I have a JPanel with a vertical BoxLayout, for one element i want to be able to use another BoxLayout which places elements horisontally.
The code will explain what i'm trying to do:
private void prepareGUI() {
setBorder(new EmptyBorder(20, 0, 20, 0));
setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
JLabel lblTitle = new JLabel("Downloading");
lblTitle.setFont(new Font("Arial", Font.PLAIN, 20));
lblTitle.setAlignmentX(Component.CENTER_ALIGNMENT);
add(lblTitle);
Component verticalStrut = Box.createVerticalStrut(20);
add(verticalStrut);
JProgressBar progressBar = new JProgressBar();
progressBar.setStringPainted(true);
progressBar.setBorder(null);
progressBar.setValue(50);
Dimension size = new Dimension(300, 25);
progressBar.setMinimumSize(size);
progressBar.setMaximumSize(size);
progressBar.setPreferredSize(size);
add(progressBar);
BoxLayout textLayout = new BoxLayout(this, BoxLayout.Y_AXIS);
JLabel lblTest_1 = new JLabel("Test 1!");
textLayout.add(lblTest_1);
JLabel lblTest_2 = new JLabel("Test 2!");
textLayout.add(lblTest_2);
add(textLayout);
}
Now obviously this isn't possible as BoxLayout isn't a Container (It even asks for the container to be linked to on construction.
My question is what is the best way to achieve what i want? Should i create another JPanel and put that inside the first JPanel? I was thinking that but it seems a little too complicated, there must be a simpler way?
BoxLayout is not a container, it's a LayoutManager, so, components can't be added to BoxLayout since box layout is not inheriting anything from abstract class Component, it's will add to some container like JPanel or frame's container....
So, it's wrong to say:
textLayout.add(lblTest_1);
Or even
add(textLayout);
Because this method addes a component to the frame's container, and BoxLayout is not a component.
Should i create another JPanel and put that inside the first JPanel?
Except what you did and avoiding null layout, you're free to do anything, as, design is upon to you, as far as I am preferring multiple panels if wanted.
Related
I'm in the process of creating a circuit editor (similar to any regular paint software with a basic menu and a canvas with specifiable dimensions). I am currently trying to transform the previously unscrollable canvas (JPanel) to a scrollable one.
The obvious design error at the moment is that while the scrollbars seem to correctly reflect the internal size of the canvas (which can of course be way bigger than the JFrame), due to the canvas JPanel being added in the CENTER of the BorderLayout of the master panel, it always resizes along with the JFrame.
public final class MainFrame extends JFrame
{
public MainFrame()
{
JPanel menuPanel = new JPanel(new FlowLayout(FlowLayout.LEFT));
// Populate Menu Panel
// ...
JPanel canvasPanel = new JPanel();
canvasPanel.setBackground(Color.white);
Dimension canvasDims = new Dimension(800,600);
canvasPanel.setPreferredSize(canvasDims);
canvasPanel.setMinimumSize(canvasDims);
canvasPanel.setMaximumSize(canvasDims);
JScrollPane canvasScrollPane = new JScrollPane(
canvasPanel,
JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
JPanel masterPanel = new JPanel(new BorderLayout());
masterPanel.add(menuPanel, BorderLayout.NORTH);
masterPanel.add(canvasScrollPane, BorderLayout.CENTER);
setContentPane(masterPanel);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(1200, 700);
setMinimumSize(new Dimension(500, 500));
setLocationRelativeTo(null);
setVisible(true);
}
I've read quite a few posts regarding centering JPanels and scrollbars but with both complexities added together, things might be a bit more complicated as I haven't yet found a solution.
What I'm really trying to achieve is to have the canvas' JPanel fixed in whatever size the user might have specified and centered in the middle as well as the scrollbars behaving as one would expect like in the beloved windows' paint:
How would you go about doing this/fixing my design? Any help would be greatly appreciated!
P.S. Happy new Year :)
JPanel fixed in whatever size the user might have specified and centered in the middle as well as the scrollbars behaving as one would expect
So you need to nest panels so the canvas panel can be displayed at its preferred size, while the parent panel resizes with the size of the frame.
An easy way to do this is with a JPanel that uses a GridBagLayout. Then you add the canvas panel to this panel using the default GridBagConstraints.
So the basic structure of the panels would be:
JPanel canvas = new JPanel();
canvas.setPreferredSize( new Dimension(300, 300) );
canvas.setBackground(Color.RED);
JPanel wrapper = new JPanel( new GridBagLayout() );
wrapper.add(canvas, new GridBagConstraints() );
frame.add(new JScrollPane(wrapper));
Note: there is no need for your "masterPanel". The default layout manager for the content pane of a JFrame is a BorderLayout, so you just add the "menuPanel" and "scrollPane" directly to the frame with the proper BorderLayout constraints.
Okay so before you ask, yes I'm not using any Layout Manager. No, that doesn't make this bad design (as I've seen people in here saying because someone simply didn't use one). The thing is i want the label to always (and I mean always) show over the two buttons (over the gap left by them which makes it impossible to put it as an Icon or a text on the JButton).
JFrame frame = new JFrame("ColorTap");
private void init() {
JButton jb1 = new JButton(""), jb2 = new JButton("-");
JLabel label = new JLabel("TEXT HERE");
label.setForeground(Color.white);
label.setFont(new Font("Arial Bold",Font.ITALIC,30));
label.setBounds(60,249,200,100);
frame.setLayout(null);
jb1.setBounds(0, 0, 300,298);
jb2.setBounds(0, 302, 300, 300);
jb1.setBackground(Color.black);
jb2.setBackground(Color.black);
jb1.setBorderPainted(false);
jb2.setBorderPainted(false);
frame.add(label);
frame.add(jb1);
frame.add(jb2);
frame.setResizable(false);
frame.setSize(300, 628);
frame.setLocation(550, 50);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
After this what's stranger to me is that the button on the bottom stays under the label and not the one on the top... HELP! Thanks
Swing is optimized to paint components in two dimensions. That is it assumes components will never overlap. Overlapping JButtons cause a problem because of the rollover effects which only cause the buttons to be painted, not the label, so the button is painted over the top of the label.
So you need to tell Swing that components do overlap so Swing can make sure components are painted in the proper ZOrder:
JPanel panel = new JPanel()
{
#Override
public boolean isOptimizedDrawingEnabled()
{
return false;
}
};
Now you can set the layout manager of the panel and add your components to the panel and they will be painted properly.
See: How to put a JButton with an image on top of another JButton with an image? for a working example that DOES use layout managers.
I am using BorderLayout in my application. I have a main panel to which I add two JPanels at the center. I want one of them to be transparent.
My code is :
mainPanel = new JPanel();
mainPanel.setLayout(new BorderLayout());
mainPanel.add(getGraphPaneScrollPane(), BorderLayout.CENTER);
mainPanel.add(getSituationPanel(), BorderLayout.CENTER);
Code for these two functions is :
public JScrollPane getGraphPaneScrollPane() {
if (graphPaneScrollPane == null) {
graphPaneScrollPane = new JScrollPane();
graphPaneScrollPane.setViewportView(getGraphEditorPane());
}
return graphPaneScrollPane;
}
private JScrollPane getSituationPanel(){
if(situationPanel == null){
logs.debug("Initializing Situation Panel");
situationPanel = new JScrollPane();
situationLabel = new JLabel("");
situationLabel.setVerticalTextPosition(JLabel.BOTTOM);
situationLabel.setHorizontalTextPosition(JLabel.CENTER);
situationLabel.setVerticalAlignment(JLabel.TOP);
situationLabel.setHorizontalAlignment(JLabel.CENTER);
situationLabel.setBorder(BorderFactory.createTitledBorder(""));
situationLabel.setBackground(Color.WHITE);
situationLabel.setOpaque(true);
situationLabel.setVerticalAlignment(SwingConstants.TOP);
situationPanel.setViewportView(situationLabel);
}
return situationPanel;
}
Now I want situationPanel to be transparent and getGraphPaneScrollPane to be above that in the GUI, because getGraphPaneScrollPane is the canvas, which I use to draw nodes.
I want situationPanel to be transparent and getGraphPaneScrollPane to be above that in the GUI,
The panel that is on top is the panel that needs to be transparent. If the panel on top is opaque then you will never see the panel under the top panel.
So making changes to the layout is the last thing I want.
Well that is what you are going to need to do. You can't just add two panels to one panel and expect it to work the way you want it to. Most Swing layout managers are designed to lay out components in two dimensions, not on top of one another.
Your current code is:
mainPanel.setLayout(new BorderLayout());
mainPanel.add(getGraphPaneScrollPane(), BorderLayout.CENTER);
mainPanel.add(getSituationPanel(), BorderLayout.CENTER);
You could try using the OverlayLayout, it is designed to lay out panels on top of on another. The code should be something like:
JPanel overlay = new JPanel();
overlay.setLayout( new OverlayLayout(overlay) );
overlay.add(getSituationPanel(), BorderLayout.CENTER); // add transparent panel first
overlay.add(getGraphPaneScrollPane(), BorderLayout.CENTER);
mainPanel.setLayout(new BorderLayout());
mainPanel.add(overlay);
Whenever I add my jbutton to my container it's really huge. I thought using the label.setBounds() function would work but it didn't
public Liability_Calculator(String s)
{
super(s);
setSize(325,200);
Color customColor = Color.WHITE;
c = getContentPane();
c.setLayout(new BorderLayout());
//the button
ok = new JButton("OK");
//ok.setSize(50, 50);
//HERE IS WHERE I TRY AND RESIZE!
ok.setBounds(30,30,50,50);
c.add(ok, BorderLayout.SOUTH);
setVisible(true);
}
Suggestions:
You will want to read up on the layout managers to
understand why your GUI is behaving this way
and to see how to use the layout managers to your advantage to create better looking GUI's in an easy way.
You'll also want to avoid setting bounds on any gui components.
For instance, a JPanel uses FlowLayout(FlowLayout.CENTER)) by default, and you can use that to your advantage by placing your ok JButton into a JPanel and then the JPanel into the contentPane:
ok = new JButton("OK");
// ok.setBounds(30, 30, 50, 50);
JPanel southPanel = new JPanel();
southPanel.add(ok);
c.add(southPanel, BorderLayout.SOUTH);
This will change the first image to the second:
I have problem while setting the Jlabel location.
I set the content pane to some JPanel, I created and tried to add my JLabel.
JLabel mainTitle = new JLabel("SomeApp");
mainTitle.setFont(new Font("Arial",2 , 28));
mainTitle.setBounds(0,0, 115, 130);
getContentPane().add(mainTitle);
I want that my JPanel will be on the top left corner on my application and what I am getting is "SomeApp" on the top center.(and not top left).
btw I tried to add JButton the and the I can`t change the width,height,x,y of the JButton.
Swing uses Layout Managers to place the components.
You have to understand how they work to use them effectively. You can set the layout manager to null, and do the layout your self, but is not recommendable because you'll have to keep track of new components each time, and perform layout computation your self when the window moves shrink etc.
Layout managers are a bit hard to grasp at first.
Your windows could be like this:
Using this code:
import javax.swing.*;
import java.awt.Font;
import java.awt.FlowLayout;
class JLabelLocation {
public static void main( String [] args ) {
JLabel mainTitle = new JLabel("SomeApp");
mainTitle.setFont(new Font("Arial",2 , 28));
//mainTitle.setBounds(0,0, 115, 130); //let the layout do the work
JFrame frame = new JFrame();
JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT));// places at the left
panel.add( mainTitle );
frame.add( panel );// no need to call getContentPane
frame.pack();
frame.setVisible( true );
}
}
Where a particular widget ends up in its container depends on the layout manager that it's using. The layout manager determines how to resize and arrange the widgets to make them fit appropriately. Obviously, the default layout for the content pane decided that the top center was the best place to put the JLabel.
If you want to get to not use a layout manager and just place everything yourself (which generally isn't the best way to lay things out btw), then add:
getContentPane().setLayout(null);
Using layouts is usually a better idea since they allow for dynamic resizing of components. Here's how you'd do it with a BorderLayout:
this.getContentPane().setLayout(new BorderLayout());
this.getContentPane().add (new JLabel ("Main title"), BorderLayout.NORTH);
If you want to add something to the right of the label you could create an additionnal panel with it's own layout :
// Create a panel at the top for the title and anything else you might need
JPanel titlePanel = new JPanel (new BorderLayout());
titlePanel.add(new JLabel ("Main title"), BorderLayout.WEST);
// Add the title panel to the frame
this.getContentPane().setLayout(new BorderLayout());
this.getContentPane().add(titlePanel, BorderLayout.CENTER);
Here are some usefull links to get started with layouts:
http://download.oracle.com/docs/cd/E17409_01/javase/tutorial/uiswing/layout/visual.html
http://download.oracle.com/docs/cd/E17409_01/javase/tutorial/uiswing/layout/using.html