Start all CheckBoxes of a selected JTree

0

I would like to know how I could do to start the class already with all checkboxes checked, I found this class and I used:

package CustonComponents;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.util.EventListener;
import java.util.EventObject;
import java.util.HashMap;
import java.util.HashSet;

import javax.swing.JCheckBox;
import javax.swing.JPanel;
import javax.swing.JTree;
import javax.swing.event.EventListenerList;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeSelectionModel;
import javax.swing.tree.TreeCellRenderer;
import javax.swing.tree.TreeModel;
import javax.swing.tree.TreeNode;
import javax.swing.tree.TreePath;

public class JCheckBoxTree extends JTree {    

    private static final long serialVersionUID = -4194122328392241790L;

    JCheckBoxTree selfPointer = this;

    // Defining data structure that will enable to fast check-indicate the state of each node
    // It totally replaces the "selection" mechanism of the JTree
    private class CheckedNode {

        boolean isSelected;
        boolean hasChildren;
        boolean allChildrenSelected;

        public CheckedNode(boolean isSelected_, boolean hasChildren_, boolean allChildrenSelected_) {
            isSelected = isSelected_;
            hasChildren = hasChildren_;
            allChildrenSelected = allChildrenSelected_;
        }
    }
    HashMap<TreePath, CheckedNode> nodesCheckingState;
    HashSet<TreePath> checkedPaths = new HashSet<TreePath>();

    // Defining a new event type for the checking mechanism and preparing event-handling mechanism
    protected EventListenerList listenerList = new EventListenerList();

    public class CheckChangeEvent extends EventObject {

        private static final long serialVersionUID = -8100230309044193368L;

        public CheckChangeEvent(Object source) {
            super(source);
        }
    }

    public interface CheckChangeEventListener extends EventListener {

        public void checkStateChanged(CheckChangeEvent event);
    }

    public void addCheckChangeEventListener(CheckChangeEventListener listener) {
        listenerList.add(CheckChangeEventListener.class, listener);
    }

    public void removeCheckChangeEventListener(CheckChangeEventListener listener) {
        listenerList.remove(CheckChangeEventListener.class, listener);
    }

    void fireCheckChangeEvent(CheckChangeEvent evt) {
        Object[] listeners = listenerList.getListenerList();
        for (int i = 0; i < listeners.length; i++) {
            if (listeners[i] == CheckChangeEventListener.class) {
                ((CheckChangeEventListener) listeners[i + 1]).checkStateChanged(evt);
            }
        }
    }

    // Override
    public void setModel(TreeModel newModel) {
        super.setModel(newModel);
        resetCheckingState();
    }

    // New method that returns only the checked paths (totally ignores original "selection" mechanism)
    public TreePath[] getCheckedPaths() {
        return checkedPaths.toArray(new TreePath[checkedPaths.size()]);
    }

    // Returns true in case that the node is selected, has children but not all of them are selected
    public boolean isSelectedPartially(TreePath path) {
        CheckedNode cn = nodesCheckingState.get(path);
        return cn.isSelected && cn.hasChildren && !cn.allChildrenSelected;
    }

    private void resetCheckingState() {
        nodesCheckingState = new HashMap<TreePath, CheckedNode>();
        checkedPaths = new HashSet<TreePath>();
        DefaultMutableTreeNode node = (DefaultMutableTreeNode) getModel().getRoot();
        if (node == null) {
            return;
        }
        addSubtreeToCheckingStateTracking(node);
    }

    // Creating data structure of the current model for the checking mechanism
    private void addSubtreeToCheckingStateTracking(DefaultMutableTreeNode node) {
        TreeNode[] path = node.getPath();
        TreePath tp = new TreePath(path);
        CheckedNode cn = new CheckedNode(false, node.getChildCount() > 0, false);
        nodesCheckingState.put(tp, cn);
        for (int i = 0; i < node.getChildCount(); i++) {
            addSubtreeToCheckingStateTracking((DefaultMutableTreeNode) tp.pathByAddingChild(node.getChildAt(i)).getLastPathComponent());
        }
    }

    // Overriding cell renderer by a class that ignores the original "selection" mechanism
    // It decides how to show the nodes due to the checking-mechanism
    private class CheckBoxCellRenderer extends JPanel implements TreeCellRenderer {

        private static final long serialVersionUID = -7341833835878991719L;
        JCheckBox checkBox;

        public CheckBoxCellRenderer() {
            super();
            this.setLayout(new BorderLayout());
            checkBox = new JCheckBox();
            add(checkBox, BorderLayout.CENTER);
            setOpaque(false);
        }

        @Override
        public Component getTreeCellRendererComponent(JTree tree, Object value,
                boolean selected, boolean expanded, boolean leaf, int row,
                boolean hasFocus) {
            DefaultMutableTreeNode node = (DefaultMutableTreeNode) value;
            Object obj = node.getUserObject();
            TreePath tp = new TreePath(node.getPath());
            CheckedNode cn = nodesCheckingState.get(tp);
            if (cn == null) {
                return this;
            }
            checkBox.setSelected(cn.isSelected);
            checkBox.setText(obj.toString());
            checkBox.setOpaque(cn.isSelected && cn.hasChildren && !cn.allChildrenSelected);
            return this;
        }
    }

    public JCheckBoxTree() {
        super();
        // Disabling toggling by double-click
        this.setToggleClickCount(0);
        // Overriding cell renderer by new one defined above
        CheckBoxCellRenderer cellRenderer = new CheckBoxCellRenderer();
        this.setCellRenderer(cellRenderer);

        // Overriding selection model by an empty one
        DefaultTreeSelectionModel dtsm = new DefaultTreeSelectionModel() {            
            private static final long serialVersionUID = -8190634240451667286L;

            // Totally disabling the selection mechanism
            public void setSelectionPath(TreePath path) {
            }

            public void addSelectionPath(TreePath path) {
            }

            public void removeSelectionPath(TreePath path) {
            }

            public void setSelectionPaths(TreePath[] pPaths) {
            }
        };
        // Calling checking mechanism on mouse click
        this.addMouseListener(new MouseListener() {
            public void mouseClicked(MouseEvent arg0) {
                TreePath tp = selfPointer.getPathForLocation(arg0.getX(), arg0.getY());                
                if (tp == null) {
                    return;
                }
                boolean checkMode = !nodesCheckingState.get(tp).isSelected;
                checkSubTree(tp, checkMode);
                updatePredecessorsWithCheckMode(tp, checkMode);
                // Firing the check change event
                fireCheckChangeEvent(new CheckChangeEvent(new Object()));
                // Repainting tree after the data structures were updated
                selfPointer.repaint();
            }

            public void mouseEntered(MouseEvent arg0) {
            }

            public void mouseExited(MouseEvent arg0) {
            }

            public void mousePressed(MouseEvent arg0) {
            }

            public void mouseReleased(MouseEvent arg0) {
            }
        });
        this.setSelectionModel(dtsm);
    }

    // When a node is checked/unchecked, updating the states of the predecessors
    protected void updatePredecessorsWithCheckMode(TreePath tp, boolean check) {
        TreePath parentPath = tp.getParentPath();
        // If it is the root, stop the recursive calls and return
        if (parentPath == null) {
            return;
        }
        CheckedNode parentCheckedNode = nodesCheckingState.get(parentPath);
        DefaultMutableTreeNode parentNode = (DefaultMutableTreeNode) parentPath.getLastPathComponent();
        parentCheckedNode.allChildrenSelected = true;
        parentCheckedNode.isSelected = false;
        for (int i = 0; i < parentNode.getChildCount(); i++) {
            TreePath childPath = parentPath.pathByAddingChild(parentNode.getChildAt(i));
            CheckedNode childCheckedNode = nodesCheckingState.get(childPath);
            // It is enough that even one subtree is not fully selected
            // to determine that the parent is not fully selected
            if (!childCheckedNode.allChildrenSelected) {
                parentCheckedNode.allChildrenSelected = false;
            }
            // If at least one child is selected, selecting also the parent
            if (childCheckedNode.isSelected) {
                parentCheckedNode.isSelected = true;
            }
        }
        if (parentCheckedNode.isSelected) {
            checkedPaths.add(parentPath);
        } else {
            checkedPaths.remove(parentPath);
        }
        // Go to upper predecessor
        updatePredecessorsWithCheckMode(parentPath, check);
    }

    // Recursively checks/unchecks a subtree
    protected void checkSubTree(TreePath tp, boolean check) {
        CheckedNode cn = nodesCheckingState.get(tp);
        cn.isSelected = check;
        DefaultMutableTreeNode node = (DefaultMutableTreeNode) tp.getLastPathComponent();
        for (int i = 0; i < node.getChildCount(); i++) {
            checkSubTree(tp.pathByAddingChild(node.getChildAt(i)), check);
        }
        cn.allChildrenSelected = check;
        if (check) {
            checkedPaths.add(tp);
        } else {
            checkedPaths.remove(tp);
        }
    }   

}

Test Class

package checkboxtree;

public class NovoJFrame extends javax.swing.JFrame {

    public NovoJFrame() {
        initComponents();
    }

    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jScrollPane1 = new javax.swing.JScrollPane();
        jCheckBoxTree1 = new CustonComponents.JCheckBoxTree();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jScrollPane1.setViewportView(jCheckBoxTree1);

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 152, javax.swing.GroupLayout.PREFERRED_SIZE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 245, javax.swing.GroupLayout.PREFERRED_SIZE)
        );

        pack();
    }// </editor-fold>                        

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(NovoJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(NovoJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(NovoJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(NovoJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new NovoJFrame().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    private CustonComponents.JCheckBoxTree jCheckBoxTree1;
    private javax.swing.JScrollPane jScrollPane1;
    // End of variables declaration                   
}

I would like all classes to be started when I initialize the class !!

    
asked by anonymous 01.07.2016 / 16:21

1 answer

2

The posted code itself has explanations about its use. In class CheckedNode it says the following:

  

Defining data structure that will enable you to quickly check the state of each node.
  It totally replaces the "selection" mechanism of the JTree.

In short, this class is responsible for indicating the status of JCheckBoxes on each Node. Notice that it has the following constructor:

    public CheckedNode(boolean isSelected_, boolean hasChildren_, boolean allChildrenSelected_) {
        isSelected = isSelected_;
        hasChildren = hasChildren_;
        allChildrenSelected = allChildrenSelected_;
    }

It gets 3 parameters:

  • The first one indicates whether the node checkbox is checked (checked);

  • The second indicates whether the node has "children". Note that this check is done with node.getChildCount() > 0 , that is, it checks if the number of internal nodes is greater than zero, if greater, returns true, which indicates that it has subelements.

  • The third indicates whether, if the node has "children" (other nodes or checkboxes), all are selected. This control serves more to highlight the darker background, indicating that not all elements of that node are checked, but there are some that have been.

Understanding how this class works, just change how the addSubtreeToCheckingStateTracking() method is starting the CheckedNode class. This class is called several times because it is the one that mounts the structure of all nodes of JTree .

On line:

CheckedNode cn = new CheckedNode(false, node.getChildCount() > 0, false);

Change to:

CheckedNode cn = new CheckedNode(true, node.getChildCount() > 0, true);

In this way, you are indicating that you want both the node checkbox and the child node to be checked when the screen opens.

    
01.07.2016 / 20:34