How to solve the compile error when using QLabel to display pictures in QMainWindow

[TravelingLight]

I'm in trouble to display a picture in QMainWindow using QLabel. I even copied the code from tutorial, but the compiler still fails to compile it. It always remind me a QLabel member is not defined.

Here's my code :
-----------------------------------------------------------------
Error Information:
Ui::WindowClass has no member "imageLabel"
---------------------------------------------------------------------
/*Window.h*/
#include <QtWidgets/QMainWindow>
#include <QtWidgets/QLabel>
#include "ui_window.h"

class Window : public QMainWindow {
Q_OBJECT
public:
Window(QWidget *parent = 0) {}
private:
Ui::WindowClass *ui;
QLabel *imageLabel;
};
---------------------------------------------------------------
/*Window.cpp*/
#include "window.h"
#include "ui_window.h"

Window::Window(QWidget *parent) : QMainWindow(parent), ui(new Ui::WindowClass) {
ui->setupUi(this);
QImage image("./Resources/Tree.png");
ui->imageLabel->setPixmap(QPixmap::fromImage(image));
}
-----------------------------------------------------------------
I know the imageLabel member is declared in Window, not in Ui::WindowClass, but how can I fix it?
BTW, I use Qt5 and VS2013

[Radek]

Check the .ui file. The label imageLabel you want to set does not exist in the UI. Redo and remove the QLabel *imageLablel; from the header file. You can also remove the QLabel header (it will be included from ui_window.h).

[TravelingLight]

Check the .ui file. The label imageLabel you want to set does not exist in the UI. Redo and remove the QLabel *imageLablel; from the header file. You can also remove the QLabel header (it will be included from ui_window.h).
Do you mean adding QLabel *imageLabel to ui_window.h file? I think .ui file is edited in Qt Creator Designer. So I added QLabel *imageLabel to ui_window.h file and deleted it in window.h file. The program can pass the compile now, but it doesn't show a window as I expected. Do you know what the problem is?

[Radek]

No. Do not edit .ui files yourself (unless you are fixing Designer's errors). Remove the changes done by yourself, open the .ui. file in the Designer, and check the label. It has a different name, it is not a QLabel, or it is not in the .ui file at all. Fix the label, save, and try again.

[TravelingLight]

Thank you, you answer helps a lot! I added a label in .ui file, using Designer. Also, I found in ui_window.h, there's a declaration: QLabel *label; so I gave up imageLabel and used label instead. Now I can open the window and show the picture.