Tree Model Completer Example▲
Similar to the https://, we provide https:// objects to enable selection for completion mode and case sensitivity, as well as a https:// for wrap completions.
The Resource File▲
The contents of the TreeModelCompleter is read from treemodel.txt. This file is embedded within the treemodelcompleter.qrc resource file, which contains the following:
<!DOCTYPE RCC><RCC version="1.0">
<qresource prefix="/">
<file>resources/treemodel.txt</file>
</qresource>
</RCC>TreeModelCompleter Class Definition▲
The TreeModelCompleter is a subclass of https:// with two constructors - one with parent as an argument and another with parent and model as arguments.
class TreeModelCompleter : public QCompleter
{
Q_OBJECT
Q_PROPERTY(QString separator READ separator WRITE setSeparator)
public:
explicit TreeModelCompleter(QObject *parent = 0);
explicit TreeModelCompleter(QAbstractItemModel *model, QObject *parent = 0);
QString separator() const;
public slots:
void setSeparator(const QString &separator);
protected:
QStringList splitPath(const QString &path) const override;
QString pathFromIndex(const QModelIndex &index) const override;
private:
QString sep;
};The class reimplements the protected functions https://() and https://() to suit a tree model. For more information on customizing https:// to suit tree models, refer to https://.
TreeModelCompleter also has a separator property which is declared using the https://() macro. The separator has READ and WRITE attributes and the corresponding functions separator() and setSeparator(). For more information on https://(), refer to https://.
TreeModelCompleter Class Implementation▲
The first constructor constructs a TreeModelCompleter object with a parent while the second constructor constructs an object with a parent and a https://, model.
TreeModelCompleter::TreeModelCompleter(QObject *parent)
: QCompleter(parent)
{
}
TreeModelCompleter::TreeModelCompleter(QAbstractItemModel *model, QObject *parent)
: QCompleter(model, parent)
{
}The separator() function is a getter function that returns the separator string.
QString TreeModelCompleter::separator() const
{
return sep;
}As mentioned earlier, the splitPath() function is reimplemented because the default implementation is more suited to https:// or list models. In order for https:// to split the path into a list of strings that are matched at each level, we split it using https://() with sep as its separator.
QStringList TreeModelCompleter::splitPath(const QString &path) const
{
if (sep.isNull()) {
return QCompleter::splitPath(path);
}
return path.split(sep);
}The pathFromIndex() function returns data for the completionRole() for a tree model. This function is reimplemented as its default implementation is more suitable for list models. If there is no separator, we use https://'s default implementation, otherwise we use the https://() function to navigate upwards and accumulate the data. The function then returns a https://, dataList, using a separator to join objects of different levels.
QString TreeModelCompleter::pathFromIndex(const QModelIndex &index) const
{
if (sep.isNull()) {
return QCompleter::pathFromIndex(index);
}
// navigate up and accumulate data
QStringList dataList;
for (QModelIndex i = index; i.isValid(); i = i.parent()) {
dataList.prepend(model()->data(i, completionRole()).toString());
}
return dataList.join(sep);
}MainWindow Class Definition▲
The MainWindow class is a subclass of https:// and implements five custom slots: about(), changeCase(), changeMode(), highlight(), and updateContentsLabel().
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = 0);
private slots:
void about();
void changeCase(int);
void changeMode(int);
void highlight(const QModelIndex&);
void updateContentsLabel(const QString&);In addition, the class has two private functions, createMenu() and modelFromFile(), as well as private instances of https://, https://, https://, TreeModelCompleter and https://.
private:
void createMenu();
QAbstractItemModel *modelFromFile(const QString& fileName);
QTreeView *treeView;
QComboBox *caseCombo;
QComboBox *modeCombo;
QLabel *contentsLabel;
TreeModelCompleter *completer;
QLineEdit *lineEdit;
};MainWindow Class Implementation▲
The MainWindow's constructor creates a MainWindow object with a parent and initializes the completer and lineEdit. The createMenu() function is invoked to set up the "File" menu and "Help" menu. The completer's model is set to the https:// obtained from modelFromFile(), and the https://() signal is connected to MainWindow's highlight() slot.
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent), completer(0), lineEdit(0)
{
createMenu();
completer = new TreeModelCompleter(this);
completer->setModel(modelFromFile(":/resources/treemodel.txt"));
completer->setSeparator(QLatin1String("."));
QObject::connect(completer, SIGNAL(highlighted(QModelIndex)),
this, SLOT(highlight(QModelIndex)));
QWidget *centralWidget = new QWidget;
QLabel *modelLabel = new QLabel;
modelLabel->setText(tr("Tree Model<br>(Double click items to edit)"));
QLabel *modeLabel = new QLabel;
modeLabel->setText(tr("Completion Mode"));
modeCombo = new QComboBox;
modeCombo->addItem(tr("Inline"));
modeCombo->addItem(tr("Filtered Popup"));
modeCombo->addItem(tr("Unfiltered Popup"));
modeCombo->setCurrentIndex(1);
QLabel *caseLabel = new QLabel;
caseLabel->setText(tr("Case Sensitivity"));
caseCombo = new QComboBox;
caseCombo->addItem(tr("Case Insensitive"));
caseCombo->addItem(tr("Case Sensitive"));
caseCombo->setCurrentIndex(0);The https:// objects modelLabel, modeLabel and caseLabel are instantiated. Also, the https:// objects, modeCombo and caseCombo, are instantiated and populated. By default, the completer's mode is "Filtered Popup" and the case is insensitive.
QLabel *separatorLabel = new QLabel;
separatorLabel->setText(tr("Tree Separator"));
QLineEdit *separatorLineEdit = new QLineEdit;
separatorLineEdit->setText(completer->separator());
connect(separatorLineEdit, SIGNAL(textChanged(QString)),
completer, SLOT(setSeparator(QString)));
QCheckBox *wrapCheckBox = new QCheckBox;
wrapCheckBox->setText(tr("Wrap around completions"));
wrapCheckBox->setChecked(completer->wrapAround());
connect(wrapCheckBox, SIGNAL(clicked(bool)), completer, SLOT(setWrapAround(bool)));
contentsLabel = new QLabel;
contentsLabel->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
connect(separatorLineEdit, SIGNAL(textChanged(QString)),
this, SLOT(updateContentsLabel(QString)));
treeView = new QTreeView;
treeView->setModel(completer->model());
treeView->header()->hide();
treeView->expandAll();
connect(modeCombo, SIGNAL(activated(int)), this, SLOT(changeMode(int)));
connect(caseCombo, SIGNAL(activated(int)), this, SLOT(changeCase(int)));
lineEdit = new QLineEdit;
lineEdit->setCompleter(completer);We use a https:// to place all the objects in the MainWindow.
QGridLayout *layout = new QGridLayout;
layout->addWidget(modelLabel, 0, 0); layout->addWidget(treeView, 0, 1);
layout->addWidget(modeLabel, 1, 0); layout->addWidget(modeCombo, 1, 1);
layout->addWidget(caseLabel, 2, 0); layout->addWidget(caseCombo, 2, 1);
layout->addWidget(separatorLabel, 3, 0); layout->addWidget(separatorLineEdit, 3, 1);
layout->addWidget(wrapCheckBox, 4, 0);
layout->addWidget(contentsLabel, 5, 0, 1, 2);
layout->addWidget(lineEdit, 6, 0, 1, 2);
centralWidget->setLayout(layout);
setCentralWidget(centralWidget);
changeCase(caseCombo->currentIndex());
changeMode(modeCombo->currentIndex());
setWindowTitle(tr("Tree Model Completer"));
lineEdit->setFocus();
}The createMenu() function sets up the https:// objects required and adds them to the "File" menu and "Help" menu. The https://() signals from these actions are connected to their respective slots.
void MainWindow::createMenu()
{
QAction *exitAction = new QAction(tr("Exit"), this);
QAction *aboutAct = new QAction(tr("About"), this);
QAction *aboutQtAct = new QAction(tr("About Qt"), this);
connect(exitAction, SIGNAL(triggered()), qApp, SLOT(quit()));
connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));
connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));
QMenu* fileMenu = menuBar()->addMenu(tr("File"));
fileMenu->addAction(exitAction);
QMenu* helpMenu = menuBar()->addMenu(tr("About"));
helpMenu->addAction(aboutAct);
helpMenu->addAction(aboutQtAct);
}The changeMode() function accepts an index corresponding to the user's choice of completion mode and changes the completer's mode accordingly.
void MainWindow::changeMode(int index)
{
QCompleter::CompletionMode mode;
if (index == 0)
mode = QCompleter::InlineCompletion;
else if (index == 1)
mode = QCompleter::PopupCompletion;
else
mode = QCompleter::UnfilteredPopupCompletion;
completer->setCompletionMode(mode);
}The about() function provides a brief description on the Tree Model Completer example.
void MainWindow::about()
{
QMessageBox::about(this, tr("About"), tr("This example demonstrates how "
"to use a QCompleter with a custom tree model."));
}The changeCase() function alternates between https:// and https:// modes, depending on the value of cs.
void MainWindow::changeCase(int cs)
{
completer->setCaseSensitivity(cs ? Qt::CaseSensitive : Qt::CaseInsensitive);
}main() Function▲
The main() function instantiates MainWindow and invokes the https://() function to display it.
int main(int argc, char *argv[])
{
Q_INIT_RESOURCE(treemodelcompleter);
QApplication app(argc, argv);
MainWindow window;
window.show();
return app.exec();
}List of Files▲
Files:
List of Files▲
-
tools/treemodelcompleter/main.cpp
-
tools/treemodelcompleter/mainwindow.cpp
-
tools/treemodelcompleter/mainwindow.h
-
tools/treemodelcompleter/treemodelcompleter.cpp
-
tools/treemodelcompleter/treemodelcompleter.h
-
tools/treemodelcompleter/treemodelcompleter.pro
-
tools/treemodelcompleter/treemodelcompleter.qrc