I want to enhance my code which works but I fail to do so and my problem is how to pass arguments properly, I mean:
void pracownik2::on_pushButton_4_clicked(){
this->setWindowTitle("EKRAN");
QWidget *centralWidget = new QWidget;
int licznik=1;
QString licz;
//QString kolumny = ui->lineEdit->text();
//QString wiersze = ui->lineEdit_2->text();
miejsca2 = ui->lineEdit_3->text().toInt();
//QPushButton *button[wiersze.toInt()][kolumny.toInt()];
QPushButton *button[3][6];
QGridLayout *controlsLayout = new QGridLayout;
for(int i=0;i<3;i++)
{
for(int j=0;j<6;j++)
{
licz = QString::number(licznik);
licznik++;
button[i][j] = new QPushButton(licz);
button[i][j]->setCheckable(1);
if(tab[i][j]==1)
button[i][j]->setEnabled(false);
controlsLayout->addWidget(button[i][j], i, j);
}
}
QPushButton *okej = new QPushButton("Zatwierdź");
QPushButton *anul = new QPushButton("Anuluj");
controlsLayout->addWidget(okej, 3, 0);
controlsLayout->addWidget(anul, 3, 1);
controlsLayout->setHorizontalSpacing(0);
controlsLayout->setVerticalSpacing(0);
centralWidget->setLayout(controlsLayout);
setCentralWidget(centralWidget);
for(int i=0;i<3;i++)
{
for(int j=0;j<6;j++)
{
connect(button[i][j],SIGNAL(toggled(bool)),this,SLOT(tescik(bool)));
}
}
connect(anul,SIGNAL(clicked()),this,SLOT(close()));
connect(okej,SIGNAL(clicked()),this,SLOT(okay2()));}
void pracownik2::tescik(bool t){
if (t)
{
miejsca++;
}
else
{
miejsca--;
}}
This is working so far and I want 'tescik' function also to set values of my array:
void pracownik2::tescik(bool t, int i, int j){
if (t)
{tab[i][j]=1;
miejsca++;
}
else
{tab[i][j]=0;
miejsca--;
}}
I can't pass 'i' and 'j' indexes of current qpushbutton and I have no idea how to edit my connect line
connect(button[i][j],SIGNAL(toggled(bool)),this,SLOT(tescik(bool,int,int)));
it still has no idea what do I mean by int,int and I still have no idea how to make it work :)
Your problem is because of arguments mismatch when trying to connect signal and slot (signal is emitted with only one boolvalue, when slot takes three) - you should recieve corresponding message in your's application output. One of the solutions is to use QObject-dynamic properties. You can do something like this when creating your buttons:
button[i][j] = new QPushButton(licz);
button[i][j]->setProperty("i", i);
button[i][j]->setProperty("j", j);
And after that you can rewrite your slot:
void pracownik2::tescik(bool t) {
int i = QObject::sender()->property("i").toInt();
int j = QObject::sender()->property("j").toInt();
if (t)
{tab[i][j]=1;
miejsca++;
}
else
{tab[i][j]=0;
miejsca--;
}}
Related
I want to get QString text from selected QComboBox. When I selected an index on a QComboBox, I want to get QString from the selected index, after I clicked the desired index on a QcomboBox.
I have researched about this,
Qt QCombobox currentIndexChanged signal
but have not found a way to solve it,
QVector<QComboBox*> cboxes;
for (int i =0; i< 40 ; i++)
{
QComboBox *box = new QComboBox();
cboxes.append(box);
}
for(int i = 0; i < 40; i++)
{
connect(cboxes[i], SIGNAL(currentIndexChanged(const QString &text)), this, SLOT(comboBoxAdjusted_Changed(QString)));
}
comboBoxAdjusted_Changed function
void DialogSettings::comboBoxAdjusted_Changed(QString text)
{
std::cout << text.toStdString() << endl;
}
I have Try, but everytime i change the combobox index, It isn't give output.
for (int i =0; i< 40 ; i++)
{
connect(cboxes[i], static_cast<void(QComboBox::*)(const QString &)>(&QComboBox::currentIndexChanged),
[=](const QString &text){
std::cout << text.toStdString() << endl;
});
What should I do?
I see signal syntax is missing the function input argument.
Below are two valid signals for currentIndexChanged
void currentIndexChanged(int index)
void currentIndexChanged(const QString &text)
If you have to handle index try below for your case.
for(int i = 0; i < 40; i++)
{
connect(cboxes[i], static_cast<void(QComboBox::*)(int)>(&QComboBox::currentIndexChanged),[=](int index){ /* YOUR CODE */ });
}
I get the following error:
QWidget: must construct a QApplication before a widget
It worked 3 days ago, but now it doesn't work anymore, and I don't know why.
What does this error mean? I don't know if I modified something.
Here is my code:
mainwindw.cpp
void MainWindow::on_Statistic_button_clicked(){
s1 =new stat1(this);
s1->show();
}
stat1.cpp
stat1::stat1(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::stat1)
{
ui->setupUi(this);
//mLayout = new QVBoxLayout;
mChart = new OpenChart(this);
setCentralWidget(mChart);
//mLayout->addWidget(mChart);
//mLayout->setMargin(0);
//setLayout(mLayout);
//int num;
QSqlQuery q,q1,q2;
q1.exec("SELECT count(distinct adresse) from abonne");
q1.next();
int n = q1.value(0).toInt();
QString adr[100];
int j = 0;
q.exec("SELECT distinct adresse from abonne");
while(j<n)
{
q.next();
adr[j]=q.value(0).toString();
j++;
}
QMap<QString,int> cartes;
for(j=0;j<n;j++)
{
q2.exec("SELECT count(abonne.id_abonne) FROM abonne,fidels where abonne.id_abonne=fidels.id_abonne and abonne.adresse='"+adr[j]+"'");
q2.next();
int nbr = q2.value(0).toInt();
cartes[adr[j]] = nbr;
}
mChart->setTitle("Cartes/Adresses");
mChart->setTipo(OpenChart::Sectores_2D);
mChart->setTipoleyenda(OpenChart::Circular);
const auto cartesEnd=cartes.end();
for(auto i=cartes.begin(); i!=cartesEnd; ++i){
mChart->addItem(i.key(), i.value());
}
}
stat1::~stat1()
{
delete ui;
}
I want to get QString text from selected QComboBox. When I selected an index on a QComboBox, I want to get QString from the selected index, after I clicked the desired index on a QcomboBox.
I have researched about this,
Qt QCombobox currentIndexChanged signal
but have not found a way to solve it,
QVector<QComboBox*> cboxes;
for (int i =0; i< 40 ; i++)
{
QComboBox *box = new QComboBox();
cboxes.append(box);
}
for(int i = 0; i < 40; i++)
{
connect(cboxes[i], SIGNAL(currentIndexChanged(const QString &text)), this, SLOT(comboBoxAdjusted_Changed(QString)));
}
comboBoxAdjusted_Changed function
void DialogSettings::comboBoxAdjusted_Changed(QString text)
{
std::cout << text.toStdString() << endl;
}
I have Try, but everytime i change the combobox index, It isn't give output.
for (int i =0; i< 40 ; i++)
{
connect(cboxes[i], static_cast<void(QComboBox::*)(const QString &)>(&QComboBox::currentIndexChanged),
[=](const QString &text){
std::cout << text.toStdString() << endl;
});
What should I do?
I see signal syntax is missing the function input argument.
Below are two valid signals for currentIndexChanged
void currentIndexChanged(int index)
void currentIndexChanged(const QString &text)
If you have to handle index try below for your case.
for(int i = 0; i < 40; i++)
{
connect(cboxes[i], static_cast<void(QComboBox::*)(int)>(&QComboBox::currentIndexChanged),[=](int index){ /* YOUR CODE */ });
}
I am working in Qt 4.7, and I have a QWidget object in my dialog. I need to go through each of the children and extract the current text into a QStringList. Every other object is a QCheckBox, and the rest are QComboBoxes (I would just need the text portion of both). So far the only way I could think of to do this would be to use the children() function to get them as QObject*'s and cast them, like this:
QStringList textlist;
for(int i = 0; i < ui->myWidget->children().size(); i++)
{
if(i % 2 == 0)
{
QCheckBox *q = (QCheckBox *)ui->myWidget->children().at(i);
textlist.append(q->text());
}
else
{
QComboBox *q = (QComboBox *)ui->myWidget->children().at(i);
textlist.append(q->currentText());
}
}
However, when I try to use this, it builds and compiles fine, but then crashes when it's run. I checked and both classes are subclasses (albeit indirectly through QAbstractButton and QWidget) of QObject, which is the type of the objects in the list ui->myWidget->children(), so I feel like they should be able to cast this way. I haven't worked much with this kind of thing before so I'm not sure if there's a better way to do this. If anyone has any ideas, it would be greatly appreciated. Thanks!
UPDATE: So, I can't get the casting to work this way or with the qobject_cast. I HAVE however discovered that I can go from QObject to QWidget, and I think I should be able to go from QWidget to the needed objects with dynamic_cast, but that doesn't work either. Right now I have this:
QStringList textlist;
for(int i = 0; i < ui->myWidget->children().size(); i++)
{
QWidget *qw = qobject_cast<QWidget*>(ui->myWidget->children().at(i)
if(i % 2 == 0)
{
QComboBox *q = dynamic_cast<QComboBox*>(qw);
if(q)
{
textlist.append(q->text());
}
}
else
{
QCheckBox *q = dynamic_cast<QCheckBox*>(qw);
if(q)
{
textlist.append(q->currentText());
}
}
}
If anyone has any ideas, I'd appreciate the help. Thank you.
UPDATE2: I haven't found much online that helps with this still, so I may as well ask as well, if there is anyway to do this WITHOUT casting, i.e. getting the objects directly from the QWidget in their original type, I would really appreciate that as well. I'm not heartset on my current strategy or anything, it was just the only way I could think to do it - I'll take anything that works at this point.
You should think about using qobject_cast. After the cast you should also check if the object is valid.
QStringList textlist;
for(int i = 0; i < ui->myWidget->children().size(); i++)
{
if(i % 2 == 0)
{
QCheckBox *q = qobject_cast<QCheckBox*>(ui->myWidget->children().at(i));
if(q)
textlist.append(q->text());
}
else
{
QComboBox *q = qobject_cast<QComboBox*>(ui->myWidget->children().at(i));
if(q)
textlist.append(q->currentText());
}
}
But this still seems like a bad design to me. The widget class that contains the comboboxes and checkboxes should have a function, that goes through the checkboxes and comboboxes and returns a QStringList. Then you could just call that function.
Here is an example
mywidget.h:
namespace Ui {
class MyWidget;
}
class MyWidget : public QWidget
{
Q_OBJECT
public:
explicit MyWidget(QWidget *parent = 0);
~MyWidget();
QStringList getComboTextList();
QStringList getCheckBoxTextList();
private:
Ui::MyWidget *ui;
QList<QComboBox*> comboList;
QList<QCheckBox*> checkList;
};
mywidget.cpp:
MyWidget::MyWidget(QWidget *parent) :
QWidget(parent),
ui(new Ui::MyWidget)
{
ui->setupUi(this);
this->setLayout(new QVBoxLayout);
for(int i = 0; i < 5; i++)
{
QCheckBox *checkBox = new QCheckBox(this);
this->layout()->addWidget(checkBox);
checkBox->setText(QString("Check box #%1").arg(i));
checkList.append(checkBox);
}
for(int i = 0; i < 5; i++)
{
QComboBox *comboBox = new QComboBox(this);
this->layout()->addWidget(comboBox);
comboBox->addItem("Combo box item 1");
comboBox->addItem("Combo box item 2");
comboList.append(comboBox);
}
}
MyWidget::~MyWidget()
{
delete ui;
}
QStringList MyWidget::getComboTextList()
{
QStringList returnList;
for(int i = 0; i < comboList.length(); i++)
{
returnList << comboList[i]->currentText();
}
return returnList;
}
QStringList MyWidget::getCheckBoxTextList()
{
QStringList returnList;
for(int i = 0; i < checkList.length(); i++)
{
returnList << checkList[i]->text();
}
return returnList;
}
Then in your other class you can just call getCheckBoxTextList or getComboTextList like this:
QStringList comboTextList = myWidget->getComboBoxList();
QStringList checkTextList = myWidget->getCheckBoxTextList();
I am working in Qt 4.7, and I have a QWidget object in my dialog. I need to go through each of the children and extract the current text into a QStringList. Every other object is a QCheckBox, and the rest are QComboBoxes (I would just need the text portion of both). So far the only way I could think of to do this would be to use the children() function to get them as QObject*'s and cast them, like this:
QStringList textlist;
for(int i = 0; i < ui->myWidget->children().size(); i++)
{
if(i % 2 == 0)
{
QCheckBox *q = (QCheckBox *)ui->myWidget->children().at(i);
textlist.append(q->text());
}
else
{
QComboBox *q = (QComboBox *)ui->myWidget->children().at(i);
textlist.append(q->currentText());
}
}
However, when I try to use this, it builds and compiles fine, but then crashes when it's run. I checked and both classes are subclasses (albeit indirectly through QAbstractButton and QWidget) of QObject, which is the type of the objects in the list ui->myWidget->children(), so I feel like they should be able to cast this way. I haven't worked much with this kind of thing before so I'm not sure if there's a better way to do this. If anyone has any ideas, it would be greatly appreciated. Thanks!
UPDATE: So, I can't get the casting to work this way or with the qobject_cast. I HAVE however discovered that I can go from QObject to QWidget, and I think I should be able to go from QWidget to the needed objects with dynamic_cast, but that doesn't work either. Right now I have this:
QStringList textlist;
for(int i = 0; i < ui->myWidget->children().size(); i++)
{
QWidget *qw = qobject_cast<QWidget*>(ui->myWidget->children().at(i)
if(i % 2 == 0)
{
QComboBox *q = dynamic_cast<QComboBox*>(qw);
if(q)
{
textlist.append(q->text());
}
}
else
{
QCheckBox *q = dynamic_cast<QCheckBox*>(qw);
if(q)
{
textlist.append(q->currentText());
}
}
}
If anyone has any ideas, I'd appreciate the help. Thank you.
UPDATE2: I haven't found much online that helps with this still, so I may as well ask as well, if there is anyway to do this WITHOUT casting, i.e. getting the objects directly from the QWidget in their original type, I would really appreciate that as well. I'm not heartset on my current strategy or anything, it was just the only way I could think to do it - I'll take anything that works at this point.
You should think about using qobject_cast. After the cast you should also check if the object is valid.
QStringList textlist;
for(int i = 0; i < ui->myWidget->children().size(); i++)
{
if(i % 2 == 0)
{
QCheckBox *q = qobject_cast<QCheckBox*>(ui->myWidget->children().at(i));
if(q)
textlist.append(q->text());
}
else
{
QComboBox *q = qobject_cast<QComboBox*>(ui->myWidget->children().at(i));
if(q)
textlist.append(q->currentText());
}
}
But this still seems like a bad design to me. The widget class that contains the comboboxes and checkboxes should have a function, that goes through the checkboxes and comboboxes and returns a QStringList. Then you could just call that function.
Here is an example
mywidget.h:
namespace Ui {
class MyWidget;
}
class MyWidget : public QWidget
{
Q_OBJECT
public:
explicit MyWidget(QWidget *parent = 0);
~MyWidget();
QStringList getComboTextList();
QStringList getCheckBoxTextList();
private:
Ui::MyWidget *ui;
QList<QComboBox*> comboList;
QList<QCheckBox*> checkList;
};
mywidget.cpp:
MyWidget::MyWidget(QWidget *parent) :
QWidget(parent),
ui(new Ui::MyWidget)
{
ui->setupUi(this);
this->setLayout(new QVBoxLayout);
for(int i = 0; i < 5; i++)
{
QCheckBox *checkBox = new QCheckBox(this);
this->layout()->addWidget(checkBox);
checkBox->setText(QString("Check box #%1").arg(i));
checkList.append(checkBox);
}
for(int i = 0; i < 5; i++)
{
QComboBox *comboBox = new QComboBox(this);
this->layout()->addWidget(comboBox);
comboBox->addItem("Combo box item 1");
comboBox->addItem("Combo box item 2");
comboList.append(comboBox);
}
}
MyWidget::~MyWidget()
{
delete ui;
}
QStringList MyWidget::getComboTextList()
{
QStringList returnList;
for(int i = 0; i < comboList.length(); i++)
{
returnList << comboList[i]->currentText();
}
return returnList;
}
QStringList MyWidget::getCheckBoxTextList()
{
QStringList returnList;
for(int i = 0; i < checkList.length(); i++)
{
returnList << checkList[i]->text();
}
return returnList;
}
Then in your other class you can just call getCheckBoxTextList or getComboTextList like this:
QStringList comboTextList = myWidget->getComboBoxList();
QStringList checkTextList = myWidget->getCheckBoxTextList();