Editors: Add at least some short documentation.

Change-Id: I7fc7946405d3cbb1af0cf29a9d328d857eb8304a
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

src/plugins/coreplugin/idocument.cpp

@@ -34,6 +34,22 @@
 #include <QFile>
 #include <QFileInfo>
 
+/*!
+    \class Core::IDocument
+    \brief The IDocument class describes a document that can be saved and reloaded.
+
+    The most common use for implementing an IDocument subclass, is as a document for an IEditor
+    implementation. Multiple editors can work in the same document instance, so the IDocument
+    subclass should hold all data and functions that are independent from the specific
+    IEditor instance, for example the content, highlighting information, the name of the
+    corresponding file, and functions for saving and reloading the file.
+
+    Each IDocument subclass works only with the corresponding IEditor subclasses that it
+    was designed to work with.
+
+    \mainclass
+*/
+
 /*!
     \fn QString Core::IDocument::filePath() const
     Returns the absolute path of the file that this document refers to. May be empty for

src/plugins/coreplugin/textdocument.cpp

@@ -34,12 +34,11 @@
 #include <QTextCodec>
 
 /*!
-    \class Core::TextFile
-    \brief The TextFile class is a base class for text files with encoding
-    helpers.
+    \class Core::TextDocument
+    \brief The TextDocument class is a very general base class for documents that work with text.
 
-    This class stores the format obtained from read operations and uses that when writing
-    out files, thus ensuring that CRLF/encodings are preserved.
+    This class contains helper methods for saving and reading text files with encoding and
+    line ending settings.
 
     \sa Utils::TextFileUtils
 */

src/plugins/texteditor/basetextdocument.cpp

@@ -54,6 +54,14 @@
 
 using namespace Core;
 
+/*!
+    \class TextEditor::BaseTextDocument
+    \brief The BaseTextDocument class is the base class for QTextDocument based documents.
+
+    Subclasses of BaseTextEditor can either use BaseTextDocument as is (and this is the default),
+    or created subclasses of BaseTextDocument if they have special requirements.
+*/
+
 namespace TextEditor {
 class BaseTextDocumentPrivate
 {

src/plugins/texteditor/basetexteditor.cpp

@@ -104,6 +104,14 @@
     \internal
 */
 
+/*!
+    \class TextEditor::BaseTextEditor
+    \brief The BaseTextEditor class is a base class for QPlainTextEdit-based text editors.
+
+    The corresponding document base class is BaseTextDocument, the corresponding widget base class
+    is BaseTextEditorWidget.
+*/
+
 using namespace Core;
 using namespace Utils;
 

src/plugins/texteditor/itexteditor.cpp

@@ -33,6 +33,23 @@
 
 using namespace TextEditor;
 
+/*!
+    \class TextEditor::ITextEditorDocument
+    \brief The ITextEditorDocument class is an abstract base for documents of text editors.
+
+    It is the base class for documents used by implementations of the ITextEditor class,
+    and contains basic functions for retrieving text content and markers (like bookmarks).
+*/
+
+/*!
+    \class TextEditor::ITextEditor
+    \brief The ITextEditor class is an abstract base class for text editors.
+
+    It contains the basic functions for retrieving and setting cursor position and selections,
+    and operations on them, like removing or inserting. It uses implementations of
+    ITextEditorDocument as the underlying document.
+*/
+
 ITextEditorDocument::ITextEditorDocument(QObject *parent)
     : Core::TextDocument(parent)
 {

src/plugins/texteditor/plaintexteditor.cpp

@@ -48,6 +48,16 @@
 using namespace Core;
 using namespace TextEditor::Internal;
 
+/*!
+    \class TextEditor::PlainTextEditor
+    \brief The PlainTextEditor class is a text editor implementation that adds highlighting
+    by using the Kate text highlighting definitions, and some basic auto indentation.
+
+    It is the default editor for text files used by \QC, if no other editor implementation
+    matches the MIME type. The corresponding document is implemented in PlainTextDocument,
+    the corresponding widget is implemented in PlainTextEditorWidget.
+*/
+
 namespace TextEditor {
 
 PlainTextEditor::PlainTextEditor(PlainTextEditorWidget *editor)