Custom push button try

[viniltc]

Hi

I am trying to subclass a QPushButton to add some functionality to the custom push button. I need this push button to detect key board button 'A' pressed and change a label within my MainWindow.

I created mypushbutton class as follows:
.h

// mypushbutton.h
#ifndef MYPUSHBUTTON_H
#define MYPUSHBUTTON_H

#include <QPushButton>
#include <QKeyEvent>

class MyPushButton : public QPushButton {
    Q_OBJECT
public:
    explicit MyPushButton(QWidget *parent = nullptr);

signals:
    void letterAPressed();

protected:
    void keyPressEvent(QKeyEvent *event) override;
};

#endif // MYPUSHBUTTON_H

and .cpp

// mypushbutton.cpp
#include "mypushbutton.h"

MyPushButton::MyPushButton(QWidget *parent) : QPushButton(parent) {

    setFocusPolicy(Qt::ClickFocus);
}

void MyPushButton::keyPressEvent(QKeyEvent *event) {
    if (event->key() == Qt::Key_A) {
        emit letterAPressed();
    } else {
        QPushButton::keyPressEvent(event);
    }
}

and in my mainwindow I set a widget in the form class but I have not manually promoted it to mypushbutton.h but instead I did this:

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QDebug>
#include <QObject>


MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    button = new MyPushButton(ui->widget);

  connect(button, &MyPushButton::letterAPressed, this, &MainWindow::updateLabelText);
    
        ui->widget->setFocus();
}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::updateLabelText()
{
    ui->label->setText("letter A clicked!");
}

I expect if I click on the ui->widget the ui->label change. But I'm not getting anything. Any idea what's wrong here?

[JonB]

@viniltc

    if (event->key() == Qt::Key_A) {
        emit letterAPressed();

So is this hit?

[viniltc]

@JonB hi, It works now! I forgot that I have setFocusPolicy in the mypushbutton class. So I need to click the widget and press A.