I want to set for each node in my JTree a different icon, actually I'm loading each node from a data base, with a "while", I set each icon like a root, leaf or parent. Like this:
All my declarations are global:
private ResultSet myResultSet;
protected DefaultTreeModel treeModel;
private DefaultMutableTreeNode rootNode,childNode,parent1,parent2;
And this is the code where I set my nodes:
myResultSet=rtnNodes(); /*Method that returns a RS with my nodes*/
while(myResultSet.next()){
switch(myResultSet.getInt(1)){ /*The first column is the type of node: root, parent, leaf...*/
case 0: treeModel = new DefaultTreeModel((rootNode=new DefaultMutableTreeNode(myResultSet.getString(2)))); break; /*root node*/
case 1: case 4: parent1 = parent2 = makeNode(rootNode); break; /*parent node*/
case 2: makeNode(parent2); break; /*leaf node*/
case 3: parent2 = makeNode(parent1); break; /*sub patern node*/
} /*makeNode is the method where I create the nodes*/
}
The method makeNode is this:
public DefaultMutableTreeNode makeNode(DefaultMutableTreeNode parent){
//The second column in the RS is the name of the node
treeModel.insertNodeInto((childNode=new DefaultMutableTreeNode(myResultSet.getString(2))),parent,parent.getChildCount());
return childNode;
}
After to fill the treemodel with my nodes, I set the model to my JTree:
myJTree.setModel(treeModel);
myJTree.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);
But the problem is. when I try to set the icons. I create a subclass called myTreeRenderer, and I use this:
myJTree.setCellRenderer(new treeRenderer());
But it doesn't set the icons as I want, the subclass is:
private ImageIcon root,parent,leaf;
public myTreeRenderer() {
root=setIcons(2); /*setIcons is a method that I dont publish in this post, that helps me to set the path of the icons*/
parent=setIcons(3);
leaf=setIcons(4);
}
@Override
public Component getTreeCellRendererComponent(JTree tree,Object value,boolean selected,boolean expanded,boolean leaf,int row,boolean hasFocus){
super.getTreeCellRendererComponent(tree,value,selected,expanded,leaf,row,hasFocus);
DefaultMutableTreeNode nodo = (DefaultMutableTreeNode)value;
TreeNode t = nodo.getParent();
if(t!=null){
setIcon(root);
}
return this;
}
How I can set the icon for each node without using his name? The code of the subclass, as is, set all the nodes with the same icon, and each time I selected a node in the jtree, the getTreeCellRendererComponent runs, I don´t want this.
You can change default UI values for icons of JTree
nodes without any custom renderer:
URL resource = logaff.class.getResource(IMAGE);
Icon icon = new ImageIcon(resource);
UIManager.put("Tree.closedIcon", icon);
UIManager.put("Tree.openIcon", icon);
UIManager.put("Tree.leafIcon", icon);
or use something like next:
@Override
public Component getTreeCellRendererComponent(JTree tree,
Object value, boolean selected, boolean expanded,
boolean leaf, int row, boolean hasFocus) {
super.getTreeCellRendererComponent(tree, value, selected,expanded, leaf, row, hasFocus);
DefaultMutableTreeNode nodo = (DefaultMutableTreeNode) value;
if (tree.getModel().getRoot().equals(nodo)) {
setIcon(root);
} else if (nodo.getChildCount() > 0) {
setIcon(parent);
} else {
setIcon(leaf);
}
return this;
}
Also read about rendering mechanism.