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POgetComponentAt() not finding a component?
 

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  1. POgetComponentAt() not finding a component?
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    <p>I am using a <code>JFrame</code> to set up a game of Solitaire, using Cards that extend <code>JLabel</code> so that they can be dragged around the screen. However, one of my requirements is that I be able to double click a card and it snaps up to the 4 stacks of aces. This is not a problem. what is causing problems is that I set this up in an array, so that the aces would go to the spot that corresponds with the suit of the ace, then I have the spots rearrange if a card is dragged up there. If it is double clicked, the aces must go to the first spot (from the left) then the second, and so on. I had planned to use <code>getComponentAt()</code> to find out what was at the first spot and if I could place the ace there, if not then i move on to the second and so on. For some reason though, even if I hard code in the parameters into <code>getComponentAt()</code> to spots I know have a component, it is still returning null.</p> <p>this is the relevant portion of my code: </p> <pre><code>Container contentPane = getContentPane(); contentPane.setLayout(null); ... for(int i = 0; i &lt; 4; i++) { aces[i] = new Card(); aces[i].setBounds((i * 75) + 475, 25, 75, 100); contentPane.add(aces[i]); aces[i].setBorder(BorderFactory.createLineBorder(Color.BLACK, 3)); aces[i].setSuit(i + 1); } System.out.println(contentPane.getComponentAt(475, 25)); </code></pre> <p>This is returning <code>null</code> every time, no matter where in the component i put the coordinates. Any explanations?</p> <p>*Updated SSCCE: This is the main class, solitaire:</p> <pre><code>import java.util.*; import javax.swing.*; import java.awt.*; public class Solitaire extends JFrame { private Container contentPane; private Card aces[]; public static void main(String args[]) { Solitaire frame = new Solitaire(); frame.setVisible(true); } public Solitaire() { super(); contentPane = getContentPane(); contentPane.setLayout(null); contentPane.setBackground(Color.GREEN.darker().darker()); setTitle("Solitaire"); setSize(800,800); setResizable(false); setLocation(250, 50); setDefaultCloseOperation(EXIT_ON_CLOSE); play(); } public void play() { contentPane.removeAll(); aces = new Card[4]; for(int i = 0; i &lt; 4; i++) { aces[i] = new Card(0,i + 1); aces[i].setBounds((i * 75) + 475, 25, 75, 100); contentPane.add(aces[i]); aces[i].setBorder(BorderFactory.createLineBorder(Color.BLACK, 3)); } for(int i = 0; i &lt; contentPane.getComponents().length; i++) System.out.println(contentPane.getComponents()[i]); System.out.println(contentPane.getComponentAt(475, 25)); repaint(); } } </code></pre> <p>and this is Class Card:</p> <pre><code>import javax.swing.*; public class Card extends JLabel { private int numb; private int value; private int suit; public Card(int n, int s) { super(); numb = n; suit = s; } } </code></pre> <p>This ran for me, comment if you need more to solve the problem.</p>
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    1. USHarper
    1. USHarper
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    2. VO
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      1. USSharad Yadav
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    1. COFor better help sooner, post an [SSCCE](http://sscce.org/).
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      1. USAndrew Thompson
    2. COUse `contentpane.getComponentAt(index)`
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      1. USAmarnath
    3. CO@AndrewThompson So do you have that response programmed to a function key? ;)
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      1. USMadProgrammer
 

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