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Signal/Slots doesn't work with QSlider and QDoubleSpinBox

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signals&slotsqsliderqdoublespinbox
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  • ? A Former User

    @mrjj
    QObject::connect: No such slot ResizeImageDialog::hightChanged(double) in ..\TextPad\PagesTextEdit.h:167
    QObject::connect: No such slot QDoubleSpinBox::setValue(int) in ..\TextPad\PagesTextEdit.h:168
    yes: false

    mrjjM Offline
    mrjjM Offline
    mrjj
    Lifetime Qt Champion
    wrote on last edited by
    #6

    @HenrikSt.
    Says it cant see the slot function
    ResizeImageDialog::hightChanged

    check spelling etc.

    ? 1 Reply Last reply
    0
    • mrjjM mrjj

      @HenrikSt.
      Says it cant see the slot function
      ResizeImageDialog::hightChanged

      check spelling etc.

      ? Offline
      ? Offline
      A Former User
      wrote on last edited by
      #7

      @mrjj
      hightChanged is not important.

      The Code under that -> QDoubleSpinBox::setValue(int)

      mrjjM 1 Reply Last reply
      0
      • ? A Former User

        @mrjj
        hightChanged is not important.

        The Code under that -> QDoubleSpinBox::setValue(int)

        mrjjM Offline
        mrjjM Offline
        mrjj
        Lifetime Qt Champion
        wrote on last edited by
        #8

        @HenrikSt.
        well check spelling and parameters.

        ? 2 Replies Last reply
        0
        • mrjjM mrjj

          @HenrikSt.
          well check spelling and parameters.

          ? Offline
          ? Offline
          A Former User
          wrote on last edited by
          #9

          @mrjj
          From valueChanged and setValue?

          1 Reply Last reply
          0
          • mrjjM mrjj

            @HenrikSt.
            well check spelling and parameters.

            ? Offline
            ? Offline
            A Former User
            wrote on last edited by
            #10

            @mrjj
            But the spelling is correct...

            Should i paste the all files in Project or a link to them?

            1 Reply Last reply
            0
            • mrjjM Offline
              mrjjM Offline
              mrjj
              Lifetime Qt Champion
              wrote on last edited by
              #11

              which objects are you trying to bind ?
              show your connect statement after the change to int.

              1 Reply Last reply
              0
              • SGaistS Offline
                SGaistS Offline
                SGaist
                Lifetime Qt Champion
                wrote on last edited by
                #12

                Hi,

                QDoubleSpinBox has no such slot, only setValue(double). Use the new Qt 5 notation for your connection, that will solve your problem.

                i.e.

                connect(sliderHeight, &QSlider::valueChanged, m_hightSpinBox, &QDoubleSpinBox::setValue);
                

                Interested in AI ? www.idiap.ch
                Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                ? 1 Reply Last reply
                2
                • JKSHJ Offline
                  JKSHJ Offline
                  JKSH
                  Moderators
                  wrote on last edited by
                  #13

                  See http://doc.qt.io/qt-5/signalsandslots-syntaxes.html#type-checking-and-implicit-type-conversions -- it uses exactly QSlider and QDoubleSpinBox in an example, and explains why it "doesn't work" with the old connection style.

                  Qt Doc Search for browsers: forum.qt.io/topic/35616/web-browser-extension-for-improved-doc-searches

                  1 Reply Last reply
                  3
                  • SGaistS SGaist

                    Hi,

                    QDoubleSpinBox has no such slot, only setValue(double). Use the new Qt 5 notation for your connection, that will solve your problem.

                    i.e.

                    connect(sliderHeight, &QSlider::valueChanged, m_hightSpinBox, &QDoubleSpinBox::setValue);
                    
                    ? Offline
                    ? Offline
                    A Former User
                    wrote on last edited by
                    #14

                    @SGaist
                    Thank you, it works!

                    But how can do that:

                    I have a chackbox. If the Checkbox is checked, the two spinboxes are Ratio. If i changed one slider, the other slider changed too. They both are Ratio to each other.

                    Do you understand?

                    1 Reply Last reply
                    0
                    • jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #15

                      Not really. Should both QDoubleSpinbox have the same value if that checkbox is checked?

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                      ? 1 Reply Last reply
                      0
                      • jsulmJ jsulm

                        Not really. Should both QDoubleSpinbox have the same value if that checkbox is checked?

                        ? Offline
                        ? Offline
                        A Former User
                        wrote on last edited by
                        #16

                        @jsulm
                        They should have the value when:

                        1. The Checkbox is checked and
                        2. one slider is dragged. So than both checkboxes have the value from slider

                        U understand?

                        1 Reply Last reply
                        0
                        • jsulmJ Offline
                          jsulmJ Offline
                          jsulm
                          Lifetime Qt Champion
                          wrote on last edited by
                          #17

                          Unfortunately not:
                          First version: "I have a chackbox. If the Checkbox is checked, the two spinboxes are Ratio. If i changed one slider, the other slider changed too. They both are Ratio to each other."

                          Second version: "
                          The Checkbox is checked and
                          one slider is dragged. So than both checkboxes have the value from slider"

                          In the first version you are talking about two spinboxes in the second version you are talking about two checkboxes. Sorry, but I'm lost...
                          And you did not answer my question whether both spinboxes (I assume you really mean spinboxes) should have the same value if one of them is changed while checkbox is checked.

                          https://forum.qt.io/topic/113070/qt-code-of-conduct

                          ? 1 Reply Last reply
                          0
                          • jsulmJ jsulm

                            Unfortunately not:
                            First version: "I have a chackbox. If the Checkbox is checked, the two spinboxes are Ratio. If i changed one slider, the other slider changed too. They both are Ratio to each other."

                            Second version: "
                            The Checkbox is checked and
                            one slider is dragged. So than both checkboxes have the value from slider"

                            In the first version you are talking about two spinboxes in the second version you are talking about two checkboxes. Sorry, but I'm lost...
                            And you did not answer my question whether both spinboxes (I assume you really mean spinboxes) should have the same value if one of them is changed while checkbox is checked.

                            ? Offline
                            ? Offline
                            A Former User
                            wrote on last edited by
                            #18

                            @jsulm
                            Yes, sorry. I mean SpinBoxes...

                            Your Question:

                            Yes, both should have the same value when the ceckbox is checked:

                               if (m_keepRatioCheckBox->isChecked())
                               {
                                  connect(sliderHeight, &QSlider::valueChanged, m_hightSpinBox, &QDoubleSpinBox::setValue);
                                  connect(sliderHeight, &QSlider::valueChanged, m_widthSpinBox, &QDoubleSpinBox::setValue);
                                  connect(sliderWidth, &QSlider::valueChanged, m_hightSpinBox, &QDoubleSpinBox::setValue);
                                  connect(sliderWidth, &QSlider::valueChanged, m_widthSpinBox, &QDoubleSpinBox::setValue);
                               }
                            

                            This won't work..

                            1 Reply Last reply
                            0
                            • jsulmJ Offline
                              jsulmJ Offline
                              jsulm
                              Lifetime Qt Champion
                              wrote on last edited by
                              #19

                              What you could do: if, for example, sliderHeight is changed you do not set m_widthSpinBox directly, but instead you calculate the difference between m_hightSpinBox and its new value and add this difference (which can be negative) to m_widthSpinBox.
                              You will need your own slots for that.

                              https://forum.qt.io/topic/113070/qt-code-of-conduct

                              ? 1 Reply Last reply
                              0
                              • jsulmJ jsulm

                                What you could do: if, for example, sliderHeight is changed you do not set m_widthSpinBox directly, but instead you calculate the difference between m_hightSpinBox and its new value and add this difference (which can be negative) to m_widthSpinBox.
                                You will need your own slots for that.

                                ? Offline
                                ? Offline
                                A Former User
                                wrote on last edited by
                                #20

                                @jsulm
                                Can you make/Show an example, please?

                                1 Reply Last reply
                                0
                                • jsulmJ Offline
                                  jsulmJ Offline
                                  jsulm
                                  Lifetime Qt Champion
                                  wrote on last edited by
                                  #21

                                  I did not test this code:

                                  void MyClass::sliderHeightChanged(int value)
                                  {
                                      double diff = m_heightSpinBox->value - value;
                                      m_heightSpinBox->setValue(value);
                                      m_widthSpinBox->setValue(m_widthSpinBox->value + diff);
                                  }
                                  
                                  void MyClass::sliderWidthChanged(int value)
                                  {
                                  
                                      double diff = m_widthSpinBox->value - value;
                                      m_widthSpinBox->setValue(value);
                                      m_HeightSpinBox->setValue(m_heightSpinBox->value + diff);
                                  }
                                  
                                  if (m_keepRatioCheckBox->isChecked())
                                  {
                                      connect(sliderHeight, &QSlider::valueChanged, this, &MyClass::sliderHeightChanged);
                                      connect(sliderWidth, &QSlider::valueChanged, this, &MyClass::sliderWidthChanged);
                                  }
                                  

                                  https://forum.qt.io/topic/113070/qt-code-of-conduct

                                  ? 3 Replies Last reply
                                  0
                                  • jsulmJ jsulm

                                    I did not test this code:

                                    void MyClass::sliderHeightChanged(int value)
                                    {
                                        double diff = m_heightSpinBox->value - value;
                                        m_heightSpinBox->setValue(value);
                                        m_widthSpinBox->setValue(m_widthSpinBox->value + diff);
                                    }
                                    
                                    void MyClass::sliderWidthChanged(int value)
                                    {
                                    
                                        double diff = m_widthSpinBox->value - value;
                                        m_widthSpinBox->setValue(value);
                                        m_HeightSpinBox->setValue(m_heightSpinBox->value + diff);
                                    }
                                    
                                    if (m_keepRatioCheckBox->isChecked())
                                    {
                                        connect(sliderHeight, &QSlider::valueChanged, this, &MyClass::sliderHeightChanged);
                                        connect(sliderWidth, &QSlider::valueChanged, this, &MyClass::sliderWidthChanged);
                                    }
                                    
                                    ? Offline
                                    ? Offline
                                    A Former User
                                    wrote on last edited by
                                    #22

                                    @jsulm
                                    I have written all the Code for the Dialog in a Header file..

                                    1 Reply Last reply
                                    0
                                    • jsulmJ jsulm

                                      I did not test this code:

                                      void MyClass::sliderHeightChanged(int value)
                                      {
                                          double diff = m_heightSpinBox->value - value;
                                          m_heightSpinBox->setValue(value);
                                          m_widthSpinBox->setValue(m_widthSpinBox->value + diff);
                                      }
                                      
                                      void MyClass::sliderWidthChanged(int value)
                                      {
                                      
                                          double diff = m_widthSpinBox->value - value;
                                          m_widthSpinBox->setValue(value);
                                          m_HeightSpinBox->setValue(m_heightSpinBox->value + diff);
                                      }
                                      
                                      if (m_keepRatioCheckBox->isChecked())
                                      {
                                          connect(sliderHeight, &QSlider::valueChanged, this, &MyClass::sliderHeightChanged);
                                          connect(sliderWidth, &QSlider::valueChanged, this, &MyClass::sliderWidthChanged);
                                      }
                                      
                                      ? Offline
                                      ? Offline
                                      A Former User
                                      wrote on last edited by
                                      #23

                                      @jsulm
                                      Where can i insert your Code?

                                      class ResizeImageDialog : public QDialog
                                      {
                                      Q_OBJECT
                                      
                                      double         m_ratio;
                                      
                                      QLabel         *m_widthLabel;
                                      QLabel         *m_hightLabel;
                                      QDoubleSpinBox *m_widthSpinBox;
                                      QDoubleSpinBox *m_hightSpinBox;
                                      QRadioButton   *m_keepRatioCheckBox;
                                      QPushButton    *m_okButton;
                                      QPushButton    *m_cancelButton;
                                      QSlider        *sliderWidth;
                                      QSlider        *sliderHeight;
                                      QHBoxLayout    *m_widthLayout;
                                      QHBoxLayout    *m_hightLayout;
                                      QHBoxLayout    *m_buttonLayout;
                                      QVBoxLayout    *m_generalLayout;
                                      
                                      
                                      public:
                                      ResizeImageDialog(QWidget * parent = 0, double imageWidth = 100.0, double imageHight = 100.0) : QDialog(parent)
                                      {
                                         m_widthLabel = new QLabel("Breite");
                                         m_hightLabel = new QLabel("Höhe");
                                      
                                         m_widthSpinBox = new QDoubleSpinBox;
                                         m_widthSpinBox->setMaximum(1500);
                                         m_widthSpinBox->setValue(imageWidth);
                                      
                                      
                                         sliderHeight = new QSlider(Qt::Horizontal);
                                         sliderHeight->setMaximum(1500);
                                         sliderHeight->setMinimum(0);
                                      
                                      
                                      
                                      
                                         sliderWidth = new QSlider(Qt::Horizontal);
                                         sliderWidth->setMaximum(1500);
                                         sliderWidth->setMinimum(0);
                                      
                                      
                                         m_hightSpinBox = new QDoubleSpinBox;
                                         m_hightSpinBox->setMaximum(1500);
                                         m_hightSpinBox->setValue(imageHight);
                                      
                                         connect(sliderHeight, &QSlider::valueChanged, m_hightSpinBox, &QDoubleSpinBox::setValue);
                                         connect(sliderWidth, &QSlider::valueChanged, m_widthSpinBox, &QDoubleSpinBox::setValue);
                                      
                                         m_ratio = imageWidth / imageHight;
                                      
                                         m_keepRatioCheckBox = new QRadioButton("Keep ratio", this);
                                         m_keepRatioCheckBox->setChecked(false);
                                      
                                      
                                         if (m_keepRatioCheckBox->isChecked())
                                         {
                                            connect(sliderHeight, &QSlider::valueChanged, m_hightSpinBox, &QDoubleSpinBox::setValue);
                                            connect(sliderHeight, &QSlider::valueChanged, m_widthSpinBox, &QDoubleSpinBox::setValue);
                                            connect(sliderWidth, &QSlider::valueChanged, m_hightSpinBox, &QDoubleSpinBox::setValue);
                                            connect(sliderWidth, &QSlider::valueChanged, m_widthSpinBox, &QDoubleSpinBox::setValue);
                                            m_hightSpinBox->setValue(25.8);
                                         }
                                      
                                         
                                         
                                         
                                         
                                      
                                         m_widthLayout = new QHBoxLayout;
                                         m_widthLayout->addWidget(m_widthLabel);
                                         m_widthLayout->addWidget(m_widthSpinBox);
                                         m_widthLayout->addWidget(sliderWidth);
                                      
                                         m_hightLayout = new QHBoxLayout;
                                         m_hightLayout->addWidget(m_hightLabel);
                                         m_hightLayout->addWidget(m_hightSpinBox);
                                         m_hightLayout->addWidget(sliderHeight);
                                      
                                         m_okButton = new QPushButton("Ok");
                                         connect(m_okButton, SIGNAL(clicked()), this, SLOT(accept()));
                                      
                                         m_cancelButton = new QPushButton("Abbrechen");
                                         connect(m_cancelButton, SIGNAL(clicked()), this, SLOT(reject()));
                                      
                                         m_buttonLayout = new QHBoxLayout;
                                         m_buttonLayout->addStretch();
                                         m_buttonLayout->addWidget(m_okButton);
                                         m_buttonLayout->addWidget(m_cancelButton);
                                      
                                         m_generalLayout = new QVBoxLayout;
                                         m_generalLayout->addLayout(m_widthLayout);
                                         m_generalLayout->addLayout(m_hightLayout);
                                         m_generalLayout->addWidget(m_keepRatioCheckBox);
                                         m_generalLayout->addLayout(m_buttonLayout);
                                         setLayout(m_generalLayout);
                                      
                                         setMaximumSize(500, 300);
                                         resize(350, 100);
                                         setModal(true);
                                         //resize(670,630);
                                         setWindowTitle(tr("Bildgröße ändern"));
                                         setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
                                      }
                                      
                                      static QPair<double, double> getNewSize(QWidget * parent = 0, double imageWidth = 100.0, double imageHight = 100.0)
                                      {
                                         ResizeImageDialog dlg(parent, imageWidth, imageHight);
                                      
                                         dlg.exec();
                                      
                                      
                                      
                                         QPair<double, double> size;
                                         size.first  = dlg.m_widthSpinBox->value();
                                         size.second = dlg.m_hightSpinBox->value();
                                         return size;
                                      }
                                      };
                                      
                                      
                                      #endif // PAGESTEXTEDIT_H
                                      
                                      
                                      

                                      A .cpp file is not there for the dialog

                                      1 Reply Last reply
                                      0
                                      • jsulmJ jsulm

                                        I did not test this code:

                                        void MyClass::sliderHeightChanged(int value)
                                        {
                                            double diff = m_heightSpinBox->value - value;
                                            m_heightSpinBox->setValue(value);
                                            m_widthSpinBox->setValue(m_widthSpinBox->value + diff);
                                        }
                                        
                                        void MyClass::sliderWidthChanged(int value)
                                        {
                                        
                                            double diff = m_widthSpinBox->value - value;
                                            m_widthSpinBox->setValue(value);
                                            m_HeightSpinBox->setValue(m_heightSpinBox->value + diff);
                                        }
                                        
                                        if (m_keepRatioCheckBox->isChecked())
                                        {
                                            connect(sliderHeight, &QSlider::valueChanged, this, &MyClass::sliderHeightChanged);
                                            connect(sliderWidth, &QSlider::valueChanged, this, &MyClass::sliderWidthChanged);
                                        }
                                        
                                        ? Offline
                                        ? Offline
                                        A Former User
                                        wrote on last edited by
                                        #24

                                        @jsulm
                                        Are there other methods for resizing an Image?

                                        Maybe drag the Image in the Corners for resizing?

                                        1 Reply Last reply
                                        0

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