Java Tutorial/SWT/Tree

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Add checkbox mark to the tree node

   <source lang="java">

import org.eclipse.swt.SWT; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Event; import org.eclipse.swt.widgets.Listener; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Tree; import org.eclipse.swt.widgets.TreeItem; public class TreeNodeCheckBoxAdd { 

 public static void main(String[] args) {
   Display display = new Display();
   Shell shell = new Shell(display);
   Tree tree = new Tree(shell, SWT.CHECK | SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL);
   for (int i = 0; i < 12; i++) {
     TreeItem item = new TreeItem(tree, SWT.NONE);
     item.setText("Item " + i);
     for(int l = 0;l<12;l++){
       TreeItem litem = new TreeItem(item, SWT.NONE);
       litem.setText("Item " + i);
     }
     
   }
   tree.setSize(100, 100);
   shell.setSize(200, 200);
   shell.open();
   while (!shell.isDisposed()) {
     if (!display.readAndDispatch())
       display.sleep();
   }
   display.dispose();
 }

}</source>





A multiselection tree

   <source lang="java">

import org.eclipse.swt.SWT; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Tree; import org.eclipse.swt.widgets.TreeItem; /** 

* Displays a single-selection tree, a multiselection tree, and a checkbox tree
*/

public class TreeMultiSelection { 


 public static void main(String[] args) {
   Display display = new Display();
   Shell shell = new Shell(display);
   shell.setText("TreeExample");
   Tree tree = new Tree(shell, SWT.MULTI | SWT.BORDER);
   // Turn off drawing to avoid flicker
   tree.setRedraw(false);
   for (int i = 0; i < 5; i++) {
     TreeItem item = new TreeItem(tree, SWT.NONE);
     item.setText("Root Item " + i);
     for (int j = 0; j < 3; j++) {
       TreeItem child = new TreeItem(item, SWT.NONE);
       child.setText("Child Item " + i + " - " + j);
       for (int k = 0; k < 3; k++) {
         TreeItem grandChild = new TreeItem(child, SWT.NONE);
         grandChild.setText("Grandchild Item " + i + " - " + j + " - " + k);
       }
     }
   }
   tree.setRedraw(true);
     
   tree.setBounds(10,10,400,400);
   shell.open();
   while (!shell.isDisposed()) {
     if (!display.readAndDispatch()) {
       display.sleep();
     }
   }
   display.dispose();
 }

}</source>





A single-selection tree

   <source lang="java">

import org.eclipse.swt.SWT; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Tree; import org.eclipse.swt.widgets.TreeItem; public class TreeSingleSelection { 

 public static void main(String[] args) {
   Display display = new Display();
   Shell shell = new Shell(display);
   shell.setText("TreeExample");
   Tree tree = new Tree(shell, SWT.SINGLE | SWT.BORDER);
   // Turn off drawing to avoid flicker
   tree.setRedraw(false);
   for (int i = 0; i < 5; i++) {
     TreeItem item = new TreeItem(tree, SWT.NONE);
     item.setText("Root Item " + i);
     for (int j = 0; j < 3; j++) {
       TreeItem child = new TreeItem(item, SWT.NONE);
       child.setText("Child Item " + i + " - " + j);
       for (int k = 0; k < 3; k++) {
         TreeItem grandChild = new TreeItem(child, SWT.NONE);
         grandChild.setText("Grandchild Item " + i + " - " + j + " - " + k);
       }
     }
   }
   tree.setRedraw(true);
     
   tree.setBounds(10,10,400,400);
   shell.open();
   while (!shell.isDisposed()) {
     if (!display.readAndDispatch()) {
       display.sleep();
     }
   }
   display.dispose();
 }

}</source>





Create a Tree

   <source lang="java">

import org.eclipse.swt.SWT; import org.eclipse.swt.layout.FillLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Tree; import org.eclipse.swt.widgets.TreeItem; public class TreeCreate { 

 public static void main(String[] args) {
   Display display = new Display();
   Shell shell = new Shell(display);
   shell.setLayout(new FillLayout());
   final Tree tree = new Tree(shell, SWT.BORDER);
   for (int i = 0; i < 4; i++) {
     TreeItem iItem = new TreeItem(tree, 0);
     iItem.setText("TreeItem (0) -" + i);
     for (int j = 0; j < 4; j++) {
       TreeItem jItem = new TreeItem(iItem, 0);
       jItem.setText("TreeItem (1) -" + j);
       for (int k = 0; k < 4; k++) {
         TreeItem kItem = new TreeItem(jItem, 0);
         kItem.setText("TreeItem (2) -" + k);
         for (int l = 0; l < 4; l++) {
           TreeItem lItem = new TreeItem(kItem, 0);
           lItem.setText("TreeItem (3) -" + l);
           for (int m = 0; m < 4; m++) {
             TreeItem mItem = new TreeItem(lItem, 0);
             mItem.setText("TreeItem (3) -" + l);
           }
           
         }
       }
     }
   }
   shell.setSize(200, 200);
   shell.open();
   while (!shell.isDisposed()) {
     if (!display.readAndDispatch())
       display.sleep();
   }
   display.dispose();
 }

}</source>





Create Three Level Tree

   <source lang="java">

import org.eclipse.swt.SWT; import org.eclipse.swt.layout.FillLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Tree; import org.eclipse.swt.widgets.TreeItem; public class TreeThreeLevel { 

 public static void main(String[] args) {
   final Display display = new Display();
   final Shell shell = new Shell(display);
   shell.setLayout(new FillLayout());
   
   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);
       for (int k = 0; k < 3; k++) {
         TreeItem subsubItem = new TreeItem(subItem, SWT.NONE);
         subsubItem.setText("item " + i + " " + j + " " + k);
       }
     }
   }
   shell.setSize(400, 400);
   shell.open();
   while (!shell.isDisposed()) {
     if (!display.readAndDispatch())
       display.sleep();
   }
   display.dispose();
 }

}</source>





Insert TreeItem to Tree

   <source lang="java">

import org.eclipse.swt.SWT; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Tree; import org.eclipse.swt.widgets.TreeItem; public class TreeItemInsert { 

 public static void main(String[] args) {
   Display display = new Display();
   Shell shell = new Shell(display);
   Tree tree = new Tree(shell, SWT.BORDER | SWT.MULTI);
   tree.setSize(200, 200);
   for (int i = 0; i < 5; i++) {
     TreeItem item = new TreeItem(tree, SWT.NONE);
     item.setText("Item " + i);
   }
   
   TreeItem item = new TreeItem(tree, SWT.NONE, 1);
   item.setText("*** New Item ***");
   
   shell.pack();
   shell.open();
   while (!shell.isDisposed()) {
     if (!display.readAndDispatch())
       display.sleep();
   }
   display.dispose();
 }

}</source>





Populate tree lazily

   <source lang="java">

/******************************************************************************* 

* Copyright (c) 2000, 2005 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
*     IBM Corporation - initial API and implementation
*******************************************************************************/

//package org.eclipse.swt.snippets; /* 

* Virtual Tree example snippet: populate tree lazily
*
* For a list of all SWT example snippets see
* http://www.eclipse.org/swt/snippets/
* 
* @since 3.2
*/

import org.eclipse.swt.SWT; import org.eclipse.swt.layout.FillLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Event; import org.eclipse.swt.widgets.Listener; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Tree; import org.eclipse.swt.widgets.TreeItem; public class TreePopulateLazy { 

 public static void main(String[] args) {
   Display display = new Display();
   final Shell shell = new Shell(display);
   shell.setLayout(new FillLayout());
   final Tree tree = new Tree(shell, SWT.VIRTUAL | SWT.BORDER);
   tree.addListener(SWT.SetData, new Listener() {
     public void handleEvent(Event event) {
       TreeItem item = (TreeItem) event.item;
       TreeItem parentItem = item.getParentItem();
       String text = null;
       if (parentItem == null) {
         text = "node " + tree.indexOf(item);
       } else {
         text = parentItem.getText() + " - " + parentItem.indexOf(item);
       }
       item.setText(text);
       item.setItemCount(10);
     }
   });
   tree.setItemCount(20);
   shell.setSize(400, 300);
   shell.open();
   while (!shell.isDisposed()) {
     if (!display.readAndDispatch())
       display.sleep();
   }
   display.dispose();
 }

}</source>





Trees

SWT uses two classes, Tree and TreeItem, to implement tree controls.

Creating Trees



   <source lang="java">

public Tree(Composite parent, int style)</source>



Trees can allow either a single selection or multiple selections.

Tree Styles

StyleDescriptionSWT.SINGLEAllows only one item in the tree to be selected at a time. This is the default.SWT.MULTIAllows multiple items in the tree to be selected at the same time.SWT.CHECKDisplays a checkbox to the left of each of the root items in the tree.

Источник — «http://jexp.ru/index.php?title=Java_Tutorial/SWT/Tree&oldid=3062»