XML
IntelliJ IDEA brings powerful support for XML that includes structure validation, formatting (CtrlAlt0L) and indentation (CtrlAlt0I according to the XML code style, importing unbound namespaces, viewing code structure, unwrapping and removing tags (CtrlShiftDelete), generating DTD files and schemas from instance documents, as well as syntax and error highlighting, code completion (CtrlSpace), intention actions (AltEnter), quick documentation look-up (Ctrl0Q), and more.
IntelliJ IDEA uses Xerces 2.11, an XML parser developed by Apache Software Foundation Group.
If you use a tag or an attribute from a namespace that is not bound, IntelliJ IDEA detects the problem and shows a tooltip:
To solve the problem, use the quick-fix that IntelliJ IDEA suggests.
Press AltEnter. If there are multiple choices, select the desired namespace from the list.
Alternatively, hover over the problem and click Create namespace declaration in the popup that opens. If there are multiple choices, select the desired namespace from the list.
Depending on the file type, IntelliJ IDEA creates a namespace declaration, or a taglib.
You can configure XML-aware syntax highlighting according to your preferences and habits.
In the Settings dialog (CtrlAlt0S) , go to Editor | Color Scheme | XML.
Select the color scheme, accept the highlighting settings inherited from the defaults or customize them as described in Colors and fonts.
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