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.
Related
I have a Java desktop application that at certain point shows up a JPanel with a GridBagLayout and others JPanels inside the grid. This JPanel is showed with a certain color. What I want is to export this JPanel to PDF (I'm using iText) with another color.
No problem with the export (the PDF is generated with the JPanel in its original color) but I'm not sure of the right way to go for changing the JPanel color on the PDF.
My first approach was to set the backgroung color of the original JPanel for the color intended to go on the PDF. I have an utilitary class to generate my PDFs with a method that receives a JPanel and on this method, I made jPanel.setBackgroundColor. This works, but the problem (maybe obvious for most) is that it also changed the original JPanel showed on the application. I thought that invoking this method passing the JPanel would be Java pass-by-value. After some reading, I now understand that it is indeed a pass-by-value, but the value of the pointer to the object JPanel, and not really the object, thus changing it's property, also changes the original.
Another approach was to clone the original JPanel. But then noticed the JPanel is not Cloneable. Also thought of recreate the original JPanel over a new JPanel, but it's getting too complex.
So I'd like to have some opinions on which would be the right way to go.
Thank you very much in advance.
Cheers!
One simple, but slightly different solution would be to wrap another panel around your panel before showing it on your GUI and before printing it.
If you use a different Panel for GUI and for printing, you can use two different background colors (and also different other settings).
Of course this is not a strict solution to the stated problem, but probably a rather good workaround.
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).
i wanted to ask, if somebody might have a solution about a problem i face. I am working at an application, which draws an animation - for instance a map with objects moving onto. My problem is, that on top of the drawing, a Jtable, Jlist as well as other Components are also placed.
In my particular example all of those components have been added to the Panel, which holds the map. In result each component gets redrawn as often as good my fps is. Therefore making one of the tables invisible reduces the already high cpu usage of sometimes around 50% to less than 30%.
My question is, how can i avoid calling somewhat static visual contents paintComponent() method, without having the "background" - the map - whited out the menu.
Since the animation redraws permanently the menu is not shown at all, if its separated from the corresponding JPanel.
First thoughts move into following directions:
Clipping - actually not as good as i would like to, since id like to enable moving around the menus.
JLayeredPane - already tried but seemed to turn out, that the paintComponent method of menus still gets called frequently.
JWindow/Internal Frame - had that thought a couple of minutes ago. Having a complete independent container shall be able to handle my regard, or?
I am looking forward, if somebody has an elegant idea, how to fix that and reduce the cpu usage significantly.
Thanks!!
Best regards.
I would create a custom Shape for clip. Use Area class and subtract from the Area all the children components' bounds.
For painting over JComponent(s) placed into JPanel you have look at
JLayer (Java7) based on JXLayer(Java6)
GlassPane, notice all JComponents must be lightweight, otherwise is GlassPane behind heavyweight (J)Components
is possible painting to the JViewport,
EDIT
you have to use Swing Timer for moving with Icon (in the JLabel) placed into JXLayer, GlassPane or JViewport, don't use Runnable#Thread and never, not by using plain Thread.sleep(int)
I have made a Java game, but it is applet based. I want to convert it into a standalone application. Unfortunately I have 0 knowledge of swing/java applications so I'm not exactly sure where to start and how to get what I want.
My main issue is that the game screen is essentially divided into two parts. The "game screen" and what I refer to as the "dashboard". If you can imagine age of empires, star craft, or any other RTS type of game, that's what the layout is.
So what I want is the screen to have its own graphics panel (all the drawing/animation is done with the graphics and image class) that also has scroll bars in it, that way the size of the game isn't limited to the size of your screen. And I want the dashboard to be it's own separate independent panel, which also uses graphics methods. But in the end, both panels are in the same window.
Is there anyway this is possible?
PS: feel free to request any code or screenshots of the game
Edit: if it is possible, how should I go about doing this?
Simple Swing applications usually based on JFrame class. As i understand, whole game is rendered and not using standard components in UI. Then, roughly, almost no difference between JApplet and JFrame classes. If you used specific JApplet methods for loading resources or something similar, almost all of them would easily replaced with counterparts.
You could create a component class (by extending JComponent) and use it to render main game window. And create another one to render dashboard. Then use BorderLayout as layout manager on JFrame, place main window on center and dashboard on any edge.
There are pretty clear HowTo`s on Oracle site:
How to Make Frames and How to Use Panels.
I think Mersenne's answer covers it pretty well, though I'd consider rendering the game play in a BufferedImage and adding that to (an ImageIcon in) a JLabel in a JScrollPane.
I'm coding a simple graphics program in Java.
So, I have 3 classes.
The first class is the GUI w/c extends JFrame, it load the menu bar and panel (drawing class)
The second class is the drawing class, it extends JPanel, and it has simple Graphics commands.
The third class is an animation class, it displays an animation. It also extends JPanel.
So my question is this, how do I display the animation class in the panel of the GUI class. I want it to be displayed instead of drawing class. When I try to place it there, it displays a tiny box beside the drawing class panel. I am not very good at frames and panels. Thank you very much in advance!
All JPanels have a LayoutManager which, rather handily, manages how Components are laid out. The default layout is FlowLayout, which default mode will simply place each component to the right of the last component.
If you want to change the layout to something more useful, there are many options; BorderLayout, GridLayout, GridBag layout are popular ones. Myself, I use MigLayout, an external library which is very powerful :).
As for it appearing small, try manually enforcing the size with setSize(w, h) or setPreferredSize(w, h).
You might want to write
GUIFrame.remove(drawingPanel);
GUIFrame.add(animationPanel);
GUIFrame.pack();
However the behavior may vary if you have other components added to your GUIFrame. It is difficult to help you exactly because you have not posted an SSCCE.
So my question is this, how do I display the animation class in the panel of the GUI class. I want it to be displayed instead of drawing class.
Use a Card Layout.