QAbstractSpinBox - indexChanged信號

Question

我需要瀏覽QList<QString>和QAbstractSpinBox。我一直在尋找indexChanged()或類似的信號，但沒有找到它。似乎我必須在我的派生類中保存當前的索引。但是，我仍然無法找到遞增/遞減請求，也無法找到連接插槽的遞增/遞減按鈕。我錯過了什麼嗎？

預先感謝您。

Answer 1

現在，經過我看你想做什麼，這裏是你的代碼： ）。

您需要覆蓋virtual void stepBy(int aSteps)和virtual StepEnabled stepEnabled() const函數爲您的目的。

// Header. 
#pragma once 

#include <QAbstractSpinBox> 

class StringSpinBox : public QAbstractSpinBox 
{ 
    Q_OBJECT 

public: 
    StringSpinBox(QWidget* aParent = nullptr); 
    ~StringSpinBox(); 

    void setStrings(const QStringList& aStrings); 

    virtual void stepBy(int aSteps) override; 

protected: 
    virtual StepEnabled stepEnabled() const override; 

private: 
    QStringList m_Strings; 
    int   m_CurrentIndex; 
}; 

// Source. 
#include "StringSpinBox.h" 

#include <QLineEdit> 

StringSpinBox::StringSpinBox(QWidget* aParent /*= nullptr*/) 
    : QAbstractSpinBox(aParent) 
    , m_CurrentIndex(-1) 
{ 
    lineEdit()->setReadOnly(true); 
} 

StringSpinBox::~StringSpinBox() 
{ 
} 

void StringSpinBox::setStrings(const QStringList& aStrings) 
{ 
    m_Strings  = aStrings; 
    m_CurrentIndex = 0; 

    lineEdit()->setText(m_Strings.at(m_CurrentIndex)); 
} 

// virtual override 
void StringSpinBox::stepBy(int aSteps) 
{ 
    m_CurrentIndex += aSteps; 
    m_CurrentIndex = qBound(0, m_CurrentIndex, m_Strings.size() - 1); 
    lineEdit()->setText(m_Strings.at(m_CurrentIndex)); 
} 

// protected virtual override 
QAbstractSpinBox::StepEnabled StringSpinBox::stepEnabled() const 
{ 
    StepEnabled enabled = StepUpEnabled | StepDownEnabled; 
    if (qBound(0, m_CurrentIndex, m_Strings.size() - 1) == 0) 
    { 
     enabled ^= StepDownEnabled; 
    } 
    if (qBound(0, m_CurrentIndex, m_Strings.size() - 1) == m_Strings.size() - 1) 
    { 
     enabled ^= StepUpEnabled; 
    } 
    return enabled; 
} 

// For demo purpose. 
#include "StringSpinBox.h" 

#include <QtWidgets/QApplication> 

int main(int argc, char* argv[]) 
{ 
    QApplication app(argc, argv); 

    StringSpinBox stringSpinBox; 
    stringSpinBox.setStrings(QStringList() << "Foo" << "Bar" << "Pig"); 
    stringSpinBox.show(); 

    return app.exec(); 
} 

Answer 2

您可以重寫事件方法，然後使用lineEdit-> getText（）獲取QLineEdit中的值。

喜歡的東西：

#include <QAbstractSpinBox> 
#include <QLineEdit> 
#include <iostream> 


class mySpin : public QAbstractSpinBox 
{ 

public: 

    void changeEvent(QEvent* e) override 
    { 
     QLineEdit* edit = lineEdit(); 

     //Do something with the string   
     std::cout << edit->text().toStdString() << std::endl; 
    } 
}; 

其他事件來考慮，從文檔中發現here：

virtual void changeEvent (QEvent * event) 
virtual void closeEvent (QCloseEvent * event) 
virtual void contextMenuEvent (QContextMenuEvent * event) 
virtual void focusInEvent (QFocusEvent * event) 
virtual void focusOutEvent (QFocusEvent * event) 
virtual void hideEvent (QHideEvent * event) 
virtual void keyPressEvent (QKeyEvent * event) 
virtual void keyReleaseEvent (QKeyEvent * event) 
virtual void mouseMoveEvent (QMouseEvent * event) 
virtual void mousePressEvent (QMouseEvent * event) 
virtual void mouseReleaseEvent (QMouseEvent * event) 
virtual void paintEvent (QPaintEvent * event) 
virtual void resizeEvent (QResizeEvent * event) 
virtual void showEvent (QShowEvent * event) 
virtual void timerEvent (QTimerEvent * event) 
virtual void wheelEvent (QWheelEvent * event)