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Thread: Why is object reference showing in JTable when editing cell?

  1. #1
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    Default Why is object reference showing in JTable when editing cell?

    I'm using a custom CellRenderer, see code below. I have a feeling something I'm doing in this is causing the problem. The CellRenderer itself seems to work fine showing the actual value, but when I edit the cell, I see an object reference instead of the actual value.

    Here's the code:

    public class PlannerCellRenderer extends JLabel implements TableCellRenderer, Serializable {
    	private static final long serialVersionUID = 1L;
    	private Border unselectedBorder = null;
    	private Border selectedBorder = null;
    	boolean isBordered = true;
     
    	public PlannerCellRenderer(boolean isBordered) {
    		super();
    		this.isBordered = isBordered;
    		setOpaque(true);  // MUST do this for background to show up.
    	}
     
    	public Component getTableCellRendererComponent(JTable table, Object cell, boolean isSelected, boolean hasFocus, int row, int column) {
    		Color newColor;
    		if(cell == null) {
    			super.setText("");
    			if (isSelected) {
    				super.setBackground(new Color(50,50,100));
    	        } else {
    	    		super.setBackground(new Color(255,255,255));
    	        }
    			return this;
    		}
    		if(column == 0 ) {
    			super.setText((String)cell);
    			super.setBackground(new Color(255,255,255));
    			super.setForeground(new Color(0,0,0));
    			super.setHorizontalAlignment(JLabel.LEFT);
    			return this;
    		}
    		switch(((DisplayCell)cell).getCellType()) {
    			case DisplayCell.BLANK:
    				newColor = new Color(255,255,255);  // White
    				break;
    			case DisplayCell.FIRSTTYPE:
    				newColor = new Color(128,128,128);	// Grey
    				break;
    			case DisplayCell.SECONDTYPE:
    				newColor = new Color(0,255,0);		// Green
    				break;
    			default:
    				newColor = new Color(255,255,255);	// White
    				break;
    		}
     
    		if(((DisplayCell)cell).getNumberResources() == 0) {
    			super.setText("");
    		} else {
    			super.setText(Integer.toString(((DisplayCell)cell).getNumberResources()));
    		}
     
    		super.setHorizontalAlignment(JLabel.CENTER);
    		if (isSelected) {
    			super.setBackground(new Color(50, 50, 100));
            } else {
        		super.setBackground(newColor);
            }
     
            setToolTipText(DisplayCell.CELLTYPE[((DisplayCell)cell).getCellType()]);
            return this;
    	}
     
    }


  2. #2
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    Default Re: Why is object reference showing in JTable when editing cell?

    Could you elaborate what you mean?

    Do you experience output similar to java.lang.Object@1ba34f2?
    Please use [highlight=Java]//code goes here...[/highlight] tags when posting your code

  3. #3
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    Default Re: Why is object reference showing in JTable when editing cell?

    Exactly. But, I only see something similar to "java.lang.Object@1ba34f2" when I click on the cell to edit it. It displays fine otherwise.

  4. #4
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    Default Re: Why is object reference showing in JTable when editing cell?

    OK, I found my own problem.

    The toString() method is called on the object the CellRenderer is displaying. In my case, DisplayCell. I failed to override the toString() method for this, so the default was returning the reference string name.

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