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Weird Swing Glitch?

I don't understand this, I'm currently making a main menu for a game i'm making but for some reason when I hover over a JButton, it flashes up on the top left side of the JFrame. I don't have any mouseAction methods or anything, is it the gif i'm using? I'm not sure...
Here is a screengrab of the error
Here is my code :
import javax.swing.*;
import java.awt.*;
public class MainMenu {
JFrame frame = new JFrame("Frasergatchi");
public void display(){
frame.setSize(400,400);
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setVisible(true);
}
public void addComponents(){
JButton play = new JButton("Play");
JButton instructions = new JButton("Instructions");
JButton exit = new JButton("Exit");
JPanel panel = new JPanel();
paintMenu paintMenu = new paintMenu();
panel.setLayout(new BoxLayout(panel,BoxLayout.Y_AXIS));
frame.add(panel);
play.setAlignmentX(Component.CENTER_ALIGNMENT);
instructions.setAlignmentX(Component.CENTER_ALIGNMENT);
exit.setAlignmentX(Component.CENTER_ALIGNMENT);
panel.add(paintMenu);
panel.add(play);
panel.add(instructions);
panel.add(exit);
}
public class paintMenu extends JPanel{
public void paintComponent(Graphics graphics){
Image dog = new ImageIcon(getClass().getResource("DogMenuImage.gif")).getImage();
graphics.drawImage(dog,170,240,this);
}
}
}

The first statement in the paintComponent() method should always be:
super.paintComponent(g);
to make sure the background gets cleared.
Also:
Don't do I/O in a painting method. Painting methods are for painting only. Read the image in the constructor of your class and same the image in an instance variable.
Class names SHOULD start with an upper case character. Think of all the classes in the JDK and follow the standards.
There is no need to create a custom class to paint the image. Just use a JLabel with an Icon.

Trying to add a JLabel, but it is stuck in the middle of Jframe

I am trying to add a JLabel but the problem is that it is eith stuck in the middle or to the left of the jframe.
Here is my code;
public class test extends JFrame{
public test(){
JLabel text = new JLabel("test")
text.setLocation(100,100);
setTitle("Help me");
setSize(500,500);
add(text);
}
}
public class Runner{
public static void main (String[] args){
test a = new test();
}
}

Every container has a layout manager that set the position and size of the elements it contains according to its own rules. JFrame default layout is BorderLayout, which put things by default on the left.
To position components absolutely, you have to set the layout manager to null and explicitely call repaint() on your JFrame every time you add/remove/modify your components. You also have to set the size of the components, not only their position (use for example setBounds to set them all in one call.
As an example, The following code does what you want:
public class Test extends JFrame {
public Test() {
// remove any layout manager.
setLayout(null);
setTitle("Help me");
setSize(500, 500);
JLabel text = new JLabel("test");
// set size and position of component.
text.setBounds(new Rectangle(100, 100, 200, 200));
// add component.
add(text);
// explicitely call repaint().
repaint();
}
public static void main(String[] args) {
new Test().setVisible(true);
}
}
For more informations, you can look at the Oracle tutorial on working without a layout manager.
Edit: I would still advise you to use normal layout managers to achieve what you want, as positioning everything absolutely is usually a pain.

add(text);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);

JButton and jgraphx wont show up at the same time

I have tried several ways, but still havent found the solution. I have a jgraph in a frame and I want to add a Jbutton in that frame also in a specific location. However I only get one of them when i run the program, because they expand to the whole window. Any ideas how to fix this?
Thanks in advance.
public class GUIquery extends JFrame {
JFrame frame;
static JGraph jgraph;
final mxGraph graph = new mxGraph();
final mxGraphComponent graphComponent = new mxGraphComponent(graph);
public GUIquery() {
super("Test");
GraphD();
imgbtn();
}
public void GraphD() {
Object parent = graph.getDefaultParent();
graph.getModel().beginUpdate();
try {
........
}catch {
........
} finally {
graph.getModel().endUpdate();
}
getContentPane().add(graphComponent);
}
public void imgbtn() {
JPanel jpanel = new JPanel();
jpanel.setSize(100, 100);
jpanel.setLocation(1200, 60);
JButton imgbtn = new JButton("Export as Image");
imgbtn.setSize(100, 100);
imgbtn.setLocation(1200, 60);
jpanel.add(imgbtn);
add(jpanel);
}
public static void main(String[] args) {
GUIquery frame = new GUIquery();
frame.setLayout(null);
frame.pack();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 320);
frame.setVisible(true);
}
}

Don't use null layouts. They inevitably result in trouble.
From your code snippet it is impossible to tell where you want them to be relative to each other, the following puts the button below the graph.
The content pane uses BorderLayout by default. For BorderLayout, you need to use place components at different positions:
// the default position, but it does not hurt to be explicit
add(graph, BorderLayout.CENTER);
...
// and the panel
add(jpanel, BorderLayout.SOUTH);
If the positioning is not what you want, take a look at the visual guide to layout managers to pick the layout manager that suits your needs best.
In the button panel the setLocation() and setSize() calls are useless. The layout manager of the panel is responsible for setting the button's bounds. If the default FlowLayout is not what you want for it, use the guide to pick another for the panel too.

Moving a JLabel's position for every update

I'm learning Swing and I have the following code:
public class SimView {
private JFrame frame;
private JLabel background;
private JPanel car_panel;
public SimView() {
frame = new JFrame("GUI");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 500);
frame.getContentPane().setLayout(null);
background = new JLabel("");
background.setIcon(new ImageIcon(
"C:\\Users\\D__\\Desktop\\background.png"));
background.setBounds(0, 0, 384, 462);
frame.getContentPane().add(background);
frame.setVisible(true);
car_panel = new JPanel();
car_panel.setBounds(175, 430, 16, 21);
car_panel.setVisible(true);
car_panel.setBackground(Color.BLACK);
background.add(car_panel);
MoveCarRunnable carMover = new MoveCarRunnable(car_panel);
}
private static class MoveCarRunnable implements Runnable {
private JPanel car;
MoveCarRunnable(final JPanel car) {
this.car = car;
}
#Override
public void run() {
// Should I call rePaint() on the car_panel here then ?
}
}
What I want to do is to move the JLabel called "car" 's y coordinates for every update to get the effect of it moving by itself i.e. no user interaction. I'm not quite sure how to do this, I suppose I need to have some sort of repaint() method redrawing the position of the JLabel for every update. But how do I get this class to know that it needs to update the position?
Any pointers (links/code) would be appreciated. I want to get the concept of how Swing and its components work in this case, rather than just employing a solution but of course I am interested in a solution so I can study it closer. Thanks
EDIT:
Please see my edit code above

You will have to create a separate Thread that would modify the location of your label and then call validate() and repaint() on the container (frame.getContentPane()). Don't forget to put some sleep() value inside the thread.
However, there would be a better approach to create a separate JPanel. Inside it you would override the paintComponent method or the paint method and there you would draw an image instead of moving JLabels around.

You should better add a JPanel instead of the label to your layout. Choose the dimensions of the JPanel so that it can contain your car in every phase.
Then overwrite the paint method of that panel to position the image on it.

Java GUI - JPanels, JFrames, JButtons

I'm trying to open a window that has both an image and buttons in it. But I can't seem to figure out how to add the button. The image displays great and the menu works fine, but no matter where I add the button (into the JLabel, JPanel, or JFrame), it doesn't ever show...
Main:
public static void main(String[] args) {
GUI myGUI = new GUI();
myGUI.show();
}
GUI class: openImage is called when using the menu. The image then displays, but no button.
private JFrame myFrame;
private JPanel myPanel;
private JLabel myLabel;
public GUI()
{
myFrame = new JFrame();
initializePanel();
}
public void show()
{
myFrame.setSize(600,600);
myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myFrame.addMouseListener(this);
setupMenu(myFrame);
myFrame.setVisible(true);
}
private void initializePanel()
{
myPanel = new JPanel();
myPanel.setPreferredSize(new Dimension(500,500));
//myPanel.setLayout(new BorderLayout());
}
private void openImage(String fileName)
{
try {
myImage = ImageIO.read(new File(fileName));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
myLabel = getJLabel();
JButton button = new JButton("ButtonClick");
button.addActionListener(this);
myFrame.setContentPane(myLabel);
myPanel.add(button);
myFrame.getContentPane().add(myPanel);
myFrame.pack();
myFrame.setSize(600,600);
}
private void setupMenu(JFrame window) {
JMenuBar menubar = new JMenuBar();
JMenu file = new JMenu("File");
JMenuItem open = new JMenuItem("Open");
open.addActionListener(this);
file.add(open);
menubar.add(file);
window.setJMenuBar(menubar);
}

Your main issue is your setting the contentPane to be a JLabel -- don't do this! The contentPane needs to be opaque, needs to be built to be easily used as a Container and in your case, really should be a JPanel. JLabel I believe uses a null layout so it's no surprise that your code shows no button. If you want to show a background image, make have myPanel constructed from an anonymous class that extends JPanel, override the paintComponent method in this class (calling super.paintComonent first in the method), and draw the image in this method. Then you can add components to the contentPane which will now use a FlowLayout (the default for a JPanel) and it will be opaque by default.
Also, if your goal is to swap items displayed in your GUI, use a CardLayout to do the swapping for you as this layout makes swapping components a breeze.

really don't know, depends of method(s) how you are added picture to the JLabel, JPanel, or JFrame, but maybe for simle Container that contains a few, only one-two JComponents is there crazy idea, without side effects, with idea to display picture and to add there JButton:
JLabel is very similair JComponent to the JPanel, and is by default translucent and very simple implements Icon/ImageIcon, then you'll only to call myLabel.setIcon(myPicture)
to the all of JComponents you are/could be able to add another JComponent by using some of LayoutManager (Box, Flow, GridBagLayout)

You tried to set the label as the content pane and then tried to add the panel to that image which doesn't make sanse at all.
Change it so you add the label to the panel and have the panel as content pane:
Like this:

You have this line which is the problem. It doesn't make much sense:
myFrame.setContentPane(myLabel);
Try instead:
myFrame.getContentPane().add(myLabel);