Hey there! Let's troubleshoot why your custom popup isn't showing up when you click the button. Here are the most common fixes and checks to get it working:

1. Ensure the Button's Click Signal is Connected to Your Slot #

Qt relies on its signal-slot mechanism to trigger actions—if this connection is missing or broken, your button_is_pushed() function will never run.

• If using Qt Designer:
  Right-click your button → Go to "Go to slot..." → Select clicked(), and make sure the generated slot matches your button_is_pushed() method (or move your code into the generated slot).
• If connecting via code:
  Add this line to your MainWindow constructor (replace ui->yourButton with your actual button object name):

  connect(ui->yourButton, &QPushButton::clicked, this, &MainWindow::button_is_pushed);
  

2. Verify Your Popup Class is Implemented Correctly #

Your pop_up_create_analyse class needs to properly inherit from a Qt window widget (like QDialog for popups) and initialize correctly:

Example Popup Class Implementation: #

Header file (pop_up_create_analyse.h):

#ifndef POP_UP_CREATE_ANALYSE_H
#define POP_UP_CREATE_ANALYSE_H

#include <QDialog>

class pop_up_create_analyse : public QDialog
{
    Q_OBJECT // Required for Qt's meta-object system
public:
    explicit pop_up_create_analyse(QWidget *parent = nullptr);
};

#endif // POP_UP_CREATE_ANALYSE_H

CPP file (pop_up_create_analyse.cpp):

#include "pop_up_create_analyse.h"
#include <QLabel>
#include <QVBoxLayout>

pop_up_create_analyse::pop_up_create_analyse(QWidget *parent) : QDialog(parent)
{
    // Add content to your popup so it's not empty/invisible
    QVBoxLayout* layout = new QVBoxLayout(this);
    QLabel* infoLabel = new QLabel("Custom Popup Content Here!", this);
    layout->addWidget(infoLabel);

    setWindowTitle("My Popup");
    resize(300, 150); // Set a visible size
}

3. Check Your Slot's Accessibility #

Your button_is_pushed() method must be declared in a slots block in your MainWindow header file—Qt needs this to recognize it as a valid slot:

class MainWindow : public QMainWindow
{
    Q_OBJECT
public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

private slots: // This block is mandatory
    void button_is_pushed();

private:
    Ui::MainWindow *ui;
};

4. Debug to Confirm the Slot is Triggered #

Add a debug message to your slot to verify it's being called:

void MainWindow::button_is_pushed() {
    qDebug() << "Button clicked! Attempting to show popup..."; // Check console for this output
    pop_up_create_analyse* create_device_widget = new pop_up_create_analyse(this);
    create_device_widget->show();
    
    // If show() doesn't work, try modal execution (blocks main window until closed):
    // create_device_widget->exec();
}

• If the debug message doesn't appear: Your signal-slot connection is broken—go back to step 1.
• If it does appear: Your popup class is likely missing content or proper initialization (refer to step 2).

Final Check: Rebuild with qmake #

If you added the Q_OBJECT macro or new classes recently, right-click your project in Qt Creator → Select "Run qmake" → Then rebuild. Qt's meta-object system needs this to recognize slots and signals correctly.

内容的提问来源于stack exchange，提问作者Rayzzen