| 1 | // Copyright (C) 2021 The Qt Company Ltd. |
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| 2 | // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only |
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| 3 | |
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| 4 | #include <private/qqmlfinalizer_p.h> |
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| 5 | |
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| 6 | QT_BEGIN_NAMESPACE |
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| 7 | |
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| 8 | QQmlFinalizerHook::~QQmlFinalizerHook() = default; |
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| 9 | |
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| 10 | /*! |
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| 11 | \class QQmlFinalizerHook |
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| 12 | \internal |
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| 13 | |
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| 14 | QQmlFinalizerHook is an internal interface to run code after the current toplevel |
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| 15 | component has been completed. |
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| 16 | At first, this might look like QQmlParserStaus' componentComplete functionality |
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| 17 | by another name - however there is a difference. To understand it, consider the |
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| 18 | following QML file: |
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| 19 | |
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| 20 | \qml |
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| 21 | import QtQuick |
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| 22 | Item { |
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| 23 | id: root |
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| 24 | Rectangle { |
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| 25 | id: rect |
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| 26 | Rectangle { id: innerRect } |
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| 27 | } |
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| 28 | property Item it: Item {id: myItem } |
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| 29 | } |
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| 30 | \endqml |
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| 31 | |
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| 32 | This file will instantiate 4 (sub-)components: One for each of root, rect, innerRect |
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| 33 | and myItem. If the component gets loaded in a synchronous way, each of their |
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| 34 | componentComplete (if existent) would run directly one after another (in a non-specified |
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| 35 | order). |
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| 36 | |
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| 37 | However, in the case of an asynchronous instantiation, e.g. via a loader, we might interrupt |
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| 38 | the (sub-)component construction partway: There can be a delay between the various |
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| 39 | componentComplete calls, and not all sub-components might have been constructed yet. |
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| 40 | QQmlFinalizerHook::componentFinalized is instead called after all asynchronously instantiated |
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| 41 | (sub-)components have been constructed. Notably, all bindings of those components have also |
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| 42 | been set up. |
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| 43 | |
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| 44 | \note While the engine does not use qobject_cast, tooling still relies on the interface |
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| 45 | being marked as such. Thus you should always use the Q_INTERFACES macro in classes deriving |
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| 46 | from QQmlFinalizerHook. |
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| 47 | */ |
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| 48 | |
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| 49 | /*! |
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| 50 | \fn void QQmlFinalizerHook::componentFinalized() |
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| 51 | |
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| 52 | The customization point provided by this interface. See the class description for |
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| 53 | why it is useful and how it compares to componentComplete. |
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| 54 | |
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| 55 | \sa QQmlParserStatus::componentComplete |
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| 56 | |
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| 57 | */ |
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| 58 | |
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| 59 | QT_END_NAMESPACE |
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| 60 | |
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