我需要浏览QList<QString>
与 QAbstractSpinBox
.我在找 indexChanged()
或类似的信号,但没有找到。看来我必须在派生类中保留当前索引。但是,我仍然找不到递增/递减请求,也找不到我要连接插槽的递增/递减按钮。我错过了什么吗?
提前谢谢你。
最佳答案
现在,在我看到你想要做什么之后,这是给你的代码:)。
您需要覆盖 virtual void stepBy( int aSteps )
和 virtual StepEnabled stepEnabled() const
函数以达到您的目的。
// 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();
}
关于c++ - QAbstractSpinBox - indexChanged 信号,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/29133949/