I am new to the java (and programming in general) and I am trying to make my very first program. I'm stuck on the same problem for about 5 hours now, so I've decided to ask for help.
Basically I'm trying to make a program (2d game) that has about 20 positions on the board. Each position is either blue (owned by player1), red(owned by player2) or black(not owned by anyone).
The way I'm going about this is in main I've put a method that calls setup game, and then a method that plays game. I am working on the setup game, basically all it does is it makes an object of class Background (extends JPanel, and overrides paintComponent()) and 20 objects of class Position(extends JPanel, and overrides paintComponent()).
So far I'm stuck on putting those Position objects on top of Background object.
When I do:
Background background= new Background();
frame.getContentPane().add(background);
Position position1= new Position;
frame.getContentPane().add(position1);
frame.setVisible(true);
it shows only a circle and no background as I was hoping, if I first add position and then background, I only have background and no circle.
Anyway I'm new to the java and I am still having trouble founding my way around, however I've tried to search for solutions, and I've found many different solutions to this problem (such as adding position to background first, and then adding background to frame, etc.) but I couldn't make any of them to work.
I am aware that the way I am adding them both to frame is (very likely) completely wrong, but I wrote it that way so you would (hopefully) be sure that what I've wrote actually does show you that my code for each of those classes draws something on the screen.
PS: I didn't copy my code here as most of variable and method names aren't in English so it's fairly hard to read, but if you still think its needed, I will add it. Also I'm sorry for my probably stupid question, but I'm kinda hitting a wall here and I've no idea what else to try.
Basically I'm trying to make a program (2d game) that has about 20
positions on the board. Each position is either blue (owned by
player1), red(owned by player2) or black(not owned by anyone).
Painting in Swing by default never returns PreferredSize, is required to override getPreferedSize()
JPanel has implemented FlowLayout in API, this LayoutManager accepting only PreferredSize came from JComponents added to this container
after a.m. changes to post an SSCCE, short, runnable, compilable
Background background= new Background();
frame.getContentPane().add(background);
Position position1= new Position;
frame.getContentPane().add(position1);
A JFrame uses a BorderLayout by default. Also by default when you add a component to a Container that uses a BorderLayout the comopnent is added to the CENTER. Only one comonent can be added to the CENTER so your Position comonent replaces the Background component.
You want to add the Position to the Background and then add the Background to the frame. Something like:
Background background= new Background();
Position position1= new Position;
background.add(position1);
frame.add(background);
Note: there is no need to uses getContentPane() when adding a component to the frame.
The root panel should be a JFrame with a Container class underneath. When you call someRoot.window.container = yourJPanel, that loads the JPanel as the main component view of the JFrame. Note, a JFrame can only hold one JPanel but other JPanels can hold other JPanels. Just as you add the initial JPanel to the JFRam, a JPanel's own container can be another JPanel. Hope this helps.
Like this:
JPanel temp = new JPAnel();
frame.getContentPane().add(temp);
temp.getContentPane().add(new JPanel());
After these additions, there is a command that is illuding me but you call on JFrame to get it to refresh in real time. I think it is something like:
frame.validate(); //thanks #SMT
or something,
Try using something like
jPanelExampleName.validate();
jPanelExampleName.repaint();
after adding your JPanels.
It sounds like you want to use one JFrame and attach JPanels to it. This is how I personally would do it.
Declare your JFrame and JPanels
JFrame frame1 = new JFrame( "App Name");
JPanel panel1 = new JPanel();
JPanel panel2 = new JPanel();
JPanel panel3 = new JPanel();
JPanel panel4 = new JPanel();
Set the Background (I'm using colors but you get the idea)
panel1.setBackground(Color.orange);
panel2.setBackground(Color.orange);
panel3.setBackground(Color.orange);
panel4.setBackground(Color.orange);
Set your layout for the JFrame (I'm using BoxLayout not sure which would be best for you) You can find the best one for you and some sample code here. Also just set the default close operation.
frame1.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
frame1.setLayout( new BoxLayout( frame1.getContentPane(), BoxLayout.Y_AXIS ) );
Then Just attach your JPanels
frame1.add( panel1);
frame1.add( panel2);
frame1.add( panel3);
frame1.add( panel4);
frame1.pack();
frame1.setVisible( true );
This will allow you to use the JPanels you created and then change the colors via other methods.
Related
I am attempting to place two panels over the top of another two panels, so the positions match exactly. This will allow me to then paint over the top of the previous(bottom) panels. The reason for doing this, is that I have implemented a "drag a rectangle" zoom function, so on the panel the user will drag the mouse to draw a rectangle, and then the panel will become filled with the contents of that rectangle. However, I have now decided I would like include a visual representation of the rectangle as the user drags it.
Since I (assume) I cannot draw the rectangle on the bottom panel, since it already has a complicated paint on it anyway, I figured I would be able to draw it onto another panel that I would place on top. (If there is any easier way please shout!)
I am happy I have been able to get the panels into the correct position, using a BorderLayout/GridLayout combo, without the need for absolute positing, however the setOpaque method is not working on any of the three panels I have added. Does anyone know why this is?
Many thanks in advance, code below:
public void initiate() {
JPanel panel1 = new JPanel();
mandPanel mandDisplay = new mandPanel();
juliaPanel juliaDisplay = new juliaPanel();
JPanel detailsPanel = new JPanel();
JPanel bottomDetails = new JPanel();
JPanel panelForDisplays = new JPanel();
JPanel listenerPanelHolder = new JPanel();
JPanel listenerPanel = new JPanel();
JPanel blankPanel = new JPanel();
panelForDisplays.setLayout(new GridLayout(1,2));
detailsPanel.setLayout(new FlowLayout());
bottomDetails.setLayout(new FlowLayout());
panel1.setLayout(new BorderLayout());
panelForDisplays.add(mandDisplay);
panelForDisplays.add(juliaDisplay);
listenerPanelHolder.setOpaque(false);
listenerPanel.setOpaque(false);
blankPanel.setOpaque(false);
listenerPanelHolder.setLayout(new GridLayout(1,2));
listenerPanelHolder.add(listenerPanel);
listenerPanelHolder.add(blankPanel);
panel1.add(detailsPanel,BorderLayout.NORTH);
panel1.add(panelForDisplays,BorderLayout.CENTER);
panel1.add(listenerPanel,BorderLayout.CENTER);
panel1.add(bottomDetails, BorderLayout.SOUTH);
setContentPane(panel1);
setSize(width*2, height);
setResizable(false);
this.addWindowListener(new onClose(savedJulias));
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
PS: A lot of code is omitted to avoid mess, but if anyone thinks they could solve with more code please say! Thanks :)
First off, adding two components at the BorderLayout.CENTER position replaces the first component with the 2nd, and so the 2nd doesn't cover the 1st, it displaces it. As per the BorderLayout API:
Each region may contain no more than one component,...
But having said that, as I understand your problem in greater detail, I think that your best solution is not to use JLayeredPane or to overlay two JPanels. The best solution is in fact to draw directly on the image-displaying JPanel. This is not hard to do, and shouldn't over complicate your code. For example.
You can use JLayeredPane to place one component to the top of the other. You can check this
So, I have been having trouble drawing multiple objects on a JFrame, and I know I need to use Layout managers, so I decided to test it with one object before I do multiple, however when I run this code:
fps = 30;
panel = new JPanel();
frame = new JFrame();
frame.setLayout(new BorderLayout());
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.setSize(400,400);
frame.addKeyListener(new key());
running = true;
update = true;
ball = new Ball(0,0,1);
//panel.setBackground(Color.BLACK);
panel.add(ball);
panel.setVisible(true);
frame.add(panel, BorderLayout.CENTER);
frame.requestFocus();
frame.setVisible(true);
startTime = System.currentTimeMillis();
nothing draws (There is more to the code, i just didnt want to inlcude all of it). However, when I remove the comment and set the background to black, the JFrame turns black. So why is it that it wont draw my Ball object (which i know works) but will change the background? Is there a specific way you need to draw on a JPanel?
panel = new JPanel();
By default a JPanel uses a FlowLayout which respects the size of any component you add to the panel.
ball = new Ball(0,0,1);
I have no idea what the code in your Ball class looks like, but I would guess the preferred size is (0, 0).
You need to override the getPreferredSize() method of your Ball class to return the size of the Ball so that your layout manager can do its job.
Read the section from the Swing tutorial on Custom Painting for more information and working examples.
I know I need to use Layout managers,
The problem with a layout manager in this case is that the layout manager will control the position of the Ball which may or may not be what you want. If you want balls in random positions, then you will need to use a null layout. Then you will need to use the setSize() and setLocation() methods to control each Ball component.
Another option is to do custom painting of all your Balls. In this case you would add an object that you want to paint to an ArrayList. Then the custom painting code would iterate through the object in the list and paint them individually. See Playing With Shapes for ideas on this approach.
I am coding an intense game and have an important question. In this game, thanks to searching and finding the revalidate() method and the repaint() method I have managed to successfully remove a JPanel and place another JPanel in it's place.
However... this is where the problems begin. I am able to do this, but there are multiple (can range from 9 to 729) such JPanels that need to be changed. I am able to do this in the JFrame no problem... however the issue I am currently facing is that although one JPanel is replaced properly, when I do the next one it is also replaced properly. However, after multiple tests I found that when the JFrame is refreshed by dragging it off and back on screen or any other such change the older changed JPanels vanish.
Is there any way that I can make the newly added JPanel's permanently there rather than vanishing if and only if the JFrame is refreshed??
Here is the code:
int a = f%27;
int b = g%27;
int c = a%9;
int d = b%9;
winningletter.setFont(new Font("Times New Roman", Font.BOLD, 17));
miniwin.add(winningletter);
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).removeAll();
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).setLayout(new GridLayout(1,1));
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).add(miniwin);
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).repaint();
metametametaminiminiwincheck[f/3][g/3]=winningletter.getText();
boardChanger(f, g, 4);
WinChecker(s, f,g,3,4,metametametaminiminiwincheck,x);
You should be using CardLayout: The CardLayout class manages two or more components (usually JPanel instances) that share the same display space.
It enables you to flip between panels the pro way. Each JPanel has an ID and you can display it using it.
link:
http://docs.oracle.com/javase/tutorial/uiswing/layout/card.html
Code:
//Where instance variables are declared:
JPanel cards;
final static String BUTTONPANEL = "BUTTONPANEL";
final static String TEXTPANEL = "TEXTPANEL";
//Where the components controlled by the CardLayout are initialized:
//Create the "cards".
JPanel card1 = new JPanel();
JPanel card2 = new JPanel();
//Create the panel that contains the "cards".
cards = new JPanel(new CardLayout());
cards.add(card1, BUTTONPANEL);
cards.add(card2, TEXTPANEL);
Calling the JPanel to display:
CardLayout cl = (CardLayout)(cards.getLayout());
cl.show(cards, BUTTONPANEL);
I found that when the JFrame is refreshed by dragging it off and back
on screen or any other such change the older changed JPanels vanish
Emm... it seems naturally that UI repaint() method is being invoked authomatically after you re-size JFrame etc :)
thanks to searching and finding the revalidate() method and the
repaint() method I have managed to successfully remove a JPanel
It is quite strange you point your code strategy for the graphics2d only :S If you don't need to paint a new UI every time but keep them , as I could get it, inited in the heap not to re-init to set into your JPanel (?which is acting as a canvas)...
Actually, if you want all JPanel(s) be inited at the same time and just get them one by one by some event you can simply use some kind of storage as a Map or List etc, add them all (invisible) to your 'canvas' preferrably FlowLayout manager and make a needed one visible/invisible by an event for example...
Still the major task you trying to achieve is not pretty clear because you do accent Graphics2D so maybe you trying to achieve some another effect ? :S
P.S.
Anyway, it would be better you to show the problem code snippet because your current question contains too less information as for now...
EDIT
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).removeAll();
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).setLayout(new GridLayout(1,1));
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).add(miniwin);
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).repaint();
Ok... so that is how you add component to your canvas... As I can see, the array in Board is static object... I may suggest, you have more than one canvas object(s)? If yes, it is naturally the miniwin(s) vanish because static array cannot have shared access by two invokers at a time; so I may recommend not to use static field in your case... Please read The Java Language Specification for more detailed information
If you have additional question details please comment
Report if that was helpful
I am writing in java some kind of application and i have to place something in front of another objects( in Z order)
I know that that i should use JLayeredPane but in fact i am not very familiar with it.
My idea is to make two JPanel's with different Z-order factors while inserting them to JLayeredPane.
i pasted my code http://www.wklejto.pl/130038
i would be very grateful if you tell me what is wrong because i am doing it for a long of time with no effect.
I don't see anything wrong with this code. Maybe you're trying to paint a transparent (not opaque) JPanel (e.g. with message) on top of the underlying base JPanel.
In that case you should invoke setOpaque(false) on your front JPanel.
JPanel second = new JPanel();
second.setOpaque(false);
second.add(new JLabel("message"));
jlp.add(second, new Integer(300));
JPanels are opaque by default - on the other hand JLabels aren't.
And take a look into tutorial.
BorderLayout does something strange. If I add two panels to a Container with the same constraint (BorderLayout.CENTER for instance), then the first one goes away, even if the second one is deleted or made invisible
It seems as though it would make sense for it to "stack" each element on top of the previous ones.
Is this correct and by design? If so, is there some documentation on it?
Has anyone else been frustrated by it? Have you a solution, such as a custom LayoutManager?
Sample code:
JFrame frame = new JFrame();
frame.setSize(500, 500);
JPanel panel1 = new JPanel();
panel1.setBackground(Color.blue);
frame.getContentPane().add(panel1);
JPanel panel2 = new JPanel();
panel2.setBackground(Color.red);
frame.getContentPane().add(panel2);
panel2.setVisible(false); // Seems like it should allow us to see panel1.
frame.setVisible(true);
This creates and displays a 500x500 blank box.
BorderLayout was simply not designed to do what you want. Separation of responsibility. If you want that behavior you should compose: combine the BorderLayout with a CardLayout. Though for the actual stack behavior, you'll have to code something yourself (or find someone who already has.)
Is this correct and by design?
Yes.
You need to understand the basics of how layout managers work. One of the jobs of the layout manager is to set the "location" and "size" of the components added to the panel. In the case of a BorderLayout it only tracks 5 components so only the last component added to the CENTER is known by the layout manager.
Layout management is not done when components are added to the panel. It is done when the frame is packed, or made visible (or the revalidate() method is invoked) . In this case the blue panel is not part of the components managed by the BorderLayout so its size remains (0, 0), which means there is nothing to paint.
Try changing your code to:
JPanel panel1 = new JPanel();
panel1.setSize(200, 200);
and you will see the blue panel painted at the specified size.
Now try commenting out:
//panel2.setVisible(false);
and you will see both panels. This is because as components are added to the panel they are assigned a ZOrder. Basically the last component added is painted first, which is why the blue panel is painted on top of the red panel. Check out the setComponentZOrder() method of the Container class for more information.
The CardLayout is probably the layout manager you should be using, but you can check out the Overlap Layout as well.