Qt Creator Align button float to the top - c++

I have this gridlayout added onto my centralWidget of my UI in Qt Creator. And I wanted to add several buttons onto the gridlayout. My code is as follows:
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
QPushButton *button1 = new QPushButton();
button1->setText("hello");
ui->gridLayout->addWidget(button1, 0,0);
}
MainWindow::~MainWindow()
{
delete ui;
}
Even though the button is added, it is seen appearing in the middle of the UI when the program is run. And there is a huge gap between the menu bar and button. How do i go about adding the button so that the button will flow nicely below the menu bar?
Please advice.
Thanks

The grid layout was placed in the middle of the UI in design mode, so anything you place inside will fill the fixed rectangle of the grid layout.
To make the grid layout fill the main window, right click the main window and click Lay out > Lay out vertically.
You can also fix the huge gap by placing a vertical spacer below the grid layout.

I guess this method work as well. By setting the alignment for the addWidget portion.
eg: ui->gridLayout->addWidget(button1, 0,0, Qt::AlignTop);

Related

Change QMainWindow layout programmatically in c++

I am using Creator to build main MainWindow and I populate it with all my widgets.
I do not set any MainWindow lay out in this stage (like "Lay out in a Grid" or "Lay out Horizontally".
When I launch the Application I want to dynamically change the MainWindow layout of widgets in it to "Lay out in a Grid" like in Creator mode by pressing the left button.
I’ve tried hard all possible combinations reading many posts around.
this solution:
Qt: Can't set layout in QMainWindow
doesn't work and it does not make much sense to me.
I've tried:
QGridLayout * MainWindowLayout = new QGridLayout;
ui->setupUi(this);
centralWidget()->setLayout(MainWindowLayout);
NO LUCK
I've tried to put all my widgets inside a big widget at desegn time named MainWindowWidget and then setting it as a centralWidget
QGridLayout * MainWindowLayout = new QGridLayout;
ui->setupUi(this);
setCentralWidget(ui->MainWindowWidget);
centralWidget()->setLayout(MainWindowLayout);
NO LUCK
Ain't there any way to change the MainWindow widget's layout like "Lay ouy in a Grid" at design time when using the Creator??
EDIT:
To be more specific with NO LUCK I mean that the widgets are not placed as in a grid as expected.
Here is a code snipped that you can try on an empty application
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
, ui(new Ui::MainWindow)
{
/*
Place some widgets at design time with Creator (at least 2) in the MainWindow form
in a misplaced order and do not apply any "Lay out xxx" right button on QT Creator
*/
ui->setupUi(this);
/* HERE I WANT THE MainWindow or either an Object to take a specific Layout */
QGridLayout * MainWindowLayout = new QGridLayout;
ui->setupUi(this);
centralWidget()->setLayout(MainWindowLayout);
}
It is almost 2 days that I am googling and I can't find any way out
Thank you all for your help...
You are creating the layout But you are not adding widgets to it. This should fix your issue:
ui->setupUi(this);
QGridLayout *MainWindowLayout = new QGridLayout();
MainWindowLayout->addWidget(ui->label, 0, 0);
MainWindowLayout->addWidget(ui->label_2, 0, 1);
// Add all other widgets to your layout...
centralWidget()->setLayout(MainWindowLayout);
#C137
Finally I got it working doing the following:
I places all my form widgets into 3 different widgets (containers QFrame in my case).
Then I placed them into the Layout as suggested and it worked.
This solution is a bit tricky
QGridLayout *MainWindowLayout = new QGridLayout();
MainWindowLayout->addWidget(ui->MainFrame, 0, 0); // MainFrame --> My new object containing other widgets
MainWindowLayout->addWidget(ui->DebugButtonsFrame, 0, 1); // DebugButtonsFrame as above
MainWindowLayout->addWidget(ui->DebugMemoFrame, 1, 0); // DebugMemoFrame as above
// Add all other widgets to your layout...
centralWidget()->setLayout(MainWindowLayout);
QT is handling this task in its own way a bit confusing from my point of view. While I was using Embarcadero the Layout were much much easier to manage.
I thought there could me a method to easily set the MainWindow Layout as in Creator mode which was much much easier and faster to handle.
So far it worked as expected but still confusing.
Thank you all for the support.

Two QWidget in QMainWindow to have minimize button and window title

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
textEdit1 = new QTextEdit();
textEdit1->setWindowTitle("First Notepad");
textEdit2 = new QTextEdit();
textEdit2->setWindowTitle("First Notepad");
layout = new QVBoxLayout();
layout->addWidget(textEdit1);
layout->addWidget(textEdit2);
newTab = new QWidget();
newTab->setLayout(layout);
ui->setupUi(this);
setCentralWidget(newTab);
}
The above is my code sample of the MainWindow constructor. Ot has two qTextEdits which are in a VerticalBox layout. I want both the textEdits to have a title bar and minimize and maximize button so that at a time I can use one of them or both of them. But as you can see the output the Window Title bars are not there.
How can I make the Title bar appear? Why is it that setWindowTitle("First Notepad") do not display the Title?
If I am doing it wrong please suggest as what other way I can proceed. Any suggestion is welcome.
What I am trying is like one MainWindow having multiple sub-windows with fixed positions.
What I am trying is like one MainWindow having multiple sub-windows with fixed positions.
What you are looking for is probably a QMdiArea along with multiple QMdiSubWindow.
As mentioned in the documentation of `QMdiArea:
The QMdiArea widget provides an area in which MDI windows are displayed
Moreover:
QMdiArea is commonly used as the center widget in a QMainWindow to create MDI applications, but can also be placed in any layout.
I've used it, but I've never tried to give fixed positions to the subwindows. Anyway it's apparently possible. Probably QMdiArea::tileSubWindows is already enough for your requirements.
Set custom titles and bars to the windows is given for free instead:
QMdiSubWindow represents a top-level window in a QMdiArea, and consists of a title bar with window decorations, an internal widget, and (depending on the current style) a window frame and a size grip. QMdiSubWindow has its own layout, which consists of the title bar and a center area for the internal widget
See the official documentation for further details.

QTextEdit::setPalette is not updating the text color

I am changing the text color of two QTextEdit widgets along with quite a few other QLineEdits. This happens whenever I disable or enable the readonly property to make it better visually.
QPalette* disablePallete;
QPalette* enabledPallete;
disablePallete->setColor(QPalette::Text,Qt::darkGray);
enabledPallete->setColor(QPalette::Text,Qt::black);
// disable writing
ui->TextEdit->setPalette(*disablePallete);
// enable writing
ui->TextEdit->setPalette(*enablePallete);
This works perfectly on all of my LineEdits the instant I change the palette.
My problem is that the text inside the QTextEdits does not update immediately, and only does so when I click something inside the box, or edit the text. It glitches too and only updates where the cursor is moved to.
here is an example.
I got around it by doing this each time. It forces a repaint on everything.
ui->roomDescriptionTextEdit->append("");
ui->roomDescriptionTextEdit->undo();
Even though this works, I would like a less hacky way to update all of the text color on a QTextEdit.
Does anyone know of a solution?
I have only QTextEdit and QPushbutton on the form and it is working fine for me. If you won't find the error then please provide you full code.
#include "mainwindow.h"
#include "ui_mainwindow.h"
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
connect(ui->pushButton, SIGNAL(clicked(bool)), this, SLOT(_handleClicked(bool)));
}
void MainWindow::_handleClicked(bool ok)
{
QPalette palette;
palette.setColor(QPalette::Text,Qt::darkGray);
ui->textEdit->setPalette(palette);
}
MainWindow::~MainWindow()
{
delete ui;
}
QTextEdit can handle rich text and QTextDocument controls that. Now properties of QTextEdit can control text which doesn't have rich text property set. If some part of text has some property set (color, bold, font, ...) this overrides default values from QTextEdit.
So most probably you have pasted rich text into text edit or performed some edit which set rich text values.

Placing buttons at the center in horizontal line in QT

I am new QT and trying to develop the desktop application.
Currently I am facing a issue of alignment. I am using QTCreator 3.1.2 based on qt 5.3.1
I have 3 buttons placed in the windows as
After running application, If I resize the windows then buttons didn't stay in the center. like image 1 and if size is less then it is like image 2
I have tried using the hbox, but it didn't solve the problem and also scroll bar is also not visible in the window.
Would you please tell me how can I make these buttons to stay in the center only?
Thanks a lot
You can create QHBoxLayout passing this as its parent, which will set that layout as the layout of that widget, then add QPushButtons to that layout:
Widget::Widget(QWidget *parent) : QWidget(parent) {
// Prepare the horizonal layout, adding buttons
horizontalLayout = new QHBoxLayout(this);
pushButton = new QPushButton(this);
horizontalLayout->addWidget(pushButton);
pushButton_2 = new QPushButton(this);
horizontalLayout->addWidget(pushButton_2);
pushButton_3 = new QPushButton(this);
horizontalLayout->addWidget(pushButton_3);
// Set the layout of the central widget
setLayout(horizontalLayout);
}

How can I restore the initial centralwidget of the QMainWindow?

I am kinda of new to Qt and decided to play around with it a bit so that one day I may be able to make some programs with a GUI. I've been playing around with windows and encountered a problem. I created two new QWidget Form classes in addition to the QMainWindow. With one of them, I was able to make a separate window popup and disappear. What I am trying to do with the second one is this...
I have a MainWindow with a button, and when that button is pressed, the CentralWidget changes to the QWidget with another button. Then, when I press a button on the new button, it restores the CentralWidget to the original one.
I did try storing the initial CentralWidget before changing it but I have yet to be able to successfully restore it. I do know about QStackedWidget, but I would like to know if there is another way of doing it. THANK YOU!
It seems Qt deletes child widget, when new one assigned as child widget. The fallowing code illustrates it and shows workaround
class QMyWidget: public QWidget
{
public:
~QMyWidget(){std::cout<<"Destroyed"<<std::endl;}
};
class QMyWidget2: public QWidget
{
public:
~QMyWidget2(){std::cout<<"Destroyed2"<<std::endl;}
};
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
this->setCentralWidget(new QMyWidget());
this->setCentralWidget(new QWidget);
QWidget * w = new QMyWidget2();
this->setCentralWidget(w);
w->setParent(NULL);
this->setCentralWidget(new QWidget);
}
MainWindow::~MainWindow()
{
delete ui;
}
Do you want QStackedWidget? It's a but like QTabWidget but without the, er, tabs.