I have a class which is custom widget for QTableWidgetItem. Using Qt 4.8 everything was OK, but in Qt 5.2.1 there is a problem.

My widget class:
Qt Code: 
  1. class QTableCalendarWidget: public QWidget
  2. {
  3.     Q_OBJECT
  4. public:
  5.     QTableCalendarWidget(QString ToolTip,bool Ev,bool BDay)
  6.     {
  7.         Date=QDate::fromString(ToolTip,"d/MM/yyyy");
  8.         Event=new QLabel(this);
  9.         Birth=new QLabel(this);
  10.         Label=new QLabel(QString::number(Date.day()),this);
  11.         Add=new QPushButton(this);
  12.         QPixmap w=QPixmap(12,12);
  13.         w.fill(Qt::transparent);
  14.         if(Ev)
  15.         {
  16.             Event->setPixmap(QIcon(":/cal/Ev").pixmap(15));
  17.         }
  18.         else
  19.         {
  20.             Event->setPixmap(w);
  21.         }
  22.         if(BDay)
  23.         {
  24.             Birth->setPixmap(QIcon(":/cal/BDay").pixmap(15));
  25.         }
  26.         else
  27.         {
  28.             Birth->setPixmap(w);
  29.         }
  30.         Label->setAlignment(Qt::AlignHCenter);
  31.         Add->setStyleSheet("QPushButton {border: 0px solid white;}");
  32.         Add->setIcon(QIcon(w));
  33.         Add->setDisabled(true);
  34.         connect(Add,SIGNAL(clicked()),this,SLOT(addIN()));
  35.         QHBoxLayout *Layout=new QHBoxLayout();
  36.         Layout->setSpacing(1);
  37.         Layout->addWidget(Event);
  38.         Layout->addWidget(Birth);
  39.         Layout->addWidget(Label,Qt::AlignHCenter);
  40.         Layout->addWidget(Add);
  41.         this->setLayout(Layout);
  42.     }
  43.     void AddB()
  44.     {
  45.         Add->setEnabled(true);
  46.         Add->setIcon(QIcon(QIcon(":/main/Add").pixmap(12,12)));
  47.     }
  48. private:
  49.     QDate Date;
  50.     QLabel *Event;
  51.     QLabel *Birth;
  52.     QLabel *Label;
  54. private slots:
  55.     void addIN()
  56.     {
  57.         emit addOUT(Date);
  58.     }
  59. signals:
  60.     void addOUT(QDate);
  61. };
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I am setting widget this way:
Qt Code: 
  1. QTableCalendarWidget *Day=new QTableCalendarWidget(Items[i]->toolTip(),Ev,Bd);
  2.             Calendar->setCellWidget(Items[i]->row(),Items[i]->column(),Day);
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Where Items[i] is QTableWidgetItem already added to QTableWidget, with date as a ToolTip.

The appearance:zrzut ekranu2.png

As all of you can see the custom widget is flat. Standard QTableWidgetItem is visible normally.