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Adding images (or any other resources) to Eclipse cheat sheets

>> 13 April 2011

Sometimes it's useful to use images inside cheat sheets. There is one problem, the editor does not allow including images, or any other resources. This tutor describes how to do such things.

This is an excerpt of my little ebook Steps 2 Eclipse Plug-in. This book describes, how my  plug-in for Eclipse: XML Parsing in Java Kit, was written.

If you are interested in this ebook, and/or you want to help the author, please think to buy it.

Adding images or other resources is done using an ItemExtension, this will use a class that handles drawing the images, for instance. The class must implements : org.eclipse.ui.cheatsheets.AbstractItemExtensionElement. This class is associated with an attribute that can be used with an item in your cheat sheet

Adding an extension
Extension tab -> Click on Add button

Select org.eclipse.ui.cheatsheets.cheatSheetItemExtension from the list.

This will add an extension-point

Right click on the newly created extension-point -> New -> ItemExtension

1. Give a name of your choice to the attribute ItemAttribut (this attribute will be used within  an Item tag, in a cheat sheet later)

2. Give a name (preferably full qualified name) to the class that will handle this attribute

3. Click on class link will open a New Java Class dialog for creating the class

The New Java Class dialog is opened
The class's name and its super class are entered automatically by Eclipse
Click on Finish

This class in one of its method createControl(Composite) we add a control  (for instance a label with an image, to its Composite argument, like the following:

    //create a Label
    Label msg=new Label(composite, SWT.BORDER);
    msg.setText("This is a label");

Must have a constructor with a String (done automatically by eclipse)

public class ItemExtensionHandler extends AbstractItemExtensionElement {
private String attributeValue;
    public ItemExtensionHandler(String attributeName) {

    public void handleAttribute(String attributeValue) {


    public void createControl(Composite composite) {

        //get the image from ImageRegistry    
        AbstractUIPlugin plugin=Activator.getDefault();
        ImageRegistry reg=plugin.getImageRegistry();
        Image logo=reg.get(Activator.LOGO_ID);
          //add a label to composite
          Label label=new Label(composite,SWT.BORDER);
         //Use the label to display the image


    public void dispose() {
        // TODO Auto-generated method stub


When the extension was added in the plug-in editor, information about this extension was written in this file, with the attribute name and its handler class.

<?xml version="1.0" encoding="UTF-8"?>
<?eclipse version="3.4"?>


Add the attribute to a cheat sheet
The ItemExtension handler class defined above, is associated with an attribute. Its name was entered in ItemAttribute. We are going to use this item's attribute in a cheat sheet. This attribute will be replaced, by whatever we want to display in createControl(Composite) method of the handler class

Let's create a new cheat sheet to hold the image (you can use the image in any other cheat sheet, alongside a text, using this attribute)

Create a new cheat sheet to hold an image
In composite cheat sheet editor -> click on Add Task
Give the task any Name. Click on Path link to open new simple cheat sheet dialog

Give the new file a name in File name, with .xml extension.
This will open the simple cheat sheet editor

Give a name to this cheat sheet
Click on item to change its name in Title

Click on Source tab. This will open an editor with the source of the cheat sheet .xml file

Using the item's attribut

Use after any item's title the ItemAttribute's name entered when defining ItemExtension. You can give this attribute any value. This value can be obtained in the handler class


<?xml version="1.0" encoding="UTF-8"?>
      title="Cheat sheet with logo">
         title="logo" myAtt="value_of_my_attribute">

Give it a try

In MANIFEST.MF editor (click on META-INF/MANIFEST.MF in Package Explorer)
Select Overview tab
Under Testing
Click on Launch an Eclipse application link

A new instance of Eclipse is launched. Click on Workbench

Click on Help menu -> Cheat Sheets

  Enjoy !


Rich Payton,  August 25, 2011 at 4:54 PM  

I would really like to use this method for adding icons to my cheat sheets.

I would like to say, "In the main toolbar, click 'Run'" and then show the run icon.

As a newb I'm having a hard time following this tutorial. Here are my questions:

1. Am I supposed to insert the yellow highlighted text?
2. How do I add images to the image registry?
3. Where do I add extension point tag if we use different file (not called plugin.xml) to register the cheat sheets?
4. How can I add images to cheat sheets I make using the Cheat Sheet Editor?

I'm really excited to use this capability I just have a few hurdles.

okjavafx August 26, 2011 at 11:21 AM  

Here's a very quick answer. I hope you find it useful.

Answer 1, replace the body of createControl(Composite composite) method, of your class ItemExtensionHandler (or any other name) that extends AbstractItemExtensionElement with the one provided in the tutor. Other codes with yellow, are added for you by Eclipse.

Answer 2. I have just added this post

Answer 3. Sorry, I didn't understand well your question, anyway plugin.xml, is the plug-in descriptor and extensions must be defined there

Answer 4. In the editor "Add Step" will add an in the source code, you can then use the attribute defined with the item extension in "ItemAttribute" (see the tutor)

Hoping that i was clear enough


Christophe Méresse November 9, 2011 at 3:14 PM  


Your tutorial helped me a lot. But there is still a problem I would like to solve. In fact the place used to create the label (the composite) should be used only to put small icons buttons (16*16) like the contextual help icon.
A big image in this place is alway visible even if the item (step) is collapsed and eventually screw the item name (you can see it either with a big image, either by making your eclipse cheat sheet view smaller)

In fact the image should be place inside the collapsible step.
I tried to add it to the parent like this:
Label label=new Label(composite.getParent(), SWT.BORDER);

but was not successfull.

Do you know exactly where I should place it?

Thank you
Christophe Meresse

Christophe Méresse November 10, 2011 at 9:12 AM  

Hello again,

I took time to study in details the cheat sheet classes and I think that what I wanted was not possible. In fact the composite parent is not collapsible object. It is visible in org.eclipse.ui.internal.cheatsheets.views.ViewItem.class

The parent object mainItemComposite (an ExpandableComposite) has two children: titleComposite (which is passed to our entry point, the createControl method) and bodyWrapperComposite (the object where I should put the label with the image).

But unfortunately the createControl method is called before the creation of bodyWrapperComposite that is as a result null when I try to access it like this: (Composite)((ExpandableComposite)composite.getParent()).getClient()

So I think there is no solution. It's a pity that the call to createControl is not done at the end of addItem method...

Christophe Méresse

okjavafx November 10, 2011 at 9:26 AM  

Hello Christophe,

Thank you very much for the comment and for your own answer.


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