Package org.eclipse.swt.custom

Class TreeEditor

  • public class TreeEditor
extends ControlEditor
    A TreeEditor is a manager for a Control that appears above a cell in a Tree and tracks with the moving and resizing of that cell. It can be used to display a text widget above a cell in a Tree so that the user can edit the contents of that cell. It can also be used to display a button that can launch a dialog for modifying the contents of the associated cell.

    Here is an example of using a TreeEditor: 

            final Tree tree = new Tree(shell, SWT.BORDER);
        for (int i = 0; i < 3; i++) {
                TreeItem item = new TreeItem(tree, SWT.NONE);
                item.setText("item " + i);
                for (int j = 0; j < 3; j++) {
                        TreeItem subItem = new TreeItem(item, SWT.NONE);
                        subItem.setText("item " + i + " " + j);
                }
        }

        final TreeEditor editor = new TreeEditor(tree);
        //The editor must have the same size as the cell and must
        //not be any smaller than 50 pixels.
        editor.horizontalAlignment = SWT.LEFT;
        editor.grabHorizontal = true;
        editor.minimumWidth = 50;

        tree.addSelectionListener(new SelectionAdapter() {
                public void widgetSelected(SelectionEvent e) {
                        // Clean up any previous editor control
                        Control oldEditor = editor.getEditor();
                        if (oldEditor != null) oldEditor.dispose();

                        // Identify the selected row
                        TreeItem item = (TreeItem)e.item;
                        if (item == null) return;

                        // The control that will be the editor must be a child of the Tree
                        Text newEditor = new Text(tree, SWT.NONE);
                        newEditor.setText(item.getText());
                        newEditor.addModifyListener(new ModifyListener() {
                                public void modifyText(ModifyEvent e) {
                                        Text text = (Text)editor.getEditor();
                                        editor.getItem().setText(text.getText());
                                }
                        });
                        newEditor.selectAll();
                        newEditor.setFocus();
                        editor.setEditor(newEditor, item);
                }
        });
    Since:
    1.0

    • Constructor Summary

      Constructors 
      Constructor Description
      TreeEditor​(Tree tree)
      Creates a TreeEditor for the specified Tree.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void dispose()
      Removes all associations between the TreeEditor and the row in the tree.
      int getColumn()
      Returns the zero based index of the column of the cell being tracked by this editor.
      TreeItem getItem()
      Returns the TreeItem for the row of the cell being tracked by this editor.
      void layout()
      Lays out the control within the underlying composite.
      void setColumn​(int column)
      Sets the zero based index of the column of the cell being tracked by this editor.
      void setEditor​(Control editor)
      Specify the Control that is to be displayed.
      void setEditor​(Control editor, TreeItem item)
      Specify the Control that is to be displayed and the cell in the tree that it is to be positioned above.
      void setEditor​(Control editor, TreeItem item, int column)
      Specify the Control that is to be displayed and the cell in the tree that it is to be positioned above.
      void setItem​(TreeItem item)  

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • TreeEditor

        public TreeEditor​(Tree tree)
        Creates a TreeEditor for the specified Tree.
        Parameters:
        tree - the Tree Control above which this editor will be displayed

    • Method Detail

      • dispose

        public void dispose()
        Removes all associations between the TreeEditor and the row in the tree. The tree and the editor Control are not disposed.
        Overrides:
        dispose in class ControlEditor

      • getColumn

        public int getColumn()
        Returns the zero based index of the column of the cell being tracked by this editor.
        Returns:
        the zero based index of the column of the cell being tracked by this editor

      • getItem

        public TreeItem getItem()
        Returns the TreeItem for the row of the cell being tracked by this editor.
        Returns:
        the TreeItem for the row of the cell being tracked by this editor

      • setColumn

        public void setColumn​(int column)
        Sets the zero based index of the column of the cell being tracked by this editor.
        Parameters:
        column - the zero based index of the column of the cell being tracked by this editor

      • setItem

        public void setItem​(TreeItem item)

      • setEditor

        public void setEditor​(Control editor,
                      TreeItem item,
                      int column)
        Specify the Control that is to be displayed and the cell in the tree that it is to be positioned above.

        Note: The Control provided as the editor must be created with its parent being the Tree control specified in the TreeEditor constructor.

        Parameters:
        editor - the Control that is displayed above the cell being edited
        item - the TreeItem for the row of the cell being tracked by this editor
        column - the zero based index of the column of the cell being tracked by this editor

      • setEditor

        public void setEditor​(Control editor)
        Description copied from class: ControlEditor
        Specify the Control that is to be displayed.

        Note: The Control provided as the editor must be created with its parent being the Composite specified in the ControlEditor constructor.

        Overrides:
        setEditor in class ControlEditor
        Parameters:
        editor - the Control that is displayed above the composite being edited

      • setEditor

        public void setEditor​(Control editor,
                      TreeItem item)
        Specify the Control that is to be displayed and the cell in the tree that it is to be positioned above.

        Note: The Control provided as the editor must be created with its parent being the Tree control specified in the TreeEditor constructor.

        Parameters:
        editor - the Control that is displayed above the cell being edited
        item - the TreeItem for the row of the cell being tracked by this editor

      • layout

        public void layout()
        Description copied from class: ControlEditor
        Lays out the control within the underlying composite. This method should be called after changing one or more fields to force the Editor to resize.
        Overrides:
        layout in class ControlEditor