Document xml.symbols.showReferencedGrammars

Closes #335

Signed-off-by: David Thompson <davthomp@redhat.com>

Author: datho7561

docs/README.md

@@ -10,6 +10,7 @@ As [vscode-xml](https://github.com/redhat-developer/vscode-xml) consumes the [Le
   * [Preferences](Preferences.md#preferences): More info on available [vscode-xml](https://github.com/redhat-developer/vscode-xml) preferences.
   * [Formatting](Formatting.md#formatting): More info on the available formatting preferences.
   * [XML Commands](Commands.md#commands): More info on the available XML vscode commands.
+  * [Symbols](Symbols.md#symbols): More info on the available settings for the document symbols (outline).
   * [Troubleshooting](Troubleshooting.md#troubleshooting): Info on troubleshooting and fixes to issues.
 
 ## Developer Guide

docs/Symbols.md

@@ -0,0 +1,13 @@
+# Symbols
+
+## Show Referenced Grammars
+
+If `xml.symbols.showReferencedGrammars` is enabled, the referenced grammars will be listed in the document outline.
+The following are also listed:
+ * The association method for each grammar
+ * If the grammar is in the cache. Remote grammars are cached by default. Please refer to the [server cache path documentation](Preferences.md#server-cache-path) for more information.
+
+![An XML document that references two grammars. The referenced grammars are listed in the outline](./images/Symbols/ShowReferencedGrammars.png)
+
+This option has no effect if symbols are disabled through `xml.symbols.enabled`.
+The displayed symbols are affected by `xml.symbols.maxItemsComputed`

docs/Validation.md

@@ -18,6 +18,9 @@ You can `validate your XML with a grammar` (XSD, DTD). In order to do so, you mu
  * XML `completion` based on the grammar.
  * XML `hover` based on the grammar in order to show the documentation.
 
+If the `xml.symbols.showReferencedGrammars` setting is enabled, the method used to associate each grammar is listed in the document symbols.
+Please see the [Show Referenced Grammars documentation](Symbols.md#show-referenced-grammars) for more information.
+
 ## Validation with XSD grammar
 
 In the following sections, we would like to validate the XML `foo.xml` file:

docs/images/Symbols/ShowReferencedGrammars.png

@@ -356,7 +356,7 @@
         "xml.symbols.showReferencedGrammars": {
           "type": "boolean",
           "default": true,
-          "markdownDescription": "Show referenced grammars in the Outline. Default is `true`.",
+          "markdownDescription": "Show referenced grammars in the Outline. Default is `true`. Please see [here](command:xml.open.docs?%5B%7B%22page%22%3A%22Symbols%22%2C%22section%22%3A%22show-referenced-grammars%22%7D%5D) for more information.",
           "scope": "window"
         },
         "xml.extension.jars": {