C++ (Qt)win->layout()->invalidate();win->layout()->activate();
"Before layout activate"QLabel(0x883bc0) QRect(0,0 100x30)QTreeWidget(0x883ef0) QRect(0,0 100x30)QPushButton(0x8c5c40) QRect(0,0 100x30)QPushButton(0x8c89a0) QRect(0,0 100x30) "After layout activate"QLabel(0x883bc0) QRect(10,10 780x13)QTreeWidget(0x883ef0) QRect(10,28 780x519)QPushButton(0x8c5c40) QRect(8,8 380x22)QPushButton(0x8c89a0) QRect(393,8 379x22) "After show"QLabel(0x883bc0) QRect(10,10 780x13)QTreeWidget(0x883ef0) QRect(10,28 780x519)QPushButton(0x8c5c40) QRect(8,8 380x22)QPushButton(0x8c89a0) QRect(393,8 379x22)