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How to make buttons on Java Swing Application when constantly redrawing frames

The simple version is that I'm drawing Graphics2D 60 times a second on a JPanel and it uses the drawstring method to create a bunch of labels. How would I go about making so I can click on those labels and have something happen?
Explanation: As it currently stands I have a system setup that says for every object in the world draw a string to the side (So I can see a list of all objects in the world). This is done with a for loop and the Graphics2D drawstring method.
The JPanel is being updated 60 times a second so this is being redrawn 60 times a second. I want to be able to click on these object labels so I can select the items, how would I go about turning them into buttons?
I messed around with JButton for awhile but it didn't seem to do me any good because whenever I added it the JPanel would go blank and only the button would render (Plus it didn't render to the right size).
More Details:
I use a
for(int I=0; I < sceneObjects.size(); I++) {
}
loop to grab every object in an object ArrayList. Each object has a String variable "Name". Before the loop class I sent an int called YPosition, and for every object the YPosition goes up by 20 so that the labels don't all stack on top of each other. I'm using the g2d.DrawString method to achieve this. But I need to be able to select the object labels.
I apologize if I forgot something in my question, let me know.
For those who are curious, the code looks exactly like this (Can't be compiled as is):
g2d.setFont(new Font("Arial", Font.PLAIN, hierarchyWidth / 26));
g2d.setColor(Color.black);
int oYPos = 20;
// For every object in existence
for(int i=0; i < engine.sceneObjects.activeObjects.size(); i++) {
GameObject theObject = engine.sceneObjects.activeObjects.get(i);
// If the scrollbar is within range of the hierarchy
// (Based on HierarchyHeight so that it's resolution friendly)
if(oYPos >= hierarchyScroll && oYPos < hierarchyScroll + hierarchyHeight) {
// If the object has no parent
if(theObject.transform.parent == null) {
g2d.drawString(theObject.name, hierarchyPosition.x + 5, hierarchyPosition.y + oYPos);
} else { // If the object has a parent
}
}
oYPos += 20;
}
// Track the last oYPos so that the scrollbar can adjust itself accordingly
lastOYPos = oYPos;
My guess would be some sort of class create for each of these labels and a Boolean stored called isSelected, and then rendering the label according to the class, but this seems a bit more complicated than I'd like to do

Gridbag layout or Grid layout?

I am a little new to swing. In order to learn to use the API correctly, I am designing the following project:
The project is a solving block puzzle solver sliding block puzzle similar to the rush-hour puzzles common in toy stores - https://en.wikipedia.org/wiki/Rush_Hour_(board_game) except there is no escape for a special car.
By dragging the blocks from an off board area to the board, the user specifies the starting configuration of the puzzle. The user, in the same way, specifies an ending goal configuration which dictates where some (or all) of the blocks the user specified initially must be at the end of the puzzle - the ending configuration can be specified using only SOME of the blocks, making multiple legal ending configurations.
The algorithm for solving the puzzle is already complete - I just need to design the interface and I am getting stuck. For designing the tray, I used a grid layout. Since blocks need to be entered at certain positions, I need to be able to place blocks in specific cells in the grid and move them around.
A 'block' object has four attributes - its height, width, its top row, and its left most column (ie - each block is addressed by its top left corner).
I used the suggestion here ( https://stackoverflow.com/questions/2510159/can-i-add-a-component-to-a-specific-grid-cell-when-a-gridlayout-is-used ) for the grid layout.
Right now I have only programmed to the point where java reads the puzzle from a .txt file and is supposed to display it on the screen ( I have not designed any user interactablity yet ).
First, here is the code I have written so far.
public class SolverPuzzleGUI extends JFrame {
//Specs from the puzzle.
Board initBoard;
ArrayList<Block> goalBlocks;
LinkedList<Move> moveList;
JLayeredPane layeredpane;
JPanel Board;
Dimension boardsize = new Dimension(400, 500);
JPanel[][] panelHolder = new JPanel[5][4];
public SolverPuzzleGUI(Board startBoard, ArrayList<Block> startGoalBlocks,
LinkedList<Move> startMoveList) {
this.initBoard = startBoard;
this.goalBlocks = startGoalBlocks;
this.moveList = startMoveList;
} // end constructor.
//gives the actual simulation
public void runSimulation() {
// Initalizing the main window.
setSize(500, 600);
setName("Solution");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setMinimumSize(getMinimumSize());
//Using layered pane
layeredpane = new JLayeredPane();
add(layeredpane);
layeredpane.setPreferredSize(boardsize);
layeredpane.setBackground(Color.YELLOW);
layeredpane.setVisible(true);
// adding the game tray
Board = new JPanel();
layeredpane.add(Board, JLayeredPane.DEFAULT_LAYER);
Board.setLayout(new GridLayout(5, 4));
// centering the game tray.
Board.setPreferredSize(boardsize);
Board.setMinimumSize(boardsize);
Board.setMaximumSize(boardsize);
Box box = new Box(BoxLayout.Y_AXIS);
box.add(Box.createVerticalGlue());
box.add(Board);
box.add(Box.createVerticalGlue());
add(box);
//Adding placeholders to the board for creating blocks
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 4; j++) {
panelHolder[i][j] = new JPanel();
panelHolder[i][j].setBackground(Color.DARK_GRAY);
Board.add(panelHolder[i][j]);
layeredpane.setLayer(panelHolder[i][j], JLayeredPane.DEFAULT_LAYER);
panelHolder[i][j].setVisible(false);
} // end 'j' for
} // end 'i' for
ArrayList<Block> initBlocks = initBoard.getBlocks();
//int count = 0; //DEBUG
for (Block block : initBlocks) {
this.drawBlock(block);
//count++;
//if(count > 4) { break; }
} // end 'for'
Board.setBackground(Color.DARK_GRAY);
Board.setVisible(true);
setVisible(true);
} // end 'run'
private void drawBlock(Block block) {
Dimension blockSize = new Dimension(block.getWidth()*100, block.getHeight()*100);
System.out.println(blockSize.width);
System.out.println(blockSize.height);
JPanel screenBlock = new JPanel();
screenBlock.setPreferredSize(blockSize);
screenBlock.setMinimumSize(blockSize);
screenBlock.setMaximumSize(blockSize);
screenBlock.setSize(blockSize);
screenBlock.setBackground(Color.BLUE);
screenBlock.setBorder(BorderFactory.createLineBorder(Color.BLACK));
layeredpane.setLayer(screenBlock, JLayeredPane.MODAL_LAYER);
int leftRow = block.getRow();
int leftCol = block.getColumn();
panelHolder[leftRow][leftCol].setSize(blockSize);
panelHolder[leftRow][leftCol].setVisible(true);
panelHolder[leftRow][leftCol].add(screenBlock);
layeredpane.setLayer(panelHolder[leftRow][leftCol], JLayeredPane.MODAL_LAYER);
screenBlock.setVisible(true);
}// end 'drawBlock'
public static void main(String[] args) {
String file = "C:\\Users\\Tim\\Desktop\\init.from.handout.txt";
String goal = "C:\\Users\\Tim\\Desktop\\goal.2.from.handout.txt";
/*
A SolverPuzzle object is the object which actually solves the algorithm -
when the class is constructed, it takes the file path of the inital
configuration as an input, as well as the file path of the goal
configuration. It has the following fields:
A 'board' object which specifies the inital configuration of the board.
It contains an ArrayList of Block objects(Remember block objects store
the height and width of the block, as well as the address of the
top left corner of block) which specify the starting
blocks, an ArrayList of EmptySpace objects which specify the empty
spaces on the board, an ArrayList of Move objects, which contain
the legal moves of the configuration, and the height and width of
the tray (in this application, the tray will always be 5 x 4).
An ArrayList of Block objects which specify the ending configuration.
A LinkedList of Move objects which specify the shortest possible
list of Moves which brings the configuration to a position which
satisfies the goal position. A Move object has three fields -
The block object being moved, and the row and column of the
top left corner of the block in the new position.
*/
SolverPuzzle test;
try { test = new SolverPuzzle(file, goal); }
catch (IOException ex) {
System.out.println("IOException");
return;
}
Board testBoard = test.getStartBoard();
ArrayList<Block> testGoalBlocks = test.getGoalBlocks();
LinkedList<Move> testMoveSolution = test.getMoveList();
// testing the gui
SolverPuzzleGUI testGUI = new SolverPuzzleGUI(testBoard, testGoalBlocks,
testMoveSolution);
testGUI.runSimulation();
}
} // end class 'SolverPuzzleGUI'
Here's the current output vs desired output.
http://imgur.com/a/ykXXP
So specifically, I have two questions:
1 - Why is the image only showing the top left corners of the blocks instead of the whole block?
2 - Is it better to continue using the GridLayout or switch to GridBagLayout?
Thanks

GridBagLayout would definitely be suitable for want you want to do. For example, you can expand components to envelop more than one column or row - just like what you want to do. Check out the java tutorials for how to use them.
A key point to remember when using GridBagLayoutis that you need to reset the Constraints after each component, assuming that they're unique to that particular component.
Also - I can't discern what you mean by only showing the top-left - it looks likes its showing the whole thing to me...

Java Swing mouseDragged callback speed

I have a question regarding the callback speed of the mouseDragged message of the MouseMotionListener in Java Swing. This post is sort of related but it's not entirely the same so I started a question of my own.
I'm making a small in-house application with no eye on commercial distribution that is basically a digitalized TCG (Trading Card Game) emulator. For any of you familiar with MtG (Magic the Gathering), you might've heard from such a similar program. I'm trying to create something that looks sort of like this, but less fancy.
My GUI consists of a JFrame with menu and then some panels containing various buttons and labels, but I'll only go over the relevent parts to explain my problem.
In essence, I'm using a vertical split JSplitPane with a JPanel on the left, with in that a JScrollPane with a JList in it, which represents at any time the cards in your hand that you can play. On the right side of the split, I have a JLayeredPane with a background image in the DEFAULT_LAYER (subclass of JPanel that overrides the draw function to add an image) and, on various layers above the PALETTE_LAYER, I display the cards that are in play (gathered in an ArrayList) by means of custom CardPanels (another subclass of JPanel that illustrates a card). The entire JLayeredPane is thus a representation of the table in front of you with all the cards you've already played.
I first started by adding a MouseListener and a MouseMotionListener to the JLayeredPane to pick up events, allowing me to register a mouse press, check if this was above a card, then use the mouse dragged event to move the card around and finally mouse release to place it back . This all works perfectly fine and if I add logging information I can see the mouseDragged callback function is called often, allowing for a visually fast dragging motion without lag.
Today I decided to add functionality to allow the user to drag a card from his hand to the "table" (instead of double clicking on the card in the JList), so I added the appropriate listeners to the JList along with filling in some functions like MousePressed and MouseReleased. On a mouse press, I check what card from the list was clicked, I lock the list, create a custom CardPanel (but don't add it anywhere yet, I just allocate and initiate it!) and set a flag. In mouse dragged, I check if this flag is set. If it is, I check where the cursor is. If it is anywhere above the JLayeredPane, I add the CardPanel to the DRAG_LAYER and set another flag. If this second flag is set in successive calls to mouse dragged, I don't add the panel again but I just change the location. This functionality is practically the same as the one in my previous mouse dragged callback. On mouse release, I unlock the list and add the CardPanel on the correct layer in the JLayeredPane.
Everything is working as intended so I'm pretty sure my code is okay, but there is just one slight issue:
When dragging a card from the list to the layered pane (instead of from the layered pane to the layered pane), I notice the mouseDragged callback is called at a pretty low frequency by the JList (approx 10 times per second), introducing some visually disturbing lag (compared to approx 30 times per second in the first case of dragging).
I'm going to add some code snippets as to clarify my problem but I'm afraid adding all the code to allow you to run it yourself would be serious overkill.
The main question in this post is: does anybody know why the mouseDragged is called faster by one MouseMotionListener than by another MouseMotionListener? The listener to the JLayeredPane component makes fast successive calls, the listener to the JList calls significantly slower.
Note: I'm developing in Netbeans and I'm using the built-in graphical Swing Interface Builder. I'm using a JFrame form as my main class.
public class MyFrame extends JFrame{
...
protected JLayeredPane layeredPane;
protected JList cardsInHandList;
...
...
protected ArrayList<String> cardsInHand;
...
private void attachListeners(){
layeredPane.addMouseListener(new MouseAdapter(){
public void MousePressed(MouseEvent e){
// set a flag, start a drag
}
public void MouseReleased(MouseEvent e){
// unset a flag, stop a drag
}
});
layeredPane.addMouseMotionListener(new MouseMotionAdapter(){
public void MouseDragged(MouseEvent e){
// drag the card around
// gets called a lot!
// actual code:
if (e.getButton() == MouseEvent.BUTTON1) {
if (!dragging) return; // the flag
int x = e.getX() - 10;
int y = e.getY() - 10;
// snap to grid
x /= GRIDX;
x *= GRIDX;
y /= GRIDY;
y *= GRIDY;
// redraw the card at its new location
draggedCard.setLocation(x, y);
}
}
});
cardsInHandList.addMouseListener(new MouseAdapter(){
public void MousePressed(MouseEvent e){
// set a flag, start a drag
}
public void MouseReleased(MouseEvent e){
// unset a flag, stop a drag
}
});
cardsInHandList.addMouseMotionListener(new MouseMotionAdapter(){
public void MouseDragged(MouseEvent evt){
// check cursor location, drag if within bounds of layeredPane
// gets called a whole lot less!! _Why?_
// actual code:
if (!draggingFromHand) return; // the flag
// check location of cursor with own method (contains() didn't work for me)
if (isCursorAtPointAboveLayeredPane(evt.getLocationOnScreen())) {
// calculate where and snap to grid
int x = (int) (evt.getLocationOnScreen().getX() - layeredPane.getLocationOnScreen().getX())-10;
int y = (int) (evt.getLocationOnScreen().getY() - layeredPane.getLocationOnScreen().getY())-10;
// snap to grid
x /= GRIDX;
x *= GRIDX;
y /= GRIDY;
y *= GRIDY;
if(!draggingFromHandCardPanelAdded){
layeredPane.add(draggingFromHandCardPanel, JLayeredPane.DRAG_LAYER);
draggingFromHandCardPanelAdded = true;
} else {
draggingFromHandCardPanel.setLocation(x,y);
}
}
}
});
}
I'll try to build a short runnable example reproducing the problem and then attach the code somewhere but right now I got to skoot.
Thanks in advance
PS: I am aware that there is another way to drag in Java, involving TransferHandlers and all that but it just seems like too much hassle and it isn't an actual answer to my question of how come the one callback seems to be called more than the other, so please don't tell me to use that instead.

Once you drag outside the list, Java start generating synthetic mouse events for the list, which might be the cause. See the javadoc for JComponent#setAutoscrolls(boolean).
You might get better results using a global event listener, see
http://tips4java.wordpress.com/2009/08/30/global-event-listeners/

Why won't .validate() update the contentPane in this code?

I'm having trouble with a contentPane. Here's the code in question:
public void graph() {
JFrame frame = new JFrame("Graph");
Graph[] graphs = new Graph[timeSlices];
int k = 0;
for (TreeMap<MyPoint, BigDecimal> prevU : prevUs) {
graphs[k] = new Graph(prevU);
k++;
}
// The KeyList handles switching between graphs.
frame.addKeyListener(new KeyList(frame.getContentPane(), graphs));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(810, 500);
frame.setVisible(true);
}
private class KeyList extends KeyAdapter {
private Container contentPane;
private Graph[] graphs;
private int index;
public KeyList(Container contentPane, Graph[] graphs) {
this.contentPane = contentPane;
this.graphs = graphs;
this.index = 0;
this.contentPane.add(this.graphs[0]);
}
public void keyPressed(KeyEvent e) {
// Go back a time step
if (e.getKeyCode() == KeyEvent.VK_LEFT && index > 0) {
contentPane.remove(graphs[index]);
contentPane.add(graphs[--index]);
contentPane.validate();
System.out.println(index);
}
// Go forward a time step
else if (e.getKeyCode() == KeyEvent.VK_RIGHT && index < timeSlices - 1) {
contentPane.remove(graphs[index]);
contentPane.add(graphs[++index]);
contentPane.validate();
System.out.println(index);
}
// Exit if Esc is hit
else if (e.getKeyCode() == KeyEvent.VK_ESCAPE)
System.exit(0);
}
}
Graph is just a Component, easy peasy. When I hit the right arrow, I want to replace the currently displayed Graph with the next one in the array, and when I hit the left arrow, I want to replace the Graph with the previous one in the array.
The weird thing is that when I hit right, it works just fine. However, when I hit left, the Graph doesn't change. The index changes, thus I know the code is being reached, but the GUI doesn't change.
Now get ready for this. When I comment out the right key's validate line, the left one will work about half the time. What is going on there? Here's the rest of the code if you want to run and see for your self (just one file) : http://pastebin.com/qWxWrypK. The starting paramemters I'm currently using are T=1, dt=.01, L=1, h=.05.
I was looking into it, I thought it might be because the contentPane of a JFrame is really a JPanel, but that line of thinking didn't get anywhere...
Thanks for any help
Edit:
So I'm still working with it. Here's another weird thing. If I set the index in the KeyList class to timeSlices-1 (basically getting the last Graph in graphs array), and I hit left, it works! But, now the right doesn't! Something weird has to be going on with the array or something because the index changes just fine. Hmm.
Edit:
Something's going on with the array. For some reason, the Graph can only be used once. Perhaps it's being destroyed on removal? Or something like that...

Instead of trying to remove/add panels to a container use a CardLayout which was designed for this purpose.
Also, don't use KeyListeners. Instead you should be using Key Bindings. Then you simply bind the next/previous keys to the next/previous methods of the card layout.

java swing repaint()

(second question in a few hours)
Kay so I'm making a chess variant in java, I have my console program working how I want it but now I'm trying to convert it to a swing GUI while STILL keeping the console things intact. So up to now I have my array of squares with pieces in them for the console, and a 2-dimensional array of JPanels with pieces in them for the GUI. I haven't implemented moving pieces in the GUI yet so I'm still doing it from the console but the actual GUI doesn't update after I've moved a piece...even though it does on the console (sorry if this is confusing).
The GUI consists of a constructor which calls some methods drawBoard() and drawSidebar() and sets sizes, titles etcetc...so this is what the main method looks like:
public static void main(String args[]) {
ChessGUI GUI = new ChessGUI();
Board console = new Board();
do {
console.printBoard();
console.getScore();
console.getMove();
GUI.boardPanel.revalidate();
GUI.sidePanel.revalidate();
GUI.repaint();
} while (true);
}
and drawBoard() incase it makes any difference:
public void drawBoard() {
LayoutManager layout = new GridLayout(NUMBER_OF_ROWS, NUMBER_OF_COLS);
boardPanel.setLayout(layout);
boardPanel.setPreferredSize(new Dimension(200, 450));
chessBoard = new JPanel[NUMBER_OF_ROWS][NUMBER_OF_COLS];
for (int i = 0; i < NUMBER_OF_ROWS; i++) {
for (int j = 0; j < NUMBER_OF_COLS; j++) {
chessBoard[i][j] = new JPanel();
chessBoard[i][j].setBackground(getColor(i,j));
int index = i * 4 + j;
if (!(boardArray.chessBoard[index].square.isEmpty())) {
Piece piece = (Piece) boardArray.chessBoard[index].square.firstElement();
chessBoard[i][j].add(new JLabel(piece.toString()));
}
boardPanel.add(chessBoard[i][j]);
}
}
}
the repaint and revalidate methods don't seem to be calling at all, even though the console is being updated :(

I don't really understand what you are doing. But it doesn't make sense to recreate the entire board panel every time a move is made. All Swing components can only have a single parent, to the easier solution is to just move the piece from one panel to the other. So the code would be something like:
previousPanel.remove( piece );
currentPanel.add( piece );
previousPanel.revalidate();
previousPanel.repaint();
currentPanel.revalidate();

It looks like you're never actually removing anything from 'boardPanel,' even though you are resetting its LayoutManager.
A safer approach might be to remove 'boardPanel' from its container, then create a new instance for 'boardPanel,' add that to the container, then add the other JPanel pieces to this new 'boardPanel.' Effectively, you would be reconstructing the entire JPanel hierarchy after every move.
As you've noticed, Swing can be quite finicky once you start trying to add/move/remove components after they've been added to containers. For games, often the best approach would be to have 1 JComponent/Component and use Java2D methods to draw on top of it. Swing is typically only used for forms-based applications.

Changing the layout doesn't do anything.
You need to call boardPanel.removeChildren()
However, this is going to be extremely slow.
Really, what you should be doing is have your own JPanel, overwrite paintComponent() and draw the images into the appropriate dimensions using Java Graphics.