diff --git a/aboutdialog.cpp b/aboutdialog.cpp
index 419c3ae..8389126 100644
--- a/aboutdialog.cpp
+++ b/aboutdialog.cpp
@@ -137,14 +137,12 @@ SOFTWARE.
         this->close();
     });
 
-    QVBoxLayout * mainLayout = new QVBoxLayout;
+    setLayout(new QVBoxLayout);
 
-    mainLayout->addWidget(m_tabWidget);
-    mainLayout->addWidget(m_buttonBox);
+    layout()->addWidget(m_tabWidget);
+    layout()->addWidget(m_buttonBox);
 
-    this->setLayout(mainLayout);
-    this->setMinimumSize(361, 161); // not sure why it complain "Unable to set geometry"
-    this->resize(520, 350);
+    setMinimumSize(361, 161); // not sure why it complain "Unable to set geometry"
     setWindowFlag(Qt::WindowContextHelpButtonHint, false);
 }
 
@@ -152,3 +150,8 @@ AboutDialog::~AboutDialog()
 {
 
 }
+
+QSize AboutDialog::sizeHint() const
+{
+    return QSize(520, 350);
+}
diff --git a/aboutdialog.h b/aboutdialog.h
index d484562..4fc3bca 100644
--- a/aboutdialog.h
+++ b/aboutdialog.h
@@ -14,7 +14,9 @@ class AboutDialog : public QDialog
     Q_OBJECT
 public:
     explicit AboutDialog(QWidget *parent = nullptr);
-    ~AboutDialog();
+    ~AboutDialog() override;
+
+    QSize sizeHint() const override;
 
 private:
     QTabWidget * m_tabWidget = nullptr;