Posting a QKeyEvent to a QLineEdit

[cocheci]

I am trying to post a QKeyEvent to a QLineEdit. The line edit seems to receive the event (I have tested this with an event filter), but the character is not displayed in the QLineEdit. Does anyone know why the QLineEdit does not display the character? Here is the code:

main.cpp

#include <QApplication>
#include "TestForm.h"
 
int main(int argc, char *argv[])
{
 
    QApplication app(argc, argv);
 
    TestForm form;    
    form.show();
 
    return app.exec();    
}

#include <QApplication>
#include "TestForm.h"

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

    QApplication app(argc, argv);

    TestForm form;    
    form.show();

    return app.exec();    
}

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TestForm.h

#ifndef TEST_FORM_H
#define TEST_FORM_H
 
#include <QDialog>
 
class QLineEdit;
 
class TestForm : public QDialog
{
    Q_OBJECT
 
public:
    TestForm(QDialog* parent = 0);
 
public slots:    
    void postKeyEvent();
 
private:
    QLineEdit* _line_edit;
};
 
#endif // TEST_FORM_H

#ifndef TEST_FORM_H
#define TEST_FORM_H

#include <QDialog>

class QLineEdit;

class TestForm : public QDialog
{
    Q_OBJECT

public:
    TestForm(QDialog* parent = 0);

public slots:    
    void postKeyEvent();
    
private:
    QLineEdit* _line_edit;
};

#endif // TEST_FORM_H

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TestForm.h

#include <QDialog>
#include <QFrame>
#include <QHBoxLayout>
#include <QPushButton>
#include <QLineEdit>
#include <QSpacerItem>
#include <QVBoxLayout>
#include <QKeyEvent>
#include <QApplication>
 
 
#include "TestForm.h"
 
 
TestForm::TestForm(QDialog* parent)
    : QDialog(parent)
{
    QFrame* frame = new QFrame(this);
    frame->setFrameShape(QFrame::StyledPanel);
    frame->setFrameShadow(QFrame::Raised);
 
    QHBoxLayout* hboxLayout_2 = new QHBoxLayout(frame);
    hboxLayout_2->setSpacing(6);
    hboxLayout_2->setMargin(0);
 
    _line_edit = new QLineEdit(frame);
 
    hboxLayout_2->addWidget(_line_edit);
 
    QPushButton* button = new QPushButton(frame);
    button->setText("Post key event");
 
    hboxLayout_2->addWidget(button);
 
    QObject::connect(button, SIGNAL(clicked()), this, SLOT(postKeyEvent()));
 
 
    QHBoxLayout* hboxLayout = new QHBoxLayout();
    hboxLayout->setSpacing(6);
    hboxLayout->setMargin(0);
 
    QSpacerItem* spacerItem = new QSpacerItem(131, 31, QSizePolicy::Expanding, QSizePolicy::Minimum);
 
    hboxLayout->addItem(spacerItem);
 
    QPushButton* okButton = new QPushButton(this);
    okButton->setText("OK");
 
    hboxLayout->addWidget(okButton);
 
    QPushButton* cancelButton = new QPushButton(this);
    cancelButton->setText("Cancel");
 
    hboxLayout->addWidget(cancelButton);
 
    QVBoxLayout *vboxLayout = new QVBoxLayout(this);
    vboxLayout->setSpacing(6);
    vboxLayout->setMargin(9);
 
    vboxLayout->addWidget(frame);
 
    vboxLayout->addLayout(hboxLayout);
 
    // Connect the button clicked signals to the form slots
    QObject::connect(okButton, SIGNAL(clicked()), this, SLOT(accept()));
    QObject::connect(cancelButton, SIGNAL(clicked()), this, SLOT(reject()));
 
}       
 
 
 
void TestForm::postKeyEvent()
{
 
    QApplication::postEvent(_line_edit,
                            new QKeyEvent(QEvent::KeyPress,
                                          Qt::Key_A,
                                          Qt::NoModifier));
}

#include <QDialog>
#include <QFrame>
#include <QHBoxLayout>
#include <QPushButton>
#include <QLineEdit>
#include <QSpacerItem>
#include <QVBoxLayout>
#include <QKeyEvent>
#include <QApplication>


#include "TestForm.h"


TestForm::TestForm(QDialog* parent)
    : QDialog(parent)
{
    QFrame* frame = new QFrame(this);
    frame->setFrameShape(QFrame::StyledPanel);
    frame->setFrameShadow(QFrame::Raised);

    QHBoxLayout* hboxLayout_2 = new QHBoxLayout(frame);
    hboxLayout_2->setSpacing(6);
    hboxLayout_2->setMargin(0);

    _line_edit = new QLineEdit(frame);

    hboxLayout_2->addWidget(_line_edit);

    QPushButton* button = new QPushButton(frame);
    button->setText("Post key event");

    hboxLayout_2->addWidget(button);

    QObject::connect(button, SIGNAL(clicked()), this, SLOT(postKeyEvent()));

    
    QHBoxLayout* hboxLayout = new QHBoxLayout();
    hboxLayout->setSpacing(6);
    hboxLayout->setMargin(0);
    
    QSpacerItem* spacerItem = new QSpacerItem(131, 31, QSizePolicy::Expanding, QSizePolicy::Minimum);

    hboxLayout->addItem(spacerItem);

    QPushButton* okButton = new QPushButton(this);
    okButton->setText("OK");

    hboxLayout->addWidget(okButton);

    QPushButton* cancelButton = new QPushButton(this);
    cancelButton->setText("Cancel");

    hboxLayout->addWidget(cancelButton);

    QVBoxLayout *vboxLayout = new QVBoxLayout(this);
    vboxLayout->setSpacing(6);
    vboxLayout->setMargin(9);

    vboxLayout->addWidget(frame);

    vboxLayout->addLayout(hboxLayout);

    // Connect the button clicked signals to the form slots
    QObject::connect(okButton, SIGNAL(clicked()), this, SLOT(accept()));
    QObject::connect(cancelButton, SIGNAL(clicked()), this, SLOT(reject()));

}       



void TestForm::postKeyEvent()
{

    QApplication::postEvent(_line_edit,
                            new QKeyEvent(QEvent::KeyPress,
                                          Qt::Key_A,
                                          Qt::NoModifier));
}

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