qtdoc/doc/src/qmlapp/codingconventions.qdoc

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/*!
\page qml-codingconventions.html
\title QML Coding Conventions
\brief code style convention

This document contains the QML coding conventions that we follow in our documentation and examples and recommend that others follow.

\section1 QML Object Declarations

Throughout our documentation and examples, \l{QML Object Attributes}{QML object attributes} are always structured in the following order:

\list
\li id
\li property declarations
\li signal declarations
\li JavaScript functions
\li object properties
\li child objects
\li states
\li transitions
\endlist

For better readability, we separate these different parts with an empty line.


For example, a hypothetical \e photo QML object would look like this:

\snippet qmlapp/codingconventions/photo.qml 0


\section1 Grouped Properties

If using multiple properties from a group of properties,
consider using \e {group notation} instead of \e {dot notation} if it
improves readability.

For example, this:

\snippet qmlapp/codingconventions/dotproperties.qml 0

could be written like this:

\snippet qmlapp/codingconventions/dotproperties.qml 1


\section1 Lists

If a list contains only one element, we generally omit the square brackets.

For example, it is very common for a component to only have one state.

In this case, instead of:

\snippet qmlapp/codingconventions/lists.qml 0

we will write this:

\snippet qmlapp/codingconventions/lists.qml 1


\section1 JavaScript Code

If the script is a single expression, we recommend writing it inline:

\snippet qmlapp/codingconventions/javascript.qml 0

If the script is only a couple of lines long, we generally use a block:

\snippet qmlapp/codingconventions/javascript.qml 1

If the script is more than a couple of lines long or can be used by different objects, we recommend creating a function and calling it like this:

\snippet qmlapp/codingconventions/javascript.qml 2

For long scripts, we will put the functions in their own JavaScript file and import it like this:

\snippet qmlapp/codingconventions/javascript-imports.qml 0

*/