Set text for statusbar in QtDesigner? - c++

By default, if I create a new Form in QtDesigner, of type "Main Window", I get three elements in there: centralwidget, menubar - which is not visible in Preview (Ctrl-R), unless actual menu entries are added; and statusbar.
The problem is - by default, the statusbar is the same background color as the rest, and so, when I do a Preview, I cannot really perceive whether the statusbar is there or not:
Basically, the only thing I can see is the "sizeGrip", which is not always easy to see - so I would like to have a text/message shown in the statusbar as well.
Now, I know that the API for QStatusBar Class has .showMessage used to show text in a statusbar - however, I cannot find any similar field in QtDesigner?!
So - is it possible to set a default/placeholder text in the statusbar in QtDesigner - and if so, how?

No, you cannot.
In QtDesigner, you can only set properties of a widget (see Q_PROPERTY), not invoke methods. The properties are listed in the Properties section of the documentation, and QStatusBar only has sizeGripEnabled (and the inherited properties from QWidget)
But what is the actual problem? You cannot clearly make out the status bar in the preview? The preview is supposed to help in checking singal/slots and layout constraints, not as a full functioning application.
There are also things that will influence the actual look&feel in the final application that cannot be checked in designer preview, like dynamic stylesheets, or custom styles.
if you want to check how your window looks like with text in the statusbar, you will need to make a mock-application that does just this: show some text
#include <QtCore>
#include <QtWidgets>
#include "ui_mainwindow.h"
int main(int argc, char **argv) {
QApplication app(argc, argv);
Ui::MainWindow ui;
QMainWindow wnd;
ui.setupUi(&wnd);
wnd.show();
ui.statusbar->showMessage("Hello World!");
return app.exec();
}

Related

How to add "status bar" to QT widget - without using QTDesigner

I am creating QT QEditText widget (C++) dynamically at run time.
I cannot use "static ways" AKA QTDesigner to add / design the widget - it is NOT a form.
I know "status bar" is used as default in "MainWindow".
I want to add same functions in QTextEdit.
The QT doc has an example of C++ code on how to use "status bar" in MainWindow - that is of little help.
I have added this code to the QTextEdit constructor
childStatusBar = new QStatusBar();
childStatusBar->setStatusTip(" Show current copy drag and drop text");
childStatusBar->showNormal();
childStatusBar->showMessage("Status test message");
It compiles and runs, but there is no "status bar".
I do not know what is missing in my code and would
appreciate an assistance in solving this issue.
(Links , references to code examples would be helpful)
Please make sure to
read the post
and replay with facts, not opinions.
Suggestion for alternates are NOT solutions.
Please avoid any format of "ask your friend", RTFM.
Been there, done that.
As far as Mt Higgins is concerned, I am not asking for editing my post - I am not
posting to get a lecture in English grammar or composition.
Cheers and
"... thanks for watching..."
Just create a Qt MainWindow or Widget example and create a statusbar on it. Build the project and you can find your ui_...h in your build directory. Open it and find the QStatusBar widget. You can copy from there.
Note: Layouts are very important in Qt. So don't forget main-widget / main-window main layout and it's relation with statusbar. And also statusbar's layout.
As we can see in QStatusBar document :
Typically, a request for the status bar functionality occurs in
relation to a QMainWindow object. QMainWindow provides a main
application window, with a menu bar, toolbars, dock widgets and a
status bar around a large central widget
So you need something like this code:
#include <QApplication>
#include <QMainWindow>
#include <QStatusBar>
#include <QTextEdit>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QMainWindow *w = new QMainWindow();
w->resize(600, 400);
QTextEdit *textEdit = new QTextEdit(w);
textEdit->setStatusTip("Show current copy drag and drop text");
auto childStatusBar = new QStatusBar(w);
childStatusBar->showMessage("Status test message");
w->setStatusBar(childStatusBar);
w->setCentralWidget(textEdit);
w->show();
return a.exec();
}
and also QTextEdit has a setStatusTip function that you can add "Show current copy drag and drop text" there instead of childStatusBar.
NOTED: As I mentioned ‍QTextEdit‍ cannot have ‍QStatusBar as you use in your code.
Now, if you don't want to use this method(use QMainWindow ), you have to create a custom and personalized class for yourself.
This means that you have to write the StatusBar by yourself

Qt generate UI based on template

I'm looking to generate a set of labels and buttons based on some kind of template, but I don't know how to do the template part.
I'll be using a tab widget which I already have set up, and in one the tabs, I want to have a two labels, a custom button, and a textbox. It'll be repeated around 40-50 times (dependent on a given value at startup) and have spacing as needed.
Once I have a template, I foresee calling it in a loop and setting the appropriate displayed text(Label_1, Label_2, etc) and connect statements where needed.
As I said, I don't know how to template parts of the UI so they can be placed in a kind of auto-generation.
I had thought of making one group, copying the xml, and somehow adding it but that doesn't seem to be a proper way. A little new to Qt.
This is roughly the layout I want to repeat. It has two labels, a lineedit, and one pushbutton.
There's no "good" way to do this in QtDesigner/QtCreator. At best you could copy/paste the set of controls 50 times and then in C++ code hide the ones you don't need. But I wouldn't recommend this.
Instead, just create the controls (labels/button/text box), and a layout to hold them, in C++ code, inside a loop which iterates however many times you need at runtime. Insert the controls layout into the tab widget page layout which you have set up in designer mode. It is not difficult, and will actually be more efficient than what QtDesigner produces since that tends to generate more code than you typically need in the first place.
As a starting point, you could look at the C++ code which is generated by the Qt UI Compiler (UIC) tool for your current design (it takes the XML from designer and turns it into C++ code). You can find this in the build folder for your project, typically named something like ui_ClassName.h, probably in a ui subfolder of the build tree.
UPDATE:
Another, possibly better, way to do this is to create the "template" QWidget class/form, which is going to be used multiple times, as a separate object. The "template" design could be created/maintained using QtCreator/Designer (or just directly in C++). The (possible) advantage here is that as the app requirements evolve, the template widget can be expanded with additional functionality or even re-used in other parts of the UI.
For example, I'd assume the text editor and button in the given mockup image will actually need to do something (eg. edit data and submit it). So some basic functionality can be built into the "template" widget, for example to emit a signal with the text contents of the line editor when the button is pressed.
I put together a quick example. I'm creating the simple MainWindow in pure C++ to simplify/shorten the example code. The "template" I'm calling an Editor. The Editor class and UI form I initially created with the QtCreator wizard (New -> Qt Designer Form Class). I then added the label/control widgets in designer mode. And in C++, a textEdited(const QString &text) signal in the header, and in the Editor() constructor a lambda connection to emit that signal when the button is pressed.
The Editor class code is straight out of the QtCreator wizard except for two edits I'm highlighting below. The designer form has two relevant controls: a QLineEdit (lineEdit) and a QPushButton (pushButton). I'll link to the full files below.
Editor.h
// in the Editor class declarations:
signals:
void textEdited(const QString &text) const;
Editor.cpp
// in the constructor, after ui->setupUi(this);
connect(ui->pushButton, &QPushButton::clicked, this, [this]() {
emit textEdited(ui->lineEdit->text());
});
Test harness, including MainWindow subclass and main()
#include <QApplication>
#include <QMainWindow>
#include <QTabWidget>
#include <QBoxLayout>
#include <QMessageBox>
#include "Editor.h"
class MainWindow : public QMainWindow {
Q_OBJECT
public:
MainWindow() : QMainWindow()
{
// set up a tab widget as the window central widget
QTabWidget *tabWidget = new QTabWidget(this);
setCentralWidget(tabWidget);
// the first/only page will contain all the editors in a vertical layout
QWidget *editorsPage = new QWidget(this);
editorsPage->setLayout(new QVBoxLayout());
// add the editors container page to tab widget
tabWidget->addTab(editorsPage, tr("Editors page"));
// Now create a number of editor widgets using our Editor class "template"
int layoutItems = 5; // number of editors needed, could be dynamic
for (int i=0; i < layoutItems; ++i) {
// Create an Editor instance with the tab page as parent
Editor *editor = new Editor(editorsPage);
// Add the editor widget to the tab page layout
editorsPage->layout()->addWidget(editor);
// A simple connection with the editor signal, as way of example.
connect(editor, &Editor::textEdited, this, [this](const QString &text) {
// just show a message box with the editor text
QMessageBox::information(this, tr("Text Edited"), text, QMessageBox::Ok);
});
}
}
};
int main(int argc, char **argv)
{
QApplication app(argc, argv);
MainWindow mainWindow;
mainWindow.show();
return app.exec();
}
#include "main.moc"
Links The full Editor code:
Editor.h
Editor.cpp
Editor.ui
The XML in Qt Creator is for UIC in QMake to generator code for you.
For example, QMake translates your mainwindow.ui to ui_mainwindow.h, and within you will find void setupUi(QMainWindow *MainWindow) with the actual code that creates and places the widgets.
Look at this code, the docs, and create and place the widgets yourself by code.
For example, adding 5 checkboxes to a groupbox by code:
QVBoxLayout *l = new QVBoxLayout(this);
ui->groupBox_4->setLayout(l);
for(int i=0; i<5; i++){
QCheckBox *c = new QCheckBox(this);
l->addWidget(c);
}

How to set an icon to a new button in QDialogButtonBox?

I'm trying to make a custom button with an icon in QDialogButtonBox in a Qt5 program (Qt 5.5.1) on Kubuntu 14.04. Reading this answer, I understand that it's not recommended to simply edit the stock buttons, so I use QDialogButtonBox::addButton with my custom button. But for some reason, although I do succeed in changing icon of the stock button, my custom button still remains without any icon after using QPushButton::setIcon.
Here's the code
#include <QApplication>
#include <QDialogButtonBox>
#include <QPushButton>
int main(int argc, char** argv)
{
QApplication app(argc,argv);
QDialogButtonBox bbox(QDialogButtonBox::Close);
const auto button=new QPushButton(QObject::tr("Convert..."));
bbox.addButton(QObject::tr("Convert..."), QDialogButtonBox::ApplyRole);
const auto icon=QIcon::fromTheme("system-run");
// This doesn't work - the button remains without icon
button->setIcon(icon);
// But this does
bbox.button(QDialogButtonBox::Close)->setIcon(icon);
bbox.show();
return app.exec();
}
What am I doing wrong? How can I have an icon on my custom button without the need to edit stock buttons?
You are creating two buttons. One button which you don't show anywhere, and one that you add in bbox. And you are setting the icon for the button that you don't show anywhere.
Fix your code so you don't create two separate buttons, and set an icon for the button you are putting in bbox:
QPushButton *button = bbox.addButton(QObject::tr("Convert..."), QDialogButtonBox::ApplyRole);
...
button->setIcon(icon);

implementing custom completer, popup window steal the focus

I need to implement custom completer, similar to QCompleter but containing customized widgets. I got stuck at the very beginning, I can't make the popup work as it should work. In the following example I attach a completer (well, just a plain widget) to the first line edit. The second line edit is there just to test the focus in/out behavior. The problem is that when the popup displays, it steals the focus from the line edit. But this is not what I want, I want to be able to keep typing in the line edit. I tried several other options as commented out in the code below, but non of them worked.
#include <QApplication>
#include <QLineEdit>
#include <QHBoxLayout>
#include <QWidget>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QWidget container;
QLineEdit editor;
QLineEdit editor2;
QHBoxLayout layout(&container);
layout.addWidget(&editor);
layout.addWidget(&editor2);
QWidget completer; // or QWidget completer(&editor);?
//completer.setFocusProxy(&editor); // tried this, but it does not help
completer.setWindowFlags(Qt::Popup);
// the following lines are an alternative to Qt::Popup but the window
// does not close automatically, which is a problem
// e.g. when moving or resizing the parent window
//completer.setAttribute(Qt::WA_ShowWithoutActivating);
//completer.setWindowFlags(Qt::Tool | Qt::FramelessWindowHint);
QObject::connect(&editor, &QLineEdit::textEdited,
[&] {
completer.resize(editor.width(), 100);
completer.move(editor.mapToGlobal(QPoint(0, editor.height())));
completer.show();
// editor.setFocus(); // does not help either
});
container.show();
return a.exec();
}
How to implement custom completer?
UPDATE: From the docs, I read that "A popup widget is a special top-level widget that sets the Qt::WType_Popup widget flag, e.g. the QMenu widget. When the application opens a popup widget, all events are sent to the popup. Normal widgets and modal widgets cannot be accessed before the popup widget is closed."
So it seems that when I open a popup it automatically receives the events and therefore I have to forward the events to the line edit using QCoreApplication::sendEvent(editor, event); inside my Completer::keyPressEvent. This seems to work fine except the fact that the cursor in the line edit is not visible or not blinking.
Just apply this method to your completer widget:
setWindowFlags(Qt::Tool | Qt::FramelessWindowHint|Qt::WindowStaysOnTopHint);
It works for me.

How to put osgEarth's ViewerWidget into an tabbed MdiArea?

Is there something special about putting osgEarth's ViewerViewer into a QMdiArea? I created a QMdiArea as central Widget (called setCentralWidget) instead of taking osgEarth's viewer directly as central widget.
QMdiArea *mdiArea = new QMdiArea(this);
setCentralWidget(mdiArea); // call to QMainWindows method, snippet is taken from app's MainWindow
mdiArea->addSubWindow(viewerWidget); // this doesn't work, globe is not drawn
Everything I tried didn't worked... except osgEarth's ViewerWidget is set as central widget of my MainWindow. Also tried MultiViewerWidget without any success but because I need only one view the ViewerWidget should be ok, or not?
I had a look into the examples but didn't succed to use one of them as starting point.
Any hints? Thank's in advance.
you can try this, where Form1 is a QDialog
in main.cpp
int main()
{
QApplication a(argc, argv);
Form1 w=new Form1();//qdialog
.................//do something to initial the map
w.loadWidget(viewerWidget);
w.show();//the order of the loadwiget() and show() is important!!!!!
a.exec();
}
in Form1.cpp
void Form1::loadWidget(QWidget *qwidget)
{
qwidget->setMinimumSize( ui.mdiArea->width(),ui.mdiArea->height());
QMdiSubWindow * subW=ui.mdiArea->addSubWindow(qwidget);
subW->setWindowFlags(Qt::SubWindow | Qt::FramelessWindowHint);
subW->maximumSize();
}
This works well with qt 4.8.4+osgearth 2.3
Try setting the subwindow's geometry before starting the UI.
QMdiSubWindow* sw = mdiArea->addSubWindow(viewerWidget);
sw->setGeometry(...);
Otherwise OSG will probably become confused.
Got this answer by Gwaldron in the osgEarth forum here and it worked.
Also setting a minimum size for the viewerWidget will help (e.g. for positioning on TabWidget). See my question and answer here.