Re-layout QProgressDialog when setting the cancel button

Setting a cancel button on QProgressDialog more than once caused the layout
to be invalid. The layout was only applied when the dialog resizes or the
style changes, but not when a new cancel button is set.

The solution is to update the layout() before showing the dialog when adopting
new child widgets.

Fixes: QTBUG-19983
Pick-to: 6.0 6.1
Change-Id: Id8fb1ac56e94a9bd97d4559a2e8d4835856fd7d0
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

1 files changed, 24 insertions, 0 deletions

diff --git a/tests/auto/widgets/dialogs/qprogressdialog/tst_qprogressdialog.cpp b/tests/auto/widgets/dialogs/qprogressdialog/tst_qprogressdialog.cpp
index b847315abd..86963ce24a 100644
--- a/tests/auto/widgets/dialogs/qprogressdialog/tst_qprogressdialog.cpp
+++ b/tests/auto/widgets/dialogs/qprogressdialog/tst_qprogressdialog.cpp
@@ -51,6 +51,7 @@ private Q_SLOTS:
     void getSetCheck();
     void task198202();
     void QTBUG_31046();
+    void QTBUG_19983();
     void settingCustomWidgets();
     void i18n();
     void setValueReentrancyGuard();
@@ -210,6 +211,29 @@ void tst_QProgressDialog::QTBUG_31046()
     QCOMPARE(50, dlg.value());
 }
 
+void tst_QProgressDialog::QTBUG_19983()
+{
+    QProgressDialog tempDlg;
+    tempDlg.setRange(0, 0);
+    tempDlg.setLabelText("This is a test.");
+
+    QPushButton *btnOne = new QPushButton("Cancel", &tempDlg);
+    tempDlg.setCancelButton(btnOne);
+    tempDlg.show();
+    QVERIFY(QTest::qWaitForWindowExposed(&tempDlg));
+    const auto btnOneGeometry = btnOne->geometry();
+    QVERIFY(QPoint(0,0) != btnOneGeometry.topLeft());
+
+    tempDlg.cancel();
+    QVERIFY(!tempDlg.isVisible());
+
+    QPushButton *btnTwo = new QPushButton("Cancel", &tempDlg);
+    tempDlg.setCancelButton(btnTwo);
+    tempDlg.show();
+    QVERIFY(QTest::qWaitForWindowExposed(&tempDlg));
+    QCOMPARE(btnOneGeometry, btnTwo->geometry());
+}
+
 void tst_QProgressDialog::settingCustomWidgets()
 {
     QPointer<QLabel> l = new QLabel;