Re: JTree display update issue with new nodes

qu0ll wrote:
Thanks Dan. Please see my recent reply to Bart about this. You are absolutely spot on.


Hi qu0ll,

(1) Your code does this and a blank node is displayed (no userObject is specified):
DefaultMutableTreeNode childNode = new DefaultMutableTreeNode();

(2) The DefaultTreeCellRenderer does this:
String stringValue = tree.convertValueToText(value, sel,
expanded, leaf, row, hasFocus);
setText(stringValue);

(3) And the JTree's convertValueToText does this:
if(value != null) {
String sValue = value.toString();
if (sValue != null) {
return sValue;
}
}
return "";

(4) And the DefaultMutableTreeNode is the value and has no userObject so null is returned in it's toString like this:
if (userObject == null) {
return null;
} else {
return userObject.toString();
}

Cheers,

Dan Andrews
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Ansir Development Limited http://www.ansir.ca
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.

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