My GUI is invisible until I hover over it?

[creationx]

private void createGUI(){
		  gui = new JFrame("GUI");													
		  gui.setBounds(100, 100, 136, 227);											
		  gui.setVisible(true);															
		  gui.setResizable(false);														
		  JPanel panel = new JPanel();
		  gui.add(panel);
			panel.setBorder(new EmptyBorder(5, 5, 5, 5));
			JLabel lblRockCrabs = new JLabel("ROCK CRABS");
			lblRockCrabs.setFont(new Font("Arial", Font.BOLD, 14));
			lblRockCrabs.setBounds(10, 11, 100, 14);
			panel.add(lblRockCrabs);
			
			JLabel lblFood = new JLabel("Food");
			lblFood.setBounds(45, 94, 30, 14);
			panel.add(lblFood);
			
			JComboBox<String> comboBox_1 = new JComboBox<String>();
			comboBox_1.setBounds(10, 112, 95, 20);
			comboBox_1.addItem("SELECT ONE");
			comboBox_1.addItem("Lobster");
			comboBox_1.addItem("Swordfish");
			comboBox_1.addItem("Shark");
			comboBox_1.addItem("Lobster");
			comboBox_1.addActionListener(e -> foodSelected = comboBox_1.getSelectedItem().toString());
			panel.add(comboBox_1);
			
			JLabel lblVersion = new JLabel("version 1.0");
			lblVersion.setBounds(20, 22, 54, 14);
			panel.add(lblVersion);
			
			JButton btnStartScript = new JButton("START");
			btnStartScript.addActionListener(new ActionListener() {
				public void actionPerformed(ActionEvent e) {
					started = true;
					gui.setVisible(false);
				}
			});
			btnStartScript.setBounds(24, 154, 71, 23);
			panel.add(btnStartScript);
	    }
	

For some reason the GUI is not showing up fully. It pops up with nothing on it, and I have to hover my mouse over it to suddenly make everything show up. Then it acts normally and I can select my options and move on. 

What is happening? I followed two tutorials the best I could, but there is clearly something I missed, as other scripts have no problem.

[Manner]

Move setVisible(true) to the last line.

[Precise]

Add the jpanelto the jframe after you've added all the components to it.

[creationx]

Move setVisible(true) to the last line.

Thanks, this fixed it!