JPanel - repaint problem

[thesti]

Hi,

i have problem with a JPanel in my JInternalFrame. it's like a maze game. after the game finished, i want to display game's statistic in the same panel i draw the tiles of the maze. but instead of displaying the statistic labels. it display nothing. I have to move the JInternalFrame so that the panel display the statistic.

how could that after the game finish (the player reach the key), the panel display the statistic immediately?

Here is the code determining that the game has ended

                    if(level==3)
{
    //the game is over if level is 3
    JOptionPane.showMessageDialog(null, winnerName+" has completed this Level!");
 
    gameStart = false;
    playArea.repaint();
}
 

and here is the paintComponent routine of the panel

                  public void paintComponent(Graphics g)
        {
            super.paintComponent(g);
 
            if(gameStart)
                gameMap.drawAll(this, g);
            else
            {
                //display game statistic
                if(addedStatistic==false)
                {
                    setLayout(new FlowLayout(FlowLayout.CENTER,50, 8));
 
                    add(new JLabel("    MAZE GAME PROGRAMME    "));
 
                    //statistic for player1
                    if(player1.isHigherScore())
                    {
                        add(new JLabel("Total score for Player 1 = "+player1.getScore()+" - NEW HIGH SCORE ^^"));
 
                        //update user file with new score
                        player1.updateMyScore();
                    }
                    else
                        add(new JLabel("Total score for Player 1 = "+player1.getScore()));
                    //statistik for player2
                    if(player2.isHigherScore())
                    {
                        add(new JLabel("Total score for Player 2 = "+player2.getScore()+" - NEW HIGH SCORE ^^"));
 
                        //update user file with new score
                        player2.updateMyScore();
                    }
                    else
                        add(new JLabel("Total score for Player 2 = "+player2.getScore()));
 
                    //display winner
                    if(player1.getScore() > player2.getScore())
                        add(new JLabel("Congratulations Player 1 : "+player1.getName()+" Win this Game."));
                    else if(player2.getScore() > player1.getScore())
                        add(new JLabel("Congratulations Player 2 : "+player2.getName()+" Win this Game."));
                    else
                        add(new JLabel("Congratulations You both have the same score"));
 
                    addedStatistic = true;
                    repaint();
                }
            }
        }
 

thx

[JosAH]

It's a threading problem: don't set up all those labels etc. in the paintComponent()
method because it runs in the AWT thread itself, i.e. the thread can't paint those
components (yet) because you're keeping it busy with all these labels.

Create a separate little method that does the setup, invoke it from another thread
and call repaint() at the end; AWT will schedule your paintComponent which sees
the components and delegates to their own paintComponent() methods etc.

kind regards,

Jos

[thesti]

thx Jos,

well, i'm new to Java. so i'm kinda confused with what you mean to invoke the addStatistic method from another thread. i've created another method to add the labels then call repaint. but still the same result.

could you explain me a little bit more?

thx

[JosAH]

thx Jos,

well, i'm new to Java. so i'm kinda confused with what you mean to invoke the addStatistic method from another thread. i've created another method to add the labels then call repaint. but still the same result.

could you explain me a little bit more?

thx

Think of the AWT thread as the one and only thread that does the actual painting.
It calls your paintComponent() method when needed. Your paintComponent()
installs new labels and such so it does it in the AWT thread which is still busy
calling you paintComponent() method so it can't draw anything (yet).

You should install those labels etc. somewhere in another thread. The place
where you test if a player has won is a nice place. Install your labels and then
call repaint() which is a hint to the AWT thread that it should start repainting
everything in the near future.

Your paintComponent() method will reduce to almost nothing: either the game
is still not over so it should repaint those tiles; otherwise it doesn't need to do
anything: labels can repaint themselves and your method should just call:
super.paintComponent(g);

kind regards,

Jos

[thesti]

thx Jos,

i did what you told to create another method to setup the labels and call it from another thread. and i add a little workaround, i call the setSize() so that the labels is painted immediately

thx