feat: Add top and bottom button in UserOperationLog page.

src/UserOperationLogForm.h

@@ -19,12 +19,14 @@ protected:
      void showEvent(QShowEvent *aEvent) override;
 
 private:
-	QTableView* table = nullptr;
-	QPushButton* btn = nullptr;
-	LogFileTableModel* model = nullptr;
-	SelectDialog* dialog = nullptr;
-	QVBoxLayout* layout = nullptr;
-	QString selectedDateStr;
+    QTableView* mLogTable = nullptr;
+    QPushButton* mDateButton = nullptr;
+    QPushButton* mTopButton = nullptr;
+    QPushButton* mBottomButton = nullptr;
+    LogFileTableModel* mModel = nullptr;
+    SelectDialog* mSelectDateDialog = nullptr;
+    QVBoxLayout* mLayout = nullptr;
+    QString mSelectedDateStr;
 };