Hello

I have some forms with input fields that provide warnings to the user when the fields looses focus (if something is wrong of course). To that end I’ve created my own control that inherits from QLineEdit. For this question consider the extremely simple field that will pop a message box whenever focus is lost when there is text in the control. The actual controls have more logic but all are supposed to pop a message box.

Qt Code: 
  1. class test_line_edit : public QLineEdit
  2. {
  3.   Q_OBJECT
  4.  
  5. public:
  6.   test_line_edit(QWidget * parent = 0) : QLineEdit(parent)
  7.   {}
  8.  
  9.   ~test_line_edit(){}
  10.  
  11. protected:  
  12.   virtual void focusOutEvent(QFocusEvent * e)
  13.   {
  14.     if(!text().isEmpty())
  15.     {
  17.       msg.setText(tr("Test"));
  18.       msg.exec();
  19.       setFocus(Qt::OtherFocusReason);
  20.     }
  21.     else
  22.     {
  23.       QLineEdit::focusOutEvent(e);
  24.     }
  25.   }
  26.  
  27. };
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Now say I have a simple form with just one of these controls and a QPushButton. If the user types in the control and then clicks the button the messagebox pops but the button gets stuck being drawn looking like it’s pressed. How can I make that stop? As best I can tell the QPushButton’s pressed signal is getting fired but that is all I can hear from the button. Since these test_line_edit controls are going to be used everywhere on many different forms I’m hoping there is something I can change inside the test_line_edit class that will fix the problem. Running Qt 4.7.0 on Windows using Visual Studio 2010.

I’ve seen this bug and not sure if it’s related since it’s a different platform and I’m not actually holding the button down: http://bugreports.qt.nokia.com/browse/QTBUG-7901

Here’s a full program that demonstrates the problem (warning: some code generated from the VS plugin)

main.h:
Qt Code: 
  1. #include <QtGui/QMainWindow>
  2.  
  3. #include <QtCore/QVariant>
  4. #include <QtGui/QAction>
  5. #include <QtGui/QApplication>
  6. #include <QtGui/QButtonGroup>
  7. #include <QtGui/QHeaderView>
  8. #include <QtGui/QMainWindow>
  9. #include <QtGui/QMenuBar>
  10. #include <QtGui/QPushButton>
  11. #include <QtGui/QStatusBar>
  12. #include <QtGui/QToolBar>
  13. #include <QtGui/QVBoxLayout>
  14. #include <QtGui/QWidget>
  15.  
  16. #include <QLineEdit>
  17. #include <QMessageBox>
  18.  
  19. class test_line_edit : public QLineEdit
  20. {
  21.   Q_OBJECT
  22.  
  23. public:
  24.   test_line_edit(QWidget * parent = 0) : QLineEdit(parent)
  25.   {}
  26.  
  27.   ~test_line_edit(){}
  28.  
  29. protected:  
  30.   virtual void focusOutEvent(QFocusEvent * e)
  31.   {
  32.     if(!text().isEmpty())
  33.     {
  35.       msg.setText(tr("Test"));
  36.       msg.exec();
  37.       //setFocus(Qt::OtherFocusReason);
  38.     }
  39.     else
  40.     {
  41.       QLineEdit::focusOutEvent(e);
  42.     }
  43.  
  44.     QLineEdit::focusOutEvent(e);
  45.   }
  46.  
  47. };
  48.  
  49. QT_BEGIN_NAMESPACE
  50.  
  51. class Ui_btn_drawing_testClass
  52. {
  53. public:
  54.     QWidget *centralWidget;
  55.     QVBoxLayout *verticalLayout;
  56.     test_line_edit *line_edit;
  58.     QMenuBar *menuBar;
  59.     QToolBar *mainToolBar;
  60.     QStatusBar *statusBar;
  61.  
  62.     void setupUi(QMainWindow *btn_drawing_testClass)
  63.     {
  64.         if (btn_drawing_testClass->objectName().isEmpty())
  65.             btn_drawing_testClass->setObjectName(QString::fromUtf8("btn_drawing_testClass"));
  66.         btn_drawing_testClass->resize(167, 127);
  67.         centralWidget = new QWidget(btn_drawing_testClass);
  68.         centralWidget->setObjectName(QString::fromUtf8("centralWidget"));
  69.         verticalLayout = new QVBoxLayout(centralWidget);
  70.         verticalLayout->setSpacing(6);
  71.         verticalLayout->setContentsMargins(11, 11, 11, 11);
  72.         verticalLayout->setObjectName(QString::fromUtf8("verticalLayout"));
  73.         line_edit = new test_line_edit(centralWidget);
  74.         line_edit->setObjectName(QString::fromUtf8("line_edit"));
  75.  
  76.         verticalLayout->addWidget(line_edit);
  77.  
  78.         btn = new QPushButton(centralWidget);
  79.         btn->setObjectName(QString::fromUtf8("btn"));
  80.  
  81.         verticalLayout->addWidget(btn);
  82.  
  83.         btn_drawing_testClass->setCentralWidget(centralWidget);
  84.         menuBar = new QMenuBar(btn_drawing_testClass);
  85.         menuBar->setObjectName(QString::fromUtf8("menuBar"));
  86.         menuBar->setGeometry(QRect(0, 0, 167, 20));
  87.         btn_drawing_testClass->setMenuBar(menuBar);
  88.         mainToolBar = new QToolBar(btn_drawing_testClass);
  89.         mainToolBar->setObjectName(QString::fromUtf8("mainToolBar"));
  90.         btn_drawing_testClass->addToolBar(Qt::TopToolBarArea, mainToolBar);
  91.         statusBar = new QStatusBar(btn_drawing_testClass);
  92.         statusBar->setObjectName(QString::fromUtf8("statusBar"));
  93.         btn_drawing_testClass->setStatusBar(statusBar);
  94.  
  95.         retranslateUi(btn_drawing_testClass);
  96.  
  97.         QMetaObject::connectSlotsByName(btn_drawing_testClass);
  98.     } // setupUi
  99.  
  100.     void retranslateUi(QMainWindow *btn_drawing_testClass)
  101.     {
  102.         btn_drawing_testClass->setWindowTitle(QApplication::translate("btn_drawing_testClass", "btn_drawing_test", 0, QApplication::UnicodeUTF8));
  103.         btn->setText(QApplication::translate("btn_drawing_testClass", "PushButton", 0, QApplication::UnicodeUTF8));
  104.     } // retranslateUi
  105.  
  106. };
  107.  
  108. namespace Ui {
  109.     class btn_drawing_testClass: public Ui_btn_drawing_testClass {};
  110. } // namespace Ui
  111.  
  112. QT_END_NAMESPACE
  113.  
  114. class btn_drawing_test : public QMainWindow
  115. {
  116.     Q_OBJECT
  117.  
  118. public:
  119.   btn_drawing_test(QWidget *parent = 0, Qt::WFlags flags = 0): QMainWindow(parent, flags)
  120.   {
  121.     ui.setupUi(this);
  122.   }
  123.   ~btn_drawing_test(){}
  124.  
  125. private:
  126.     Ui::btn_drawing_testClass ui;
  127.  
  128. protected slots:
  129.   void on_btn_clicked()
  130.   {
  131.     int breakpoint = 5;
  132.   }
  133.   void on_btn_pressed()
  134.   {
  135.     int breakpoint = 5;
  136.   }    
  137.   void on_btn_toggled(bool)
  138.   {
  139.     int breakpoint = 5;
  140.   }
  141. };
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main.cpp:
Qt Code: 
  1. #include <QtGui/QApplication>
  2. #include "main.h"
  3.  
  4.  
  5.  
  6. int main(int argc, char *argv[])
  7. {
  8.     QApplication a(argc, argv);
  9.     btn_drawing_test w;
  10.     w.show();
  11.     return a.exec();
  12. }
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Thank you for your help and please let me know if I can provide any more information.