I have created a QList of QPushButton that I have assigned to a slot function.
But I would like to get coordinates of the button which is clicked in the list.
For example, pushbutton n°5 is clicked, it return me (25,150).
listButton = new QList<QPushButton*>;
//some code here
QPushButton *button = new QPushButton(QString::number(1),ui->widget);
button->setGeometry(50, 50, 30, 30);
button->setStyleSheet("background-color:red;");
QObject::connect(button, SIGNAL(clicked()), this, SLOT(selectP()));
listeButton->append(button);
//some code here
void selectP()
{
//I'd like to print here, coordinates of the button which has called "selectP()"
}
Sorry for my language, thanks in advance !
In you slot you can get the pointer of the button that had been clicked:
void selectP()
{
QPushButton *btn = qobject_cast<QPushButton *>(sender());
if (btn) {
qDebug() << "The coordinates are:" << btn->geometry();
}
}
Related
I would like to delete row where QPushButton is clicked how it is possible to I think it is reasonable to use slots but how to do it don't know , if you have any ideas how to get a row of selected button please share, thanks.
It is my table
It is a code where i add rows to my QTableWidget
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
for(int i = 0; i<20;i++)
ui->tableWidget->insertRow(ui->tableWidget->rowCount());
QVector<QString>vec;
vec<<"first"<<"sec"<<"third"<<"for"<<"fif"<<"first"<<"sec"
<<"third"<<"for"<<"fif";
vec<<"first"<<"sec"<<"third"<<"for"<<"fif"<<"first"<<"sec"
<<"third"<<"for"<<"fif";
for(int i = 0; i<ui->tableWidget->rowCount();i++)
{
for(int j = 0; j<ui->tableWidget->columnCount();j++)
{
if(j == 0)
{
QWidget* pWidget = new QWidget();
QPushButton* btn_edit = new QPushButton();
btn_edit->setText("Remove");
QHBoxLayout* pLayout = new QHBoxLayout(pWidget);
pLayout->addWidget(btn_edit);
pLayout->setAlignment(Qt::AlignCenter);
pLayout->setContentsMargins(0, 0, 0, 0);
pWidget->setLayout(pLayout);
ui->tableWidget->setCellWidget(i, j, pWidget);
continue;
}
QTableWidgetItem*item = new QTableWidgetItem(vec[i]);
item->setFlags(item->flags() ^ Qt::ItemIsEditable);
ui->tableWidget->setItem(i, j, item);
}
}
}
This task can be solved using the removeRow() method but before we must get the row. First of all we will connect all the buttons to a slot inside the loop as shown below:
*.h
private slots:
void onClicked();
*.cpp
[...]
QPushButton* btn_edit = new QPushButton();
btn_edit->setText("Remove");
connect(btn_edit, &QPushButton::clicked, this, &MainWindow::onClicked);
[...]
In the slot we can get the button that emits the signal through the sender() method, then we get QWidget parent (created with the name pWidget), this is the widget that is added to the QTableWidget and its position is relative to it, then we use the method indexAt() to get the QModelIndex associated with the cell, and this has the information of the row through the method row(). All of the above is implemented in the following lines:
void MainWindow::onClicked()
{
QWidget *w = qobject_cast<QWidget *>(sender()->parent());
if(w){
int row = ui->tableWidget->indexAt(w->pos()).row();
ui->tableWidget->removeRow(row);
ui->tableWidget->setCurrentCell(0, 0);
}
}
Note: The setCurrentCell() method is used to set the focus since the last cell that has it has been deleted.
The complete example can be found in the following link.
When you are creating QPushButton just add :
btn_delete = new QPushButton("Remove", ui->tableWidget);
btn_delete->setObjectName(QString("%1").arg(ui->tableWidget->rowCount()));
connect(btn_delete, SIGNAL(clicked()), this, SLOT(CellButtonDeleteClicked()));
And create function CellButtonDeleteClicked()
void CellButtonDeleteClicked()
{
// by this line I can get the sender of signal
QPushButton *pb = qobject_cast<QPushButton *>(QObject::sender());
int row = pb->objectName().toInt();
ui->tableWidget->removeRow(row);
}
In a QWidget like QLabel, how can we set a "?" button, such that when clicked (or hovered) it should show some help text.
Also you can use QMenu instead of QPushButton + QLabel.
// Constructor
setContextMenuPolicy(Qt::CustomContextMenu);
connect(this, SIGNAL(customContextMenuRequested(QPoint)), this, SLOT(slotCustomMenu(QPoint)));
// slotCustomMenu(QPoint)
QMenu menu(this);
menu.addAction(this->toolTip());
menu.addAction(this->whatsThis());
menu.exec(QCursor::pos());
Easiest way to show help when hover QWidget: setToolTip(QString) and setToolTipDuration(int).
If you want a "?" button, just implement your own QWidget. Then via ui designer or directly in your code add QPushButton and QLabel on layout, and show your QLabel with help text in position of cursor when clicked(). Something like this:
{
// Constructor
...
m_mainLabel = new QLabel("Main text");
m_button = new QPushButton("?");
m_helpLabel = new QLabel("Help text");
connect(m_button, SIGNAL(clicked(bool)),
this, SLOT(slotShowOrHideHelpLabel(bool)));
QHBoxLayout *hBoxLayout = new QHBoxLayout;
hBoxLayout->addWidget(m_mainLabel);
hBoxLayout->addWidget(m_button);
setLayout(hBoxLayout);
}
void slotShowOrHideHelpLabel(bool showHelpLabel)
{
if (showHelpLabel)
{
m_helpLabel->show();
m_helpLabel->move(QCursor::pos());
}
else
{
m_helpLabel->hide();
}
}
In one of my windows I made a button responsible for creating dynamic array of buttons. After they are made I can't make 'anul' button close the window
Here's the code
QWidget *centralWidget = new QWidget;
int licznik=1;
QString licz;
QString kolumny = ui->lineEdit->text();
QString wiersze = ui->lineEdit_2->text();
QPushButton *button[wiersze.toInt()][kolumny.toInt()];
QGridLayout *controlsLayout = new QGridLayout;
for(int i=0;i<wiersze.toInt();i++)
{
for(int j=0;j<kolumny.toInt();j++)
{
licz = QString::number(licznik);
licznik++;
button[i][j] = new QPushButton(licz);
button[i][j]->setCheckable(1);
controlsLayout->addWidget(button[i][j], i, j);
}
}
QPushButton *okej = new QPushButton("Zatwierdź");
QPushButton *anul = new QPushButton("Anuluj");
if(anul->isDown() == true)
this->close();
controlsLayout->addWidget(okej, wiersze.toInt(), 0);
controlsLayout->addWidget(anul, wiersze.toInt(), 1);
controlsLayout->setHorizontalSpacing(0);
controlsLayout->setVerticalSpacing(0);
centralWidget->setLayout(controlsLayout);
setCentralWidget(centralWidget);
I also tried to change this->close() with centralWidget->close()
This code is executed one time only.
if(anul->isDown() == true)
this->close();
What you want is to connect the clicked() signal of the button to a function (slot)
connect(anul, SIGNAL(clicked()), this,SLOT(close()))
I have QTableWidget in my Qt application, and I add buttons to it like that:
QPushButton *startButton = new QPushButton("start");
ui->tableWidget_tvConnection->setCellWidget(row, col, startButton);
connect(startButton, SIGNAL(clicked()), this, SLOT(startButtonPressed()));
And when it is pressed I need to get text from it, so I tried this:
void MainWindow::startButtonPressed()
{
...
QPushButton *button = ui->tableWidget_tvConnection->cellWidget(row, col);
qDebug() << button->text();
}
But compiler doesn't allow me to convert from QWidget* to QPushButton*:
error: invalid conversion from 'QWidget*' to 'QPushButton*' [-fpermissive]
So Is it even possible to get text from button inside QTableWidget?
If it isn't I have another way how to handle this in my application, but this would be really nice.
You get QWidget, so you should cast it to QPushButton. After that, you will be able to use this as a normal pushbutton. Try this:
QPushButton *button = qobject_cast<QPushButton *>(ui->tableWidget_tvConnection->cellWidget(row, col));
if(button) {
//success
} else {
//bad
}
I've made some QPushbuttons like QPushButton **btn and I want to know when the user clicks on one of them using QMouseEvent here is the code but this idea does not work at all any ideas??
void Game::mousePressEvent(QMouseEvent *ev)
{
if(ev->button() == Qt::LeftButton)
{
btn[ev->x()][ev->y()].setStyleSheet("background-color : black;");
}
else
{
btn[ev->x()][ev->y()].setStyleSheet("background-color : red;");
}
that else part is for right click
and here is the code that generates the buttons
void Game::MakeButton()
{
btn = new ApButton*[column];
hrztl = new QHBoxLayout[column];
hrztl->setSpacing(0);
for(int i=0; i<column;i++)
{
btn[i] = new ApButton[row];
for(int j=0; j<row; j++)
{
btn[i][j].setRowCol(i,j);
btn[i][j].setFixedSize(50,50);
hrztl[i].addWidget(&btn[i][j]);
}
ui->MainLayout->addLayout(&hrztl[i]);
}
ui->MainLayout->setSpacing(0);
}
ApButton is a class that inherits QPushButton
This is a good example of use for a QSignalMapper, as seen there: http://qt-project.org/doc/qt-5.0/qtcore/qsignalmapper.html#details
ButtonWidget::ButtonWidget(QStringList texts, QWidget *parent)
: QWidget(parent)
{
signalMapper = new QSignalMapper(this);
QGridLayout *gridLayout = new QGridLayout;
for (int i = 0; i < texts.size(); ++i) {
QPushButton *button = new QPushButton(texts[i]);
connect(button, SIGNAL(clicked()), signalMapper, SLOT(map()));
signalMapper->setMapping(button, texts[i]);
gridLayout->addWidget(button, i / 3, i % 3);
}
connect(signalMapper, SIGNAL(mapped(QString)),
this, SIGNAL(clicked(QString)));
setLayout(gridLayout);
}
In that example, every button is identified by its title, as a QString. The mapper allows you to retrieve the corresponding button's title when one of them is clicked.
Switch your
Game::mousePressEvent(QMouseEvent *e)
to
ApButton::mousePressEvent(QMouseEvent *e)
since you are trying to implement the Press Event of the Button. If you only want to have the moment of the button being pressed and not changing Button behaviour with this, use a SIGNAL/SLOT connection instead of reimplementing the event (add to your creation):
connect(btn[i][j], SIGNAL(pressed()), this, SLOT(slotButtonPressed());
void Game::slotButtonPressed(){
//doSomething
}
use a QButtonGroup or the QSignalMapper if you need to identify more then one Button in a single method or use QObject::sender(), but this can be tricky sometimes.
I had a similar situations some times ago.. I had a QDialog and I had to dinamically add some QPushButton.. then I need to know on which button the user pressed.. so I needed something like:
connect( btn, SIGNAL( clicked(int) ),
this, SLOT( handle(int) ));
for instance a signal-slot connection with the id of the clicked button and a function for handle the click. The function is the same for each buttons and can handle the specific button because of the id..
Implementing this is quite simple subclassing QPushButton adding an id and a new signal..
Hope it's some help!
If Apbutton inherits QPushButton, why don't connect to clicked()?
then you can call QObject::sender()
On slot:
ApButton *but = dynamic_cast<ApButton*>QObject::sender()
if(but)
{
but->setStyleSheet("background-color : black;");
}
to get the clicked buttonbutton and set its stylesheet