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++ // Copyright (C) 2017 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
++ /*!
++ \example texteditor
++ \keyword Qt Quick Controls - Text Editor
++ \title Qt Quick Controls - Text Editor
++ \keyword Qt Quick Controls 2 - Text Editor
++ \ingroup qtquickcontrols-examples
++ \examplecategory {Graphics}
++ \brief A rich-text editor app using Qt Quick Controls.
++
++ The \e {Text Editor Example} allows WYSIWYG editing of an HTML, Markdown or
++ plain text file. The application comes with two user interfaces: one for
++ larger screens, and a simplified UI for small touch-based devices. Both are
++ "pure" QML. \c texteditor.cpp contains the \c main() function, which calls
++ QFontDatabase::addApplicationFont() to add an icon font. (\l FontLoader
++ would be an alternative way to achieve the same result.)
++
++ \section1 Desktop User Interface
++
++ \image qtquickcontrols-texteditor-desktop.jpg
++ {Text editor with menu bar, toolbar, and formatted document content}
++
++ The desktop version is a complete text editor with capabilities for formatting
++ text, and opening and saving HTML, Markdown and plain text files.
++
++ In the \l {https://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller}{model-view-control (MVC)}
++ design pattern, the \e control layer includes the set of operations that
++ can be performed. In Qt Quick Controls, the \l Action type is used to
++ encapsulate a single operation or command. Accordingly, we begin with a
++ set of Action objects:
++
++ \quotefromfile texteditor/qml/texteditor.qml
++ \skipto Action
++ \printuntil openAction
++ \printto Action
++
++ The \l Action for opening a file must first prompt the user if the existing
++ document has been changed, to avoid losing the user's changes. Otherwise
++ it simply opens the FileDialog which is declared further below.
++
++ The \l Action for saving the file is enabled only if there are changes to save:
++
++ \printuntil saveAction
++ \printto Action
++
++ \skipto quitAction
++ \skipuntil }
++
++ The \l Action for copying selected text is enabled only if some text is selected:
++
++ \printuntil copyAction
++ \printuntil }
++
++ \skipto pasteAction
++ \skipuntil }
++
++ Each Action to change text formatting (such as bold, italic and alignment)
++ is \l {Action::}{checkable}, and its boolean \c checked state
++ is in sync with the relevant property in the
++ \l {TextEdit::selectedText}{selected text}.
++ Since declarative bidirectional synchronization is difficult, we use
++ an \c onTriggered script to change the property when the Action is
++ activated. The \l {TextEdit::}{cursorSelection} property
++ is new in Qt 6.7 and makes this much easier than it was.
++
++ \printuntil boldAction
++ \printto Action
++
++ \skipto alignLeftAction
++ \skipuntil }
++
++ \printuntil alignCenterAction
++ \printto Action
++
++ We have a \l MenuBar containing the hierarchy of \l {Menu}{Menus} and
++ MenuItems. Each \l MenuItem merely needs to bind the relevant
++ \l {AbstractButton::}{action}, which encapsulates the
++ UI representation and the implementation.
++
++ \skipto MenuBar
++ \printuntil copyAction
++ \printuntil }
++ \dots 8
++
++ The same \l Action objects are reused in the \l ToolBar; but here we
++ override each Action's \l {AbstractButton::}{text} property to
++ choose a textual icon from our icon font:
++
++ \skipto ToolBar
++ \printuntil copyButton
++ \printuntil }
++ \dots 12
++
++ The main part of the text editor is a \l TextArea inside a \l Flickable:
++
++ \skipto Flickable
++ \printuntil persistentSelection
++ \dots 12
++
++ A \l ScrollBar is attached to the vertical axis. Since word-wrapping is
++ enabled via \l {TextEdit::}{wrapMode}, we don't need a horizontal
++ ScrollBar.
++
++ The \l {TextArea.flickable} attached property is used
++ so that when the text cursor is moved out of the viewport (for example via
++ arrow keys, or by typing a lot of text), \l TextArea scrolls the
++ \l Flickable to keep the cursor visible.
++
++ We take the same actions that we declared in the \l MenuBar and \l ToolBar
++ and append them to the existing items in the standard
++ \l {ContextMenu}{context menu} provided by \c TextArea:
++
++ \skipto ContextMenu
++ \printto }
++
++ We consistently use the \l [QML] {Qt::}{qsTr()} function to enable
++ translation of UI text, so that the application will make sense regardless
++ of the end user's native language.
++
++ We use several kinds of \l {Qt Quick Dialogs QML Types}{dialogs}:
++
++ \quotefromfile texteditor/qml/texteditor.qml
++ \skipto FileDialog
++ \printuntil discardDialog
++ \printuntil }
++ \printuntil }
++
++ It's generally easier to declare separate instances for each purpose.
++ We have two instances of \l {QtQuick.Dialogs::}{FileDialog}, for opening
++ and saving files respectively. This became easier in Qt 6.7, with new
++ features in \l TextDocument.
++
++ A \l {QtQuick.Dialogs::}{FontDialog} and a \l {QtQuick.Dialogs::ColorDialog}{ColorDialog}
++ allow changing text formatting. (In Markdown format, there's no syntax to
++ represent specific font and color choices; but font characteristics such as
++ bold, italic and monospace are saved. In HTML format, all formatting is
++ saved.)
++
++ We have a \l {QtQuick.Dialogs::}{MessageDialog} to show error messages, and
++ two more for prompting the user what to do when a file has been modified.
++
++ \section1 Touch User Interface
++
++ \image qtquickcontrols-texteditor-touch.jpg
++ {Text editor interface for touch devices with formatting toolbar}
++
++ The touch user interface is a simplified version of the text editor. It is
++ suitable for touch devices with limited screen size. The example uses
++ \l{Using File Selectors with Qt Quick Controls}{file selectors} to load
++ the appropriate user interface automatically.
++
++ \include examples-run.qdocinc
++ */