So I am trying to have a JPanel inside a JScrollPane, which is located directly inside a JFrame, resize so that it is sometimes smaller than the JScrollPane. Problem is that when I try this it, the lesser size seems to be resized to the original size of the JScrollPane. It works fine when I leave it at a larger size. How do I get this to work? Code will be provided if needed.
Wrap you panel in another panel that uses a FlowLayout. This way the outer panel will be resized to fill the viewport of the scroll pane:
JPanel red = new JPanel();
red.setBackground(Color.RED);
red.setPreferredSize( new Dimension(200, 200) );
JPanel outer = new JPanel();
outer.add( red );
add( new JScrollPane(outer) );
Related
I have been researching for 30 minutes on how to automatically resize a JFrame when the elements are too large. I am trying to fit line segments inside the JFrame but it always exceeds the space but does not automatically generate more space.
What should I do?
DrivePanel panel = new DrivePanel(aCar, coordinates);
JFrame application = new JFrame();
application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
application.add(panel);
application.setSize(600,600);
application.setVisible(true);
Example of output:
Some things to consider :
if you are doing custom painting on your panel, remember that the panel's size it's not changed by what you are drawing.
For example, if the "last" point (i mean the point with the biggest values of x and y) is drawn at (1000,1000) coordinates, you should set the preferred size of your panel in order to contain it.
To let your application using the preferred size of your components, you should call application.pack() (where application is your JFrame object) instead of setting size manually.
If your panel is too big to be displayed enterily on your screen, you might add it to a JScrollPane, and then add the scrollpane to your jframe (not the panel itself).
The scrollpane will automatically use scroll bars if your panel can't be fully displayed on your screen.
So consider this small example, based on your code :
DrivePanel panel = new DrivePanel(aCar, coordinates);
JFrame application = new JFrame();
application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panel.setPreferredSize(new Dimension(1000,1000)); // change 1000,1000 with the coordinates you need ...
JScrollPane scrollPane = new JScrollPane(panel);
application.add(scrollPane);
application.pack();
application.setVisible(true);
Hope this helps :)
I'm developing a game called GalaxyWar, and I am trying to make a map selection menu. I found a problem that when I am using a BoxLayout with BoxLayout.Y_AXIS on a JPanel with setAlignmentX(CENTER_ALIGNMENT), the subcomponents (JPanel's) with assigned size, take up the entire height of the panel (all together), instead of the assigned height!
Here is my code:
scrollPane = new JScrollPane();
scrollPane.setBounds(160, 11, 452, 307);
add(scrollPane);
mapContainer = new JPanel();
mapContainer.setAlignmentX(CENTER_ALIGNMENT);
mapContainer.setAlignmentY(JPanel.TOP_ALIGNMENT);
mapContainer.setLayout(new BoxLayout(mapContainer, BoxLayout.Y_AXIS));
scrollPane.setViewportView(mapContainer);
JPanel demoPanel = new JPanel();
demoPanel.setLayout(null);
demoPanel.setBackground(Color.YELLOW);
demoPanel.setSize(50, 100);
mapContainer.add(demoPanel);
I've researched on this for long, but couldn't find any solutions so far.
try to check out
setPreferredSize()
setMaximumSize()
setMinimumSize()
set all 3 to the same value.
If it still doesn't work, you can try to put the panel, of which you are trying to set the size to fixed, inside another panel.
I'm working right now on a project, and I can't find a solution for my problem.
So here is my problem: I have a JFrame, then I add a container JPanel, and I add 2 other JPanel to this container panel , first panel (InputPanel) is for user input, second panel (Board) for displaying the specified algorithm based on the user input.
But the displayed algorithm is too large, so I thought I will add a JScrollPane to the DisplayPanel, but it didn't worked like I thought it would have. Here is a picture, the red rectangle is the area what changed after I added the JScollPane:
Notice that at my Board class I override the paintComponent(Graphics g) to draw the algorithm.
My code in the main frame:
container = new JPanel();
container.setLayout(new BorderLayout());
board = new Board();
container.add(board, BorderLayout.CENTER);
inputPanel = new InputPanel(board);
container.add(inputPanel, BorderLayout.SOUTH);
pane = new JScrollPane(board);
pane.setViewportView(board);
pane.setPreferredSize(new Dimension(700, 0));
container.add(pane, BorderLayout.WEST);
add(container);
My initial plan was to add a horizontal scrollpane to the Board panel. Can somebody post an example code, or point out for my problem pls?
You added the board twice to container. Add the JScrollPane to the center of container, and continue to pass board to the constructor of your JScrollPane. Don't add the board individually to the container if you want to add it via a JScrollPane.
I want to set the size of the JTextPane according to the size of the panel so that when i add other panels, it changes accordingly. But it just gives a small text pane in the center and when i add some text, it's size changes accordingly.
JPanel panel = new JPanel();
JTextPane txt = new JTextPane();
JScrollPane pane = new JScrollPane();
pane.add(txt);
panel.add(pane,BorderLayout.CENTER);
add(pane);
now the jtextpane just appears at the center of the screen like a small box. I want it to appear according to the size of the panel
JPanel uses FlowLayout by default which sizes components according to their preferred sizes. You can use BorderLayout which will use the maximum area possible.
Also using constraints such as BorderLayout.CENTER has no effect unless the container is actually using BorderLayout. Dont add components to the JScrollPane. This will replaces all components within the view of the component. Instead set the JTextPane as the ViewPortView, for example
JPanel panel = new JPanel(new BorderLayout());
JTextPane txt = new JTextPane();
JScrollPane pane = new JScrollPane(txt);
// pane.add(txt); remove
panel.add(pane, BorderLayout.CENTER);
Read:
How to Use BorderLayout
How to Use Scroll Panes
You added pane twice. Add panel to your base (a JFrame?) instead and remember to actually set your JPanel to use BorderLayout.
I've created a JPanel and JScrollPane like so:
JPanel panel = new JPanel();
panel.setPreferredSize(5000, 5000);
JScrollPane scrollPane = new JScrollPane(panel, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS, JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
scrollPanel.getViewport().setBackground(Color.GRAY); //panel is white
I will be using event handlers to dynamically resize the panel. The problem is, sometimes the panel is smaller than the viewport. I'd set the panel's size like this:
panel.setPreferredSize(10, 10); //Just an example
but the panel will never be smaller than the viewport. I tried using
panel.setSize(10, 10);
and i saw a gray flicker (the viewport's background showing through), which indicated that the panel was being sized to what i wanted it to be, but then grew to the viewport's size. How can i stop this?
To control the sizing the view inside a JViewport, let it implement the Scrollable interface. Without, it's always forced to the size of the viewport.