error message if no file selected

src/ui/view/AddObjectPopUp.java

@@ -1,6 +1,7 @@
 package ui.view;
 
 import java.awt.BorderLayout;
+import java.awt.Component;
 import java.awt.FlowLayout;
 import java.awt.event.*;
 import java.io.*;
@@ -14,6 +15,7 @@ import javax.swing.filechooser.FileNameExtensionFilter;
 import javax.swing.JLabel;
 import javax.swing.JTextField;
 import javax.swing.JList;
+import javax.swing.JOptionPane;
 import javax.swing.SwingConstants;
 
 public class AddObjectPopUp extends JDialog {
@@ -102,7 +104,8 @@ public class AddObjectPopUp extends JDialog {
 				okButton.addMouseListener(new MouseAdapter() {
 					public void mouseClicked(MouseEvent e) {
 						if (!textField_1.getText().equals(filePath)) {
-							fileChooser();
+							Component frame = null;
+							JOptionPane.showMessageDialog(frame, "No image selected!");
 						} else {
 							copieFile();
 						}