 4);
for (int row = 0; row < 4; ++row) {
for (int column = 0; column < 4; ++column) {
QStandardItem *item = new QStandardItem(QString("row %0, column %1").arg(row).arg(column));
model.setItem(row, column, item);
}
}
It creates a model with 4 initial rows and columns each, and then fills it with items via setItem().
Alternatively, you can pass a list of items to QStandardItemModel::appendRow(), with an item for each column:
QList<QStandardItem*> items;
items.append(new QStandardItem(tr("One"));
items.append(new QStandardItem(tr("Two"));
model->appendRow(items);
This adds a new row with "One' in the first column and "Two" in the second. For even more ways to deal with multiple columns, see the QStandardItemModel docs.
Note: QTreeView expects the same number of columns on all levels of the hierarchy, so one should fill rows with empty items for the unused columns if need be.
Just an addition to answer by Frank Osterfeld:
QTreeView displays all columns of subtables inserted into top level QStandardItems. You just have to "force" it to show additional columns by inserting dummy QStandardItems into top-level table. Example:
QStandardItemModel *objectTreeModel = new QStandardItemModel(NULL);
QStandardItem *mainItem = new QStandardItem(tr("Main Item"));
QStandardItem *subItem1 = new QStandardItem(tr("Sub-Item 1"));
QStandardItem *subItem2 = new QStandardItem(tr("Sub-Item 2"));
mainItem->appendRow(QList<QStandardItem *>() << subItem1 << subItem2);
QStandardItem *dummyItem = new QStandardItem();
objectTreeModel->appendRow(QList<QStandardItem *>() << mainItem << dummyItem );
Now you will be able to see 2 columns and if you expand mainItem, both subitems will be visible.
After reading some examples I am still missing here something.
I have Qtreeview for view and QStandardItemModel for the data interface, also using QSortFilterProxyModel subclass but I don't know if its relevant.
This is my logic:
First I create the model with the QWidget as the parent:
QStandardItemModel m_model = new QStandardItemModel(0,4,parent);
then setSourceModel(m_model) for the widget
Set the treeview with QSortFilterProxyModel. something like this:
GroupProxyModel = new GroupSortFilterProxyModel;
GroupProxyModel->setDynamicSortFilter(true);
setSourceModel(createSubjectModel(parent));
ui.treeView_mainwindow->setModel(GroupProxyModel);
ui.treeView_mainwindow->setSortingEnabled(true);
Then later I fill the first row like this:
QList<QStandardItem *> items;
items.insert(0,new QStandardItem("Test 0"));
items.at(0)->setEditable(false);
m_model->insertRow(0,items);
Until now every thing working fine and I see the row with the data. But when I like to
add child to the row like this:
QModelIndex parentQModelIndex = m_model->item(0,0)->index();
m_model->insertRows(0,1,parentQModelIndex);
m_model->insertColumns(0,1,parentQModelIndex);
QModelIndex indexB = m_model->index(0, 0, parentQModelIndex);
m_model->setData(indexB,"Child test",Qt::DisplayRole);
But I don't see the child, why?
That's not how QStandardItemModel works - to add a child, call appendRow(s)/insertRow(s) on the parent QStandardItem:
QStandardItem* child = new QStandardItem( tr("Child test") );
...
QStandardItem* parentItem = m_model->item( 0, 0 );
parentItem->appendRow( child );