Use a Link button to make it easy to navigate among pages in a multiple-page document, to open a web site related to the topic of your sketch, or to open a local Sketchpad or Help system document.

Use File | Document Options to add multiple pages to your document.

Choose Edit | Action Buttons | Link to create a Link button.

Choose Edit | Properties | Link to open the Properties panel and set the destination page or URL for the button.

Use URLs to connect your sketch to related mathematical, historic, or reference material available on the Internet. Use special codes in the URL to link to local Sketchpad documents, Help system documents, or other local documents.

This Properties panel appears only for Link action buttons. Use it to determine the destination of the Link button.

The panel appears automatically when you choose Edit | Action Buttons | Link to create a button. After you’ve created the button, choose Edit | Properties, or choose Properties from the Context menu, to display the panel again to make further adjustments.

Use the Link to radio buttons to choose whether the button links to another page in your document or to an Internet URL such as a web page.

Page: When this is chosen, the Link button will link to a different page of the current document. Use the Page pop-up menu to decide which page to link to. If that page contains any action buttons of its own (such as an Animation or Movement button), you can choose one of those buttons in the Button on page pop-up menu to cause the Link button to automatically activate the specified button on the linked page.

Use the File | Document Options command to add or copy new pages into your document.

URL: When this is chosen, the Link button will link to a URL using your web browser. You must enter the actual URL, which can be a web site (if the URL starts with “http://”) or a local file or program (if the URL starts with “file://”).

The default URL points to the Sketchpad Resource Center, a web site with additional resources and information about using Sketchpad. You can copy web page URLs from your browser and paste them here.

URL links can also use these special URL forms:

sketchdoc://: Start the URL with “sketchdoc://” to link to a document in the same folder as the current document. For example, if you want to link from a document named Demo1.gsp to a document called Demo2.gsp in the same folder, you could use the URL “sketchdoc://Demo2.gsp”.

sketchapp://: Start the URL with “sketchapp://” to link to a document in the same folder as the Sketchpad application.

help://: Start the URL with “help://” to link to a document in the Sketchpad Help folder.

file://: Start the URL with “file://” to link to a local document by its path name. Add a third slash ("file:///") to use the absolute path name, starting from the root directory of the current drive.

rdb://: Start the URL with “rdb://” to link to an rdb description of a remote collection of Sketchpad documents on the web. This method allows you to download and open any of the remote documents directly within Sketchpad.

rdl://: Start the URL with “rdl://” to link to a remote Sketchpad document on the web. This allows you to open a remote document directly within Sketchpad.

Internet URLs such as http:// web sites are only accessible if you’re connected to the Internet and have a web browser installed on your computer. Local file:// URLs are useful for accessing documents or other resources on your specific computer, but these buttons may not function if you open your document on another computer (which may well be missing the linked-to documents). The relative URLs — sketchdoc://, sketchapp://, and help:// — let you refer to resources in relation to “known locations” on any computer running Sketchpad. They can be handy if you’re creating a folder of linked documents you’d like to share with others. As long as you use sketchdoc:// URLs, the documents within that folder will stay linked together no matter where you move or copy that folder.