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Java button within graphics panel

I'm relatively new to developing GUI's within java so this may well be a stupid question or quite simply not possible to achieve but here we go.
I've created 1 single JPanel with no border layout set up or anything like that and I intended to paint a GUI on top of it using the graphics class. The JPanel is just plain black and then I've drawn a huge box over it leaving the black just as a border, and painted the whole GUI within this white box.
I want to add buttons within that white box GUI as well but I've no idea how. In fact they don't even have to be traditional buttons JButtons, if I could just draw a shape and have that act as a button then add an event handler to just that shape that would work also but I don't know how I'd do that either.
I have so much code for my whole program (it's a school coursework project) that I'm not sure which parts would even be worth sharing to assist with this question since there's so many GUI aspects I've already drawn so I've tried to just explain my issue in words.
Honestly I have no clue what I'm doing so any help would be appreciated.
EDIT: Here's a screenshot of my current GUI with a 'sketch' of how and where I'd like to be able to add buttons.
GUI Image

As with any suitably complex UI, you need to start by breaking it down into manageable chunks, focusing on areas of mutual interaction and functionality.
For example...
Says to me that you have two primary UI elements, the left and the right.
This could easily be established with a GridLayout, but, if the two sides are not equal in width, a GridBagLayout might be more appropriate
The right side to me says simply, JTable. You could place this within a container using a BorderLayout, allowing the table to occupy the CENTER position.
The key information would then a component laid out with either a GridLayout (top and bottom) or a GridBagLayout if the requirements are more complex. This component would then be added to the SOUTH position of the BorderLayout.
Again, this is pretty simple. The primary layout would probably be a BoderLayout, with the title in the NORTH position, the graph in the CENTER and the buttons wrapped in a component in the SOUTH.
You could use either a FlowLayout or GridBagLayout to layout the buttons depending on your how you want them to appear
Recommendations
Have a look at:
Laying Out Components Within a Container
How to Use Tables
And for the "border", I'd recommend you have a look at LineBorder. Take a look at How to use Borders more details

JPanel vs JFrame when animating

I recently did a program which moves an image along the window and forces it to change its direction when it hits the borders. The animation happened within a JPanel class which was then of course added to a JFrame class which contains the main() function. Now my question is why must it be done in this manner. Can't I simply have just the JFrame and use that both as my window and my animation class which moves the image? Is the JFrame incapable of representing animation on it's own.
Regards.

Omar's answer is correct but I thought I might elaborate just a bit:
Though JFrame's are capable of hosting your animation, it is not a typical use of the JFrame. JFrame's are typically the outermost visual container and host one or more other visual containers (such as JPanel). Though there are exceptions, I would consider the JPanel the most flexible and common way to contain your animation (or other GUI 'controls') to leave you flexibility for adding visual features later.
But as Omar points out, either JFrame or JPanel can be used as they are both considered "containers" in Swing. Tying back to my last comment, using a JPanel is a bit more flexible. For instance, you might later want to incorporate your animation into an Applet/JApplet which you might find confusing and/or difficult if you used a JFrame.
I tried to just comment on Omar's answer but I am a new user and it won't let me add comments yet. Therefore, upvotes are appreciated :)

It's just better to use JPanel as you may want multiple Panels in one frame each with different animations.
Yes, you could do it with JFrame as well.

Setting background image and greyed GlassPane in Java (Swing)

I'm struggling with two Java GUI things at the moment.
This is the situation: I'm designing a word game using Swing components. I have a main JFrame where everything is placed (my GUI class extends JFrame). There are two things I want to do:
1st: I would like to set an image as the background image of the main frame, it has to be displayed behind all components. i've searched around but haven't found a working solution. I tried making an extended BackGroundPanel class but when I create an instance of BackGroundPanel I have no idea how to make it the background of the frame... I also haven't find a good way to load in an image from an 'images' directory in my src folder...
2nd: when the program starts the user is greeted with an undecorated JDialog, the main frame needs to be disabled, which I figured out, but I would also like to make it a bit darker. I believe it should be possible with the GlassPane, but I have no idea how to set the GlassPane to cover the panel with one color...
Help will be much appreciated, I don't think I have any helpful code to share, but I think the situation explained above gives a general idea? I would just like someone to get me on track with this so I can further work this out! Thanks!

My Main class extends JFrame and it has a BorderLayout.
Add your BorderLayout to a JPanel having, e.g. GridLayout().
This AnimationTest illustrates painting a background image behind components.
This Translucent example illustrates using an AlphaComposite; see also this AlphaTest.

Well for your first question, you can use a label and set the icon of it:
JLabel lblimage = new JLabel("");
lblimage.setIcon(new ImageIcon(Main.class.getResource("/img/background.png")));
lblimage.setBounds(0, 0, 794, 711); //size of frame
contentPane.add(lblimage); //bottom
contentPane.add(component1); //middle low
contentPane.add(component2); //middle top
contentPane.add(component3); //top
as for your second question.. you could possibly do the same thing, just use an image with a solid color and lower the transparency, and place on top of your other components (not sure on this solution though).

How to add multiple components to a JFrame?

I have a JFrame.
I also have a Box class which extends Component.
This box class has a paint method which makes a filled rectangle.
When I add multiple of these Box components to my JFrame, only the most recently added one is displayed when I call repaint on the JFrame.
I took a look at the layout managers, but I am not sure that's what I want. All I want is to be able to make an animation of whole bunch of rectangles wherever I want on the screen.
(I also tried creating a panel, adding the panel to the JFrame, and then adding all the Box components to the panel. This did not work either).
Thanks in advance!

You have 2 choices.
You can change the layout of your frame:
JFrame frame;
frame.setLayout(new FlowLayout());
Now, if you add more than one box, it will show up on the frame.
The other option is to do what you said you tried. (Adding a panel to the frame)
JPanel pane = new JPanel();
frame.add(pane);
(add the boxes to 'pane')
Also, you should be careful with the sizing of your Box. You will probably want a call to setPreferredSize() somewhere in the creation of the Box. This will tell Java what size to make the box when it is added to the layout.
You should also take a look at the Java Layout Manager Tutorials. There is lots of great info there.
And, one more thing. The reason only one box at a time was being displayed on the frame was because JFrame's layout manager is BorderLayout. And, when you call add on a component that has a BorderLayout, the component is automatically added to the center of the component. Subsequent calls to add will overwrite the center component, leaving only one component in the middle.

You do need to check out other layout managers. JFrame by default uses BorderLayout and without specifying the "place" a component is added, they get added to CENTER. Depending on what you want your UI to look like depends on the layout manager to use. I would suggest maybe using Netbeans GUI builder.
EDIT: Missed the part about what you want to add but the concept is still the same, if you just add these components to the default layout manager, they will get overwritten. Sounds like you may need to do your painting inside of just one of your Box components or create a JPanel and set the layout to null but then you would have to place them explicitly. Really depends on what you want to do with it exactly.

Do your layout on paper first, then read up on Swing layout managers.
Be aware that some Swing components only allow one component to be added to them. I've run across this when using Tabbed panes. Each tab can only accept one control (JPane?) so you have to create a separate panel with a layout to arrange the related controls and then as a unit add the pane to the tab. There are similar arrangements in the Swing library.

You could set the frame layout to null and then use setBounds() to position your boxes exactly where you want.

Thank you for all your answers.
Since I am using my own custom class, Box, I have the ability of setting the position of my the rectangle through the paint method.
I realized my Box class was extending the wrong thing. It should have been extending javax.swing.Jcomponent.
If I now use a panel with an OverlayLayout, add my components to that panel, they all show up properly.

how add different shapes partially on JPanel+image which is on JPanel

My Project is in Java Swing.
I have a JPanel on which I am adding some images with .png extension (which are on JLabels) at center.
Now I want to add a line which will be partially on the JPanel & partially on that image.
Currently when I am adding a line, JPanel shows the line but when I resize the image & drag it to the image, the image hides the line.
What can be done so that the image doesn't hide my line & shows it on image?

You're probably better off drawing the image yourself and drawing the line over the top in the same control. Create a class that extends Canvas and in the paint method write your own code to paint the image and then draw the line.

Another option is to use JLayeredPane instead of JPanel as your main container and place a non-opaque (setOpaque(false)) JPanel on a higher layer
Use JLayeredPane.setLayer(yourPanel, highNumber) and fill your JLayeredPane using something like GridBagLayout or a simple custom LayoutManager.
You can then implement the custom painting on that panel.

You could try using JXLayer and defining a custom LayerUI for it that would draw the lines. These would then appear above the components you need to draw over.
This is a little more advanced and involves using a 3rd party (open source) custom component but will allow you to change you mind about what Swing component you use to render your images later.
I think this article best describes how to achieve what you want.
I've solved many similar issues to this in the past in a variety of ways and none have had the flexibility and maintainability of JXLayer.