QDialog expanding base on the QLabel content - c++

I'd like to show and then close a dialog after 5 seconds. The dialog needs to be automatically resized (horizontally and vertically) based on the content of a label. Here is my code:
#include <QApplication>
#include <QDialog>
#include <QLabel>
#include <QTimer>
void notify (int intTime=1000)
{
QDialog notify;
notify.setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
notify.setWindowFlag(Qt::FramelessWindowHint);
QLabel *lbl = new QLabel(&notify);
lbl->setText("This is a test This is a test This is a test This is a test This is a test This is a test This is a test");
QApplication::processEvents();
notify.adjustSize();
QTimer::singleShot(intTime, &notify, SLOT(close()));
notify.exec();
}
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
notify(5000);
exit(0);
// return a.exec();
}
It does not not expand the dialog based on the label size. Here is how it looks:
How can I fix it? (Please also let me know if there is better way of doing this.)
I am using Qt5 in Linux.

Since you have not used a QLayout the QLabel will be displayed as large as you can, a possible request is to change the size of QDialog to the recommended size of QLabel with sizeHint():
#include <QApplication>
#include <QDialog>
#include <QLabel>
#include <QTimer>
void notify (int intTime=1000)
{
QDialog notify;
notify.setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
notify.setWindowFlag(Qt::FramelessWindowHint);
QLabel *lbl = new QLabel(&notify);
lbl->setText("This is a test This is a test This is a test This is a test This is a test This is a test This is a test");
QApplication::processEvents();
notify.resize(lbl->sizeHint());
QTimer::singleShot(intTime, &notify, SLOT(close()));
notify.exec();
}
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
notify(5000);
exit(0);
// return a.exec();
}
The other possible solution is to use a QLayout:
#include <QApplication>
#include <QDialog>
#include <QLabel>
#include <QTimer>
#include <QVBoxLayout>
void notify (int intTime=1000)
{
QDialog notify;
QVBoxLayout *lay = new QVBoxLayout(&notify);
//notify.setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
notify.setWindowFlag(Qt::FramelessWindowHint);
QLabel *lbl = new QLabel;
lay->addWidget(lbl);
lbl->setText("This is a test This is a test This is a test This is a test This is a test This is a test This is a test");
QApplication::processEvents();
QTimer::singleShot(intTime, &notify, SLOT(close()));
notify.exec();
}
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
notify(5000);
exit(0);
// return a.exec();
}

Related

I don't understand why it won't connect

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QWidget w;
QPushButton *trankil = new QPushButton("Clique&&Release", &w);
QVBoxLayout *layoutrkl = new QVBoxLayout;
layoutrkl->addWidget(trankil);
//trankil->move(10,10);
int resultat = 2;
QLCDNumber *lcd = new QLCDNumber(&w);
QLabel *lelabel = new QLabel("bonsoir");
QPushButton *trankil2 = new QPushButton("Clique&&Release2", &w);
layoutrkl->addWidget(trankil2);
layoutrkl->addWidget(lelabel);
layoutrkl->addWidget(lcd);
QObject::connect(trankil, SIGNAL(clicked()),lcd, SLOT(display(resultat)));
w.setLayout(layoutrkl);
w.show();
return a.exec();
}
The connect doesn't work and i don't understand why at all !
There is no problem about how it appear, but if i click the QPushbutton, the QLCD won't display resultat
Thanks for your help
PS : There is my includes :
#include <QApplication>
#include <QVBoxLayout>
#include <QLCDNumber>
#include <QPushButton>
#include <QLabel>
#include <QObject>
If you debug it.
QObject::connect: No such slot QLCDNumber::display(resultat)
display(resultat) is not a slot function.
You can try the following:
QObject::connect(trankil, &QPushButton::clicked, lcd, [&](){
lcd->display(QString::number(resultat));
});

How do I make a QTreeView fill the whole dialog and resize with it?

I have a QTreeView and I can't find a way of making it fill the whole dialog window and resize with the window when it is resized.
Something like this:
#include <QApplication>
#include <QDialog>
#include <QHBoxLayout>
#include <QTreeView>
class MyDialog: public QDialog
{
public:
MyDialog()
{
QHBoxLayout* l = new QHBoxLayout(this);
setLayout(l);
QTreeView* v = new QTreeView(this);
l->addWidget(v);
}
};
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MyDialog d;
d.exec();
return a.exec();
}

layout does not work in Visual Studio 2015?

I want to use layout in qt5, but In Visual Studio 2015 the layout does not work?
Here is my code:
layout.h code
#ifndef LAYOUT_H
#define LAYOUT_H
#include <QtWidgets/QMainWindow>
#include "ui_layout.h"
class layout : public QMainWindow
{
Q_OBJECT
public:
layout(QWidget *parent = 0);
~layout();
private:
Ui::layoutClass ui;
};
#endif // LAYOUT_H
main.cpp
#include "layout.h"
#include <QtWidgets/QApplication>
#include <QtWidgets/QPushButton>
#include <QtWidgets/QHBoxLayout>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
layout w;
QHBoxLayout hb;
QPushButton b("button 0");
QPushButton b1("button 1");
hb.addWidget(&b);
hb.addWidget(&b1);
w.setLayout(&hb);
w.show();
return a.exec();
}
Here is my result:
How to fix this problem?
QMainWindow is a special widget since it has default widgets like QStatusbar, QMenuBar, etc. When working with this widget we must place the new elements in the centralWidget.
So we must assign a widget that will be our centralWidget, and then to this we add the layouts as shown below:
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
layout w;
w.setCentralWidget(new QWidget);
QHBoxLayout hb;
QPushButton b("button 0");
QPushButton b1("button 1");
hb.addWidget(&b);
hb.addWidget(&b1);
w.centralWidget()->setLayout(&hb);
w.show();
return a.exec();
}

How to hide application on taskbar?

I am trying to hide my QT application from taskbar? I cannot find anything in Google so I asking here.
Solution from Qt Hide Taskbar Item (Qt Hide Taskbar Item) and this->hide() is not helping.
main.cpp
#include "status_bar.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
status_bar w;
w.show();
return a.exec();
}
status_bar.cpp:
#include "status_bar.h"
#include "ui_status_bar.h"
#include <stdlib.h>
#include <QTime>
#include <QTimer>
#include <QApplication>
#include <QDesktopWidget>
status_bar::status_bar(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::status_bar)
{
ui->setupUi(this);
setWindowFlags(Qt::Window | Qt::FramelessWindowHint | Qt::WindowStaysOnTopHint);
resize(QApplication::desktop()->width(),36);
ui->time->move(QApplication::desktop()->width()-ui->time->size().width(),10);
ui->username->setText(getenv("USER"));
timeupdate = new QTimer(this);
connect(timeupdate, SIGNAL(timeout()),
this, SLOT(UpdateClock()));
timeupdate->start(100);
}
void status_bar::UpdateClock()
{
ui->time->setText(QTime::currentTime().toString("HH:mm"));
}
status_bar::~status_bar()
{
delete ui;
}
EDIT:
With code like this window is empty.
class MyWindowWidget : public QWidget
{
public:
MyWindowWidget(QWidget *parent)
: QWidget(parent, Qt::Dialog)
{
}
};
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
status_bar window;
MyWindowWidget widget(&window);
widget.show();
return app.exec();
}
Solved by using Qt::Tool flag.
Qt::Tool flag has other problems for me, like this widget/windows is hidden when its state becomes inactive.
I would recommend you to use Qt::ToolTip

in Qt Gui how to make a button randomly appear every click

Alright so is there any way to make this program randomly change the variables x and y every time the button is clicked i am new to programming...
#include <QtGui/QApplication>
#include "mainwindow.h"
#include <QtGUI>
#include <QWidget>
#include <cstdlib>
#include <ctime>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QWidget *window = new QWidget;
srand(time(0));
int x = 1+(rand()%900);
int y = 1+(rand()%400);
QPushButton *MainInter = new QPushButton("Push me!",window);
QPropertyAnimation *animation = new QPropertyAnimation(MainInter, "pos");
animation->setDuration(0);
animation->setEndValue(QPoint(x,y));
Object::connect(MainInter,SIGNAL(released()),animation,SLOT(start()));
window->resize(900,500);
window->show();
return a.exec();
}
What you can do is, instead of connecting the released() signal of your button directly to your animations start() SLOT, you would create your own custom SLOT. Then you connect the button to it, handle the action, and call the animation.
First read up on how to create a custom QWidget, instead of creating top level object in your main(). Simple example here
A custom widget might look like this:
widget.h
#ifndef WIDGET_H
#define WIDGET_H
#include <QWidget>
class QPushButton;
class QPropertyAnimation;
class MyWidget : public QWidget
{
Q_OBJECT
public:
MyWidget(QWidget *parent = 0);
private:
QPushButton *button;
QPropertyAnimation *animation;
public slots:
void randomizeAnim();
};
#endif // WIDGET_H
widget.cpp
#include "widget.h"
#include <QPushButton>
#include <QPropertyAnimation>
#include <ctime>
MyWidget::MyWidget(QWidget *parent) :
QWidget(parent)
{
button = new QPushButton("Push me!", this);
animation = new QPropertyAnimation(button, "pos");
animation->setDuration(0);
QObject::connect(button, SIGNAL(released()), this, SLOT(randomizeAnim()));
}
void MyWidget::randomizeAnim()
{
srand(time(0));
int x = 1+(rand()%900);
int y = 1+(rand()%400);
animation->setEndValue(QPoint(x,y));
animation->start();
}
And now your main.cpp can be reduced to the boilerplate code:
#include <QApplication>
#include "widget.h"
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QWidget *window = new MyWidget;
window->resize(900,500);
window->show();
return a.exec();
}
Every time you click, your custom slot will handle the action and do the animation.