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| <title>Help Placeholders</title> |
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| |
| <h2>Help Placeholders</h2> |
| |
| <p> |
| A help placeholder is used when documentation is not installed at the same time as the corresponding software bundles. |
| A placeholder contains a reference to a help page which describes how to install help bundles. |
| </p> |
| <p> |
| As an example suppose that for reasons of size the documentation bundle org.eclipse.myfeature.doc |
| was a separate download from org.eclipse.myfeature. Users who installed only org.eclipse.myfeature |
| without the documentation would not see the help content for myfeature and a help search would not search org.eclipse.myfeature.doc. If the developers of myfeature add a toc placeholder |
| the user will be made aware that documentation is available and be able to get instructions for installing it. |
| </p> |
| <p> |
| A help placeholder is defined using the placeholder element of the extension point org.eclipse.help.toc. |
| The easiest way to manage placeholders is to create bundles |
| which contain one or more help placeholder extensions and no code. |
| The code bundles will have a dependency to these help placeholder bundles. |
| </p> |
| <p> |
| As an example here is how to setup a placeholder for the ( nonexistent ) help bundle org.eclipse.myfeature.doc |
| A bundle org.eclipse.myfeature.doc.placeholder is created which contains the extension point below and no code.</p> |
| <pre> |
| <extension |
| point="org.eclipse.help.toc"*gt; |
| <placeholder |
| placeholderPage="http://www.eclipse.org/installingmyfeaturedocs.html" |
| plugin="org.eclipse.myfeature.doc"*gt; |
| </placeholder*gt; |
| </extension*gt; |
| </pre> |
| <p> |
| A dependency is added from the Java bundle org.eclipse.myfeature to org.eclipse.myfeature.doc.placeholder. |
| If the help system is launched with org.eclipse.myfeature installed and org.eclipse.myfeature.doc not installed the |
| home page will be replaced with a page informing of the missing documentation bundle. |
| In this example clicking on the link "org.eclipse.myfeature.doc" will open the page http://www.eclipse.org/installingmyfeaturedocs.html. |
| </p> |
| <p> |
| <img src = "images/helpplaceholder.png" alt="help showing placeholder page"> |
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