Putting a Panel on top of a JLabel backGround (Java) - java

I've been fruitlessly searching the internet and nothing that people suggest seems to have any effect for me.
I have a JFrame which I'm trying to put a JPanel in. That JPanel ideally would have a JLabel with an imageicon as the background and a set of buttons in its own Jpanel in the foreground. The issue is every type of layout manager I've seen suggested just does not work as advertised for me. The best I've gotten to work so far is this approach:
public MenuBackgroundPanel(AsteroidsFrame frame)
{
this.gameFrame = frame;
this.setLayout(new OverlayLayout(this));
ImageIcon image = new ImageIcon(getClass().getResource("/resources/background1.gif"));
imageLabel = new JLabel(image, JLabel.CENTER);
mp = new MainMenuPanel(gameFrame);
mp.setMaximumSize(new Dimension(300,200));
this.add(mp);
this.add(imageLabel);
this.setVisible(true);
}
Unfortunately, I'm getting really strange alignments and trying to set location on the background (to actually get it to start at the JFrame's (0,0) or moving the button panel just seems to have no effect. Printing the location of each object says they're both at (0,0) but the image I'll link shows this is just not the case. My point is, I've tried things like JLayeredPane or setting the JLabel as the contentpane of the Jframe and making it transparent but nothing seems to do anything. One or the other of the two objects just covers the other completely.
As you can see the objects are not at all aligned.
Could anyone help me with this?

That JPanel ideally would have a JLabel with an imageicon as the background and a set of buttons in its own Jpanel in the foreground
Easiest way for something like this when the child panel is fully contained in the label image is to just set the layout manager of the JLabel and then add your components to the label.
JLabel background = new JLabel( new ImageIcon(...) );
background.setLayout( new GridBagLayout() );
JPanel buttons = new JPanel();
buttons.setOpaque( false );
buttons.add(...);
background.add(buttons, new GridBagConstraints() );
Now the button panel will be centered on the label.
As you can see the objects are not at all aligned
If you want to use the OverlayLayout then you need to play with the alignmentX/Y properties of each component. You would probably want to set them both to .5. Check out: Java Layout with Component always in Top Right for an example of how changing these values can affect the layout.

Related

JButton positioning, does not appear

In my code I have a JFrame that opens up a main menu, in that menu you can click options, which will take you to the options menu. On that options menu I want to create a back button that will position itself somewhere in the top left corner of the screen. When I run the program and go to the options menu the JButton does not appear. Something must be wrong with my code. Any help? Below is where I first declare the JButton.
static JButton optionsBackButton = new JButton("<html><font size = 5
color = green>Back</font></html>");
Here is the other part of the code that has to do with the JButton.
//Options Menu
JPanel optionsPanel = new JPanel();
JLabel optionsOptionsTitle = new JLabel("<html><font size = 7 color = blue>Options</font></html>");
JPanel optionsOptionsTitlePanel = new JPanel();
JPanel optionsBackButtonPanel = new JPanel();
optionsPanel.setLayout(null);
optionsBackButton.setBounds(100,100,50,50);
optionsBackButtonPanel.add(optionsBackButton);
optionsOptionsTitlePanel.add(optionsOptionsTitle);
optionsPanel.add(optionsOptionsTitlePanel);
optionsPanel.add(optionsBackButtonPanel);
optionsBackButton.addActionListener(this);
//Add panels to the card
panel.add("Home Screen", homePanel);
panel.add("Options Menu", optionsPanel);
//card.add("Game screen", gamePanel);
cardLayout.show(panel, "HomeScreen");
contentPane.add(panel);
Your problem is stemming from your use of null layouts. Note:
JPanel optionsBackButtonPanel = new JPanel(); // holds the back button
// but never given a size
optionsPanel.setLayout(null); // uh oh,.... bad news
optionsBackButton.setBounds(100,100,50,50); // yes you set the bounds of the button
optionsBackButtonPanel.add(optionsBackButton);
optionsOptionsTitlePanel.add(optionsOptionsTitle);
optionsPanel.add(optionsOptionsTitlePanel);
optionsPanel.add(optionsBackButtonPanel); // again, optionsBackButtonPanel
// has been never given a size or location/bounds
optionsBackButton.addActionListener(this);
So you set the bounds of the button and add it to a JPanel that uses the default FlowLayout, and so the bounds are meaningless. Then you add that JPanel, whose bounds you never set, to a JPanel that uses null layout. So the optionsBackButtonPanel will never show.
Solution: Don't use null layouts, but instead learn and use the layout managers.
While null layouts and setBounds() might seem to Swing newbies like the easiest and best way to create complex GUI's, the more Swing GUI'S you create the more serious difficulties you will run into when using them. They won't resize your components when the GUI resizes, they are a royal witch to enhance or maintain, they fail completely when placed in scrollpanes, they look gawd-awful when viewed on all platforms or screen resolutions that are different from the original one.
Start here: Laying Out Components in a Container Tutorial

Java setOpaque method not working to add panels over the top of others

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

Putting a JLabel on top of a JLabel in Java

I would like to know how to put a JLabel on top of another JLabel at a specific position, in a class that extends JPanel in Java. People have asked for help with this before but the solutions that I found do not satisfy me. I am using GridLayout, here is some of my code:
//imports
public class Game extends JPanel implements MouseListener {
Icon background = new ImageIcon(getClass().getResource("/background.jpg"));
Icon foreground = new ImageIcon(getClass().getResource("/foreground.jpg"));
JLabel backgr = new JLabel(background);
JLabel foregr = new JLabel(foreground);
JFrame frame = new JFrame("Game");
public Game() {
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new GridBagLayout());
backgr.addMouseListener(this);
frame.setLayout(new FlowLayout());
frame.setPreferredSize(new Dimension(200,200));
frame.pack();
frame.setVisible(true);
frame.addMouseListener(this);
backgr.setLayout(new BorderLayout());
frame.add(backgr);
backgr.add(foreground);
}
}
(I have a lot of other methods in this class, such as some mouse stuff, but I don't include them here since they are not relevant to this problem.)
Currently the code almost works as I want, the foreground picture is displayed on top of the background, right in the middle of it. But I would like the foreground picture to be displayed at specific coordinates on the background picture. I thought that if I wanted to display the foreground at coordinates (50, 50), I could say backgr.add(foreground, 50,50), this compiles but returns an error when I run the program. Any tips of what to do? It would be really appreciated.
Edit: I discovered that by saying backgr.setLayout(null), backgr.add(foregr) and then foregr.setLocation(50,50), we can do what I was looking for. But since not using a layout manager is discouraged, I am looking for better solutions, so that I can use the coordinates on the backgr Icon.
People have asked for help with this before but the solutions that I found do not satisfy with me since they require me to set the frame layout to null, but I am using GridBagLayout
The frame is using a GridBagLayout.
You are adding the foreground JLabel, so the background JLabel. The background label can use any layout (including null) that you wish.
the foreground picture is displayed on top of the background, right in the middle of it.
That is because you are using a BorderLayout and are adding the foreground to the CENTER, which is the default when you don't specify a constraint.

JPanel Format Problems

I have a 2 JPanels, 1 a button Panel and one a Graphic Panel. I would like the button panel to situated right below the graphic panel but the button panel cuts off the Graphics Panel in the middle. I've been trying the box layout which seems from discussions seems like the best format for what I am trying to do. Can anyone please give me some advice on my formatting problem.
JFrame canvas = new JFrame("Baseball Strike K");
JFrame canvas = new JFrame ("GraphicBoard");
canvas.setVisible(true);
canvas.setSize(1000,1000);
canvas.setDefaultCloseOperation(EXIT_ON_CLOSE);
//create two panels
//add them to contentPane
//set Layout
JPanel buttonPanel = createButtons();
JPanel mainPanel = new Graphic(); //extends JPanel and writes the paint method
mainPanel.setSize(1000, 1000);
Container content = canvas.getContentPane();
content.setLayout(new BoxLayout(content, BoxLayout.Y_AXIS));
content.add(mainPanel);
content.add(buttonPanel);
mainPanel.setSize(1000, 1000);
The job of the layout manager is to determine the size of the component, so you would never invoke the setSize() method of a components.
Instead you give hints to the layout manager on what the size should be. You would do this by overriding the getPreferredSize() method to return an appropriate value. Also, I would pick a more reasonable size (1000, 1000) is a little big to display on most screens. If you really want your painting area this large then I would add the paint panel to a JScrollPane and then add the scrollpane to the frame.
Try getting your code to work using a BoxLayout. Then I would suggest a better layout manager would be to use a BorderLayout. Then you add the paint panel to the CENTER and the buttons to the SOUTH. Now as you resize the frame the paint panel will be adjusted in size.
canvas.setVisible(true);
Also, the placement of that line of code is wrong. You should add all your components to the frame first, before making the frame visible.

How can I make JFrame resize automatically to display all buttons

I have a simple swing application which consists of a JLabel and three buttons. The three buttons are in their own JPanel which is in a JFrame along with the JLabel. The JPanel uses flowlayout manager to arrange the buttons horizontally and the JFrame uses the BorderLayout manager to arrange the JLabel and JPanel vertically.
My problem is when I launch the application, during the course of use the text on one of the buttons changes which increases its width. However, the window doesn't resize to accomdate this and one of the buttons disappears. I thought about calling pack() again, but the JFrame is a local variable in my constructor, also, I shouldn't have to tell my program to resize, right? I haven't been able to find anything on google or here to help me but there must be a simple solution, what am I missing? Code is below.
playButton = new JButton("Play");
pauseButton = new JButton("Pause");
stopButton = new JButton("Stop");
curTrackLabel = new JLabel("No Track Selected");
JFrame myFrame = new JFrame("MediaPlayer");
myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myFrame.setTitle("MediaPlayer");
myFrame.setLocation(400,300);
JPanel topPanel = new JPanel();
topPanel.setLayout(new BorderLayout());
myFrame.add(topPanel);
JPanel buttonPanel = new JPanel(new FlowLayout());
buttonPanel.add(playButton);
buttonPanel.add(pauseButton);
buttonPanel.add(stopButton);
topPanel.add(buttonPanel, BorderLayout.CENTER);
topPanel.add(curTrackLabel, BorderLayout.NORTH);
playButton.addActionListener(new playButtonHandler());
pauseButton.addActionListener(new pauseButtonHandler());
stopButton.addActionListener(new stopButtonHandler());
myFrame.pack();
myFrame.setVisible(true);
Maybe try
((JFrame)myButton.getTopLevelAncestor()).pack();
Where myButton is the button whose text is modified during execution.
As with learning any GUI software, experimentation is best. Try messing with BorderLayouts with nested JPanels.
Ultimately, you use JPanel with a BorderLayout (Flow Layout is OK but really when resizing the window, it epically fails). See http://download.oracle.com/javase/tutorial/uiswing/layout/border.html to learn more about BorderLayouts.
Now for your layout scheme it should be something along the lines of:
Top Level Container: JFrame
JFrame contains a JPanel (Call this
JPanel 1) with a BorderLayout.
The three buttons should be in a
SEPARATE jPanel (JPanel 2). JPanel
1 should add the three buttons as
BorderLayout.CENTER. In this way,
the window will resize if the button
changes its width and/or hright.
The JLabel should be added as
BorderLayout.LINE_START.
The tutorial at: http://download.oracle.com/javase/tutorial/uiswing/layout/border.html should help you with this. But in general, use the following:
Use JPanel and nest JPanels as necessary
BorderLayout.CENTER will accomodate size changes---this is the key! (Experiment with this)
JFrame should only be used as a top level container (for more complex GUIs, this is true).
If you require more flexibility, check out JGoodies: http://www.jgoodies.com/ . This is more along the lines of creating forms.

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