1 files changed, 30 insertions, 10 deletions

diff --git a/src/widgets/dialogs/qprogressdialog.cpp b/src/widgets/dialogs/qprogressdialog.cpp
index 662504fc25..35a75adea2 100644
--- a/src/widgets/dialogs/qprogressdialog.cpp
+++ b/src/widgets/dialogs/qprogressdialog.cpp
@@ -84,6 +84,7 @@ public:
     void init(const QString &labelText, const QString &cancelText, int min, int max);
     void layout();
     void retranslateStrings();
+    void setCancelButtonText(const QString &cancelButtonText);
     void _q_disconnectOnClose();
 
     QLabel *label;
@@ -178,9 +179,8 @@ void QProgressDialogPrivate::layout()
 
 void QProgressDialogPrivate::retranslateStrings()
 {
-    Q_Q(QProgressDialog);
     if (useDefaultCancelText)
-        q->setCancelButtonText(QProgressDialog::tr("Cancel"));
+        setCancelButtonText(QProgressDialog::tr("Cancel"));
 }
 
 void QProgressDialogPrivate::_q_disconnectOnClose()
@@ -354,6 +354,11 @@ QProgressDialog::~QProgressDialog()
 void QProgressDialog::setLabel(QLabel *label)
 {
     Q_D(QProgressDialog);
+    if (label == d->label) {
+        if (label)
+            qWarning("QProgressDialog::setLabel: Attempt to set the same label again");
+        return;
+    }
     delete d->label;
     d->label = label;
     if (label) {
@@ -411,6 +416,11 @@ void QProgressDialog::setLabelText(const QString &text)
 void QProgressDialog::setCancelButton(QPushButton *cancelButton)
 {
     Q_D(QProgressDialog);
+    if (d->cancel == cancelButton) {
+        if (cancelButton)
+            qWarning("QProgressDialog::setCancelButton: Attempt to set the same button again");
+        return;
+    }
     delete d->cancel;
     d->cancel = cancelButton;
     if (cancelButton) {
@@ -448,19 +458,25 @@ void QProgressDialog::setCancelButtonText(const QString &cancelButtonText)
 {
     Q_D(QProgressDialog);
     d->useDefaultCancelText = false;
+    d->setCancelButtonText(cancelButtonText);
+}
+
+void QProgressDialogPrivate::setCancelButtonText(const QString &cancelButtonText)
+{
+    Q_Q(QProgressDialog);
 
     if (!cancelButtonText.isNull()) {
-        if (d->cancel) {
-            d->cancel->setText(cancelButtonText);
+        if (cancel) {
+            cancel->setText(cancelButtonText);
         } else {
-            setCancelButton(new QPushButton(cancelButtonText, this));
+            q->setCancelButton(new QPushButton(cancelButtonText, q));
         }
     } else {
-        setCancelButton(0);
+        q->setCancelButton(0);
     }
-    int w = qMax(isVisible() ? width() : 0, sizeHint().width());
-    int h = qMax(isVisible() ? height() : 0, sizeHint().height());
-    resize(w, h);
+    int w = qMax(q->isVisible() ? q->width() : 0, q->sizeHint().width());
+    int h = qMax(q->isVisible() ? q->height() : 0, q->sizeHint().height());
+    q->resize(w, h);
 }
 
 
@@ -483,6 +499,10 @@ void QProgressDialog::setBar(QProgressBar *bar)
         qWarning("QProgressDialog::setBar: Cannot set a new progress bar "
                   "while the old one is active");
 #endif
+    if (bar == d->bar) {
+        qWarning("QProgressDialog::setBar: Attempt to set the same progress bar again");
+        return;
+    }
     delete d->bar;
     d->bar = bar;
     int w = qMax(isVisible() ? width() : 0, sizeHint().width());
@@ -507,7 +527,7 @@ bool QProgressDialog::wasCanceled() const
     \property QProgressDialog::maximum
     \brief the highest value represented by the progress bar
 
-    The default is 0.
+    The default is 100.
 
     \sa minimum, setRange()
 */