How to set QListWidget in particular position - c++

How do i set QListWidget in particular position say i have window size of(1000,1000) and i want to set QListWidget at position (200,200).
widget = new QWidget();
setCentralWidget(widget);
list1->setFixedSize(200,150);
list1->addItem("Surya TV");
list1->addItem("Sony TV");
list1->addItem("Zee TV");
vertical->addWidget(list1);
widget->setLayout(vertical);

You can use :
void move ( int x, int y )
Something like :
p = new QListWidget(this);
p->move(200,200);
In my case "this" is the QMainWindow.
Does it helps?

Please use spacers with predefined sizes to pad your list if you are going for layouts. It is better to go for layouts if you have more widgets along with the listWidget in your main form.
If you are unsure, please use Designer to build your forms. This will allow you to have the kind of control you wish achieve in terms of fine grained positioning.
Personally, I do not prefer designer though.

Related

Qt Desktop on Mac: QFormLayout sizing with subpanels

TL;DR: I'm having a grow/shrink probably using embedded forms inside a MainWindow. I'm unsure what to try next.
Okay, I have another sizing problem.
This is a sample app of what I'm trying to do:
When I click on the various toolbar options, I intend to change the central widget contents accordingly. Maybe I should just use a tab widget, but I wanted to do it this way.
In the simplest form, with a widget layout like this:
I set the central widget's layout to Horizontal, and the Inner Widget to FormLayout then set the inner widget's expand rules to expand any expandable fields. As I resize the window, the simple line edit expands and contracts as desired.
When I click the bus icon in the toolbar, I swap out the contents of the central widget with a separate panel. That panel has a widget with a form layout, and is also set to expand and collapse. Here are the layout rules for the second panel:
My trigger code does this:
currentCenter = ui->innerWidget; // In the constructor
currentCenter->hide();
if (v1Form == nullptr) {
v1Form = new V1Form(ui->centralWidget);
}
v1Form->show();
currentCenter = v1Form;
I have tried various orders to this, and I tried using setCentralWidget(). In all cases, the new central area remains a fixed size, even though the original one expands and collapses.
What is working: I can readily change the inner contains for different forms. That's working great. (It took a while to figure it out.)
-or- I can make simple popup forms that grow and shrink properly.
What is not working is grow/shrink when I embed my form inside my central widget or if I use setCentralWidget.
I'm not sure what else to try.
Maybe I should just use a tab widget, but I wanted to do it this way.
You should definitely use a QTabWidget as your central widget. It is designed specifically for your use case, and it will greatly simplify your code.
My trigger code does this:
currentCenter = ui->innerWidget; // In the constructor
currentCenter->hide();
if (v1Form == nullptr) {
v1Form = new V1Form(ui->centralWidget);
}
v1Form->show();
currentCenter = v1Form;
With a QTabWidget, your trigger code can be simplified to:
ui->innerTabWidget->setIndex(1).
You don't need to dynamically construct a V1Form. Simply use Qt Designer to create multiple pages in your QTabWidget and implement all your subpanel widgets within your MainWindow.ui.
(Nonetheless, if you want to implement each subpanel in its own separate *.ui file, you can still promote each page in your QTabWidget to your custom widget.)
What is not working is grow/shrink when I embed my form inside my central widget or if I use setCentralWidget.
To address your original symptoms: Your widgets don't grow/shrink because you didn't put them inside a layout that is part of your main window.
I found a solution doing it the way I started. I had to add one line of code:
void MainWindow::switchForm(QWidget *widget) {
if (centralForm != widget) {
if (centralForm != nullptr) {
centralForm->hide();
centralForm = nullptr;
}
if (widget != nullptr) {
centralForm = widget;
centralForm->show();
ui->centralwidget->layout()->addWidget(centralForm);
}
}
}
void MainWindow::on_actionSetup_triggered()
{
if (setupForm == nullptr) {
setupForm = new SetupForm(ui->centralwidget);
}
switchForm(setupForm);
}
The missing line -- adding my new form to the layout:
ui->centralwidget->layout()->addWidget(centralForm);

Replace a widget in Qt

I have a base class which has some gui items that i have set positions of using the designer in Qt creator. Those items are:
QWidget* w1;
QWidget* w2;
QWidget* w3;
Now in a class that inherits that base class, I would like to "transform" those widgets into lineEdit items, that would keep all the geometrical parameters of that widgets. So I do something like this:
QLineEdit* leAmplitude;
leAmplitude = new QLineEdit(ui->w1);
leAmplitude->setGeometry(ui->w1->geometry());
ui->glControls->addWidget(leAmplitude);
But the added QLineEdit item doesn't appear in the exact same place as w1 item. Its just added at the bottom of other controls in the QGridLayout glControls. How to make the lineEdit to take all geometric parameters from w1?
Layout takes care of the widgets placed in the layout, according to the hints given by the widget, so calling setGeometry, then doing addLayout is not useful. Also, adding widget to layout resets it parent, so you setting new widget's parent to ui->w1 is not useful either.
Fortunately, there is QLayout::replaceWidget method! Just use that. Example:
QLineEdit* leAmplitude;
leAmplitude = new QLineEdit;
QLayoutItem *previous = ui->glControls->replaceWidget(ui->w1, leAmplitude);
// possibly assert that previous is ui->w1, or just delete it, or whatever
This method was added as late as in Qt 5.2 it seems, so if you need to support older versions, I can expand this answer to cover how to (try to) do the same manually. But in short, you have to use the right QGridLayout::addWidget overload and make sure relevant properties (including at least sizeHint and sizePolicy) match.
try this, it is works:
QLineEdit* leAmplitude;
leAmplitude = new QLineEdit(ui->w1->parentWidget());
ui->w1->parentWidget()->layout()->replaceWidget(ui->w1, leAmplitude);
ui->w1 = leAmplitude;

How to logically group widgets in QT for easy show/hide?

I'm grouping a set of widgets in a parent and then I control the visibility/flow of these widgets by hiding/showing the parent. Is this a good way to achieve what I'm trying to do? Here is the code:
QVBoxLayout* l = new QVBoxLayout(this);
// .....
QWidget* toolset_frame = new QWidget(this);
{
QVBoxLayout* l = new QVBoxLayout(toolset_frame);
l->addWidget(new QLabel(tr("Stuff")));
this->Toolset = new QLineEdit(toolset_frame);
l->addWidget(this->Toolset);
}
l->addWidget(toolset_frame);
// Call toolset_frame->hide() and this hides everything inside the parent
The problem with this solution is that the children shrink in size slightly, I think this is due to some padding or border in the parent. Ideally the children should appear as if they are not contained in an intermediate object, but rather flow with the parent. In this case the horizontal size of the children should not be affected.
http://doc.qt.io/qt-5/qtwidgets-dialogs-extension-example.html
This example shows that your approach is correct. Using a widget to contain the elements you want to hide, and so on.
If you want the margins/content margins/padding to be less, then change it.
// in finddialog.cpp
extensionLayout->setMargin(0);
To quickly prototype what properties to change to get it to look right, try laying it out in the Qt Designer, and modify the property editor to get the look and feel you want.
Hope that helps.

Qt get active text box

If I have two text boxes in my main window how can I check which one is active/being used by the user?
You can use QApplication::focusWidget() function to see which widget currently has focus.
Or you can use the QWidget::hasFocus() function to see if your text box has focus.
edit_A = new QTextEdit(this);
edit_B = new QTextEdit(this);
.
.
.
void MyClass::someFunction()
{
if(edit_A->hasFocus())
//edit_A is being used
else if(edit_B->hasFocus())
//edit_B is being used
}
The previous answer is right but just in case you want to monitor more components you can use
QWidget * QApplication::focusWidget ()
to get widget with focus.
This approach will allow you to make cleaner code if you wanted to have more widgets monitored. Instead of having a ladder of ifs just use some kind of look-up table to choose what action to take.

QDockWidget Draggable Tabs

I am using QDockWidgets and placing two of them on the left side of my application so that tabs can be used to select between them. However, Qt's default behavior for this looks horrible and is unintuitive. Instead of being able to drag the tabs to move the widgets, it places another bar below the selected tab (with the same name) that must be dragged instead. As a user, it would be hard to figure this out.
(My QDockWidgets are "Attributes" and "Library")
Is there a way to get rid of this second bar and make it so I can move my QDockWidgets by dragging the tabs themselves?
If you are adding QTabWidgets to a main window derived from QMainWindow, you can try tabifyDockWidget.
It tabifies two QDockWidgets just like you wanted and of course you are able to drag them.
dockWidget1 = new QDockWidget("Tab1") ;
dockWidget2 = new QDockWidget("Tab2") ;
this->addDockWidget(Qt::LeftDockWidgetArea , dockWidget1 );
this->addDockWidget(Qt::LeftDockWidgetArea , dockWidget2 );
this->tabifyDockWidget(dockWidget1,dockWidget2);
I think, Tom was not too far away from a solution:
You can set your own Widget as title bar:
myDockingWidget->setTitleBarWidget(myTitleBar)
If you design this widget to not show the dock window title, you have it. Via the signal QDockWidget::topLevelChanged your docking widget can even become informed, when it gets floating, so you could then enable the title in myTitleBar again.
As far as I can see from QDockWidget::mousePressEvent implementation in src/gui/widgets/qdockwidget.cpp dragging the dockwidgets using tabs is NOT possible:
QDockWidgetLayout *dwLayout
= qobject_cast<QDockWidgetLayout*>(layout);
if (!dwLayout->nativeWindowDeco()) {
QRect titleArea = dwLayout->titleArea();
if (event->button() != Qt::LeftButton ||
!titleArea.contains(event->pos()) ||
// check if the tool window is movable... do nothing if it
// is not (but allow moving if the window is floating)
(!hasFeature(this, QDockWidget::DockWidgetMovable) && !q->isFloating()) ||
qobject_cast<QMainWindow*>(parent) == 0 ||
isAnimating() || state != 0) {
return false;
}
initDrag(event->pos(), false);
....
As you can see from the implementation one of the things that the QDockWidget checks before allowing undocking is whether the mouse press event has come from title bar or not.
have you tried:
myDockingWidget->setTitleBarWidget(0)
edit:
QWidget* titleWidget = new QWidget(this);
mUi.dockWidget->setTitleBarWidget(titleWidget);
where 'this' is a QMainWindow
this will remove the title bar, though im not sure how to make the QDockWidget draggable from the tabs
Edited:
Please do not use this method. It introduces problems rather than soloves them.
Maybe you can try this wierd way, that is move the QWidget in the dock widget area to the title bar.
I modify the demo in folder
C:\Qt\Qt5.12.9\Examples\Qt-5.12.9\widgets\mainwindows\dockwidgets
to show how it works:
In "void MainWindow::createDockWindows()"
QDockWidget *dock = new QDockWidget(tr("Customers"), this);
dock->setAllowedAreas(Qt::LeftDockWidgetArea | Qt::RightDockWidgetArea);
//make a panel to hold your widgets
QWidget *p = new QWidget(dock);
QVBoxLayout *l = new QVBoxLayout(p);
p->setLayout(l);
customerList = new QListWidget(p);
l->addWidget(customerList);
customerList->addItems(QStringList()
<< "John Doe, Harmony Enterprises, 12 Lakeside, Ambleton"
<< "Jane Doe, Memorabilia, 23 Watersedge, Beaton"
<< "Tammy Shea, Tiblanka, 38 Sea Views, Carlton"
<< "Tim Sheen, Caraba Gifts, 48 Ocean Way, Deal"
<< "Sol Harvey, Chicos Coffee, 53 New Springs, Eccleston"
<< "Sally Hobart, Tiroli Tea, 67 Long River, Fedula");
dock->setWidget(new QWidget());//hide the real dock area
dock->setTitleBarWidget(p); //use the titlebar erea to show the content
The demo:
Drag the edge of the panel to move, actually you can drag the empty area (no child widget area). The widget on this panel still functional properly.
I also think that setTitleBarWidget() really does the trick. I remember seeing it being used for a similar purpose in the source code of the Amarok music player. Amarok has a QMainWindow which only contains dock widgets. You might want to have a look at the source code there.
It looks like you've set your dock tab position to be on the top. The default is for it to be on the bottom. Then it's not as visually jarring to have the tab text right next to the title bar text.
I don't think there's any way to do what you're proposing in Qt (eliminate the QDockWidget title bar and drag from the tab), at least not with the standard widgets. You could probably write a lot of custom code to make it happen, but that's probably not worth it.
Instead, I'd suggest moving the tabs to the bottom (see QMainWindow::setTabPosition) or possibly one of the sides.