Well, there are different IDE's out there in the internet and all of them have different features. They provide some unique awesome features whereas even the best of them could be missing some basic stuffs.
Lets get to the point. When you create a Java Application Project in Netbeans, it creates the SourcePackages folder where you are supposed to create your packages and java classes. Now what if you require other stuffs like images, bitmaps, configuration files, xml's etc. you could create a package and put these stuffs there, but I personally don't like it. You could also put your resources in a different part of the disk than your project folder and reference it, but it will only work until the program is in your computer and it won't be packaged in the jar file. Now I researched on this problem and found a solution. It still may not be the best solution but I like it better than I have found yet.
I will point out the steps.
Now you could see that in the method CustomCellRenderer(), the code is trying to load some image files. Until now It could not find it because we have not added it. Create a package called image and put two GIF files in it called cup.GIF and middle.GIF.
Lets get to the point. When you create a Java Application Project in Netbeans, it creates the SourcePackages folder where you are supposed to create your packages and java classes. Now what if you require other stuffs like images, bitmaps, configuration files, xml's etc. you could create a package and put these stuffs there, but I personally don't like it. You could also put your resources in a different part of the disk than your project folder and reference it, but it will only work until the program is in your computer and it won't be packaged in the jar file. Now I researched on this problem and found a solution. It still may not be the best solution but I like it better than I have found yet.
I will point out the steps.
First create a project
Creating a project is easy and so I am not going to bother with the details. The folder structure that the netbeans create is like this.
I have deleted the default package, and created another one called tutorials, as you could see in the above picture.
Now add a Class
Click on the package tutorial, and add a class called TreeTest. Add the below code.
package tutorials;
/**
*
* @author Rajan Prasad Upadhyay
*/
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeCellRenderer;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.TreeNode;
import javax.swing.tree.TreePath;
/**
*
* @author Rajan Prasad Upadhyay
*/
public class TreeTest {
String name = "name";
public static void main(String[] args) {
javax.swing.JFrame topFrame = new JFrame();
javax.swing.JPanel topPanel = new JPanel();
javax.swing.JScrollPane leftScrollPane = new JScrollPane();
javax.swing.JTree leftTree = new JTree();
//for the cell renderer
leftTree.setCellRenderer(new CustomCellRenderer());
topFrame.setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
//layouts
topFrame.setLayout(new BorderLayout());
topPanel.setLayout(new BorderLayout());
// addition of components
// topPanel.setMaximumSize(new Dimension(Integer.MAX_VALUE,Integer.MAX_VALUE));
topPanel.add(leftScrollPane);
leftScrollPane.getViewport().add(leftTree);
addExperimentEvents(leftTree);
topFrame.setSize(600, 500);
topFrame.setContentPane(topPanel);
topFrame.setVisible(true);
}
public static void addExperimentEvents(JTree tree) {
MouseAdapter ma = new MouseAdapter() {
private void myPopupEvent(MouseEvent e) {
final int x = e.getX();
final int y = e.getY();
final JTree tree = (JTree) e.getSource();
TreePath path = tree.getPathForLocation(x, y);
if (path == null) {
return;
}
tree.setSelectionPath(path);
Object obj = (Object) path.getLastPathComponent();
String label = "Add:";// + obj.toString();
JPopupMenu popup = new JPopupMenu("Menu");
JMenu sectionsMenu = new JMenu("Sections");
JMenuItem menuItem1 = new JMenuItem("Item1");
sectionsMenu.add(menuItem1);
JMenuItem menuItem2 = new JMenuItem("Item2");
sectionsMenu.add(menuItem2);
JMenuItem item = new JMenuItem(label);
item.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent ae) {
System.out.println("Editing the tree");
DefaultMutableTreeNode selNode = (DefaultMutableTreeNode) tree
.getLastSelectedPathComponent();
TreeNode root = (TreeNode) tree.getModel().getRoot();
DefaultTreeModel model = (DefaultTreeModel) tree.getModel();//new DefaultTreeModel(root);
if (selNode != null) {
DefaultMutableTreeNode newNode = new DefaultMutableTreeNode("New Node" + (selNode.getChildCount() + 1));
model.insertNodeInto(newNode, selNode, selNode.getChildCount());//
//model.insertNodeInto(newNode, (MutableTreeNode) root, root.getChildCount());
//tree.expandPath(new TreePath(model.getPathToRoot(newNode.getParent())));
TreeNode[] nodes = model.getPathToRoot(newNode);
TreePath path = new TreePath(nodes);
System.out.println(selNode.getChildCount() + ", " + path);
tree.scrollPathToVisible(path);
tree.setSelectionPath(path);
tree.startEditingAtPath(path);
//model.reload((TreeNode) model.getRoot());
} else {
System.out.println("selNode is null");
}
}
});
//addHoverAction(item);//
//item.add(new JMenuItem("page"));
popup.add(item);
JMenuItem delete = new JMenuItem("Delete");
delete.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent ae) {
TreePath path = tree.getPathForLocation(x, y);
final DefaultMutableTreeNode node = (DefaultMutableTreeNode) path.getLastPathComponent();
DefaultMutableTreeNode parentNode = (DefaultMutableTreeNode) node.getParent();
int childNodeIndex = parentNode.getIndex(node);
System.out.println("Index of node deleted, wrt its parent is : " + childNodeIndex);
DefaultTreeModel model = (DefaultTreeModel) tree.getModel();
if (node.getParent() != null) {
model.removeNodeFromParent(node);
}
}
});
popup.add(delete);
popup.add(new JMenuItem("Move: "));
popup.add(sectionsMenu);
popup.show(tree, x, y);
}
public void mousePressed(MouseEvent e) {
if (e.isPopupTrigger()) {
myPopupEvent(e);
}
}
public void mouseReleased(MouseEvent e) {
if (e.isPopupTrigger()) {
myPopupEvent(e);
}
}
};
tree.addMouseListener(ma);
}
// <editor-fold defaultstate="collapsed" desc="hoverAction">
public static void addHoverAction(final JComponent com) {
MouseAdapter adapter = new MouseAdapter() {
public void mouseEntered(java.awt.event.MouseEvent evt) {
System.out.println("mouse Entered: ");
if (true) {
JPopupMenu pop = new JPopupMenu();
pop.add(new JMenuItem("Node"));
pop.show(com.getParent(), com.getWidth(), com.getHeight());
}
}
};
com.addMouseListener(adapter);
}
// </editor-fold>
//static methods
}
class CustomCellRenderer extends DefaultTreeCellRenderer{
Icon cup;
Icon triangle;
Icon page;
public CustomCellRenderer(){
cup = createImageIcon("/image/cup.GIF");
triangle = createImageIcon("/image/middle.GIF");
page = createImageIcon("/image/cup.GIF");
}
public Component getTreeCellRendererComponent(
JTree tree,
Object value,
boolean sel,
boolean expanded,
boolean leaf,
int row,
boolean hasFocus) {
super.getTreeCellRendererComponent(
tree, value, sel,
expanded, leaf, row,
hasFocus);
if(value.toString().equalsIgnoreCase("colors")){
setIcon(cup);
}else if(value.toString().equalsIgnoreCase("sports")){
setIcon(triangle);
}else if (value.toString().equalsIgnoreCase("food")){
setIcon(page);
}
return this;
}
protected static ImageIcon createImageIcon(String path) {
java.net.URL imgURL = TreeTest.class.getResource(path);
// System.out.println(CustomCellRenderer.class.g);
System.out.println("The image uri is : " + imgURL + " " + path);
if (imgURL != null) {
System.out.println("returning new image icon.");
return new ImageIcon(imgURL);
} else {
System.err.println("Couldn't find file: " + path);
return null;
}
}
}
Now you could see that in the method CustomCellRenderer(), the code is trying to load some image files. Until now It could not find it because we have not added it. Create a package called image and put two GIF files in it called cup.GIF and middle.GIF.
Create a resource folder in eclipse
Right click on the project and click Properties. On the section "Source Package Folders" click Add Folder and create a resources folder in the same location as the src folder is located. The resources will be seen along with src in the panel. Now click ok. Go to the projection location in the file explorer and create a physical folder named resources in the path. Also create a folder called image inside the resources folder and put two small GIF files inside it. You could just cut and paste the image file from your src directory to this directory. Now see the netbeans project explorer. The project must be looking like this.
Now run the project. The gif files you have added will appear in the icon of the tree nodes.
Thats all, thanks for watching my tutorial. Keep coding. Enjoy!!!
