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/*!
    \example places
    \title Places (QML)
    \ingroup qtlocation-examples

    \brief The Places example demonstrates how to search for Places and access
           related content.

    \image qml-places.png

    \section1 Overview

    The Places example presents an application window displaying a map.  At the top of the window
    is a search box, which is used to enter a place search query.  To search for a place enter a
    search term into the text box and click the magnifying glass icon.  To search for a place by
    category, click the category icon to display the list of available categories and select the
    desired category.  The place search query will be for places that are near the current location
    shown on the map.

    The search box provides search term suggestions when three or more characters are entered.
    Selecting one of the suggestions will cause a place search to be performed with the selected
    search text.

    Search results are available from the slide out tab on the left.  Clicking on a search result
    will display details about the place.  If a places has rich content (editorials, reviews and
    images), these can be accessed by the buttons on the details page.  To find similar places
    click the "Find similar" button.  If the current Geo service provider supports it, buttons to
    edit and remove a place will also be available.

    The geo service provider can be changed by accessing the "Provider" menu at the bottom of the
    window.  Depending on the features supported by the provider, the "New" menu allows creating
    new Places and Categories.  To create a new place, select "Place" from the "New" menu and fill
    in the fields.  Click "Go!" to save the place.  To create a new category, select "Category"
    from the "New" menu and fill in the fields.  Click "Go!" to save the category.

    The Places example can work with any of the available geo services plugins.  However, some
    plugins may require additional \l {QtLocation::PluginParameter}{plugin parameters} in order to
    function correctly.  \l {QtLocation::PluginParameter}{Plugin parameters} can be passed on the
    command line using the \c {--plugin} argument, which takes the form:

    \code
        --plugin.<parameter name> <parameter value>
    \endcode

    Refer to the documentation for each of the geo services plugins for details on what plugin
    parameters they support.  The Nokia services plugin supplied with Qt requires an \e app_id and
    \e token pair.  See "\l {Qt Location Nokia Plugin}" for details.

    \section1 Displaying Categories

    Before search by category can be performed, the list of available categories needs to be
    retrieved.  This is achieved by creating a \l CategoryModel.

    \snippet places/places.qml CategoryModel model

    The \l CategoryModel type provides a model of the available categories.  It can provide
    either a flat list or a hierarchical tree model.  In this example, we use a hierarchical tree
    model, by setting the \l {CategoryModel::hierarchical}{hierarchical} property to \e true.  The
    \l {CategoryModel::plugin}{plugin} property is set to \e placesPlugin which is the \e identifier of the
    \l Plugin object used for place search throughout the example.

    Next we create a view to display the category model.

    \snippet places/content/places/CategoryView.qml CategoryModel view 1
    \codeline
    \snippet places/content/places/CategoryView.qml CategoryModel view 2
    \codeline
    \snippet places/content/places/CategoryView.qml CategoryModel view 3

    Because a hierarchical model is being used, a \l VisualDataModel is needed to provide
    navigation functionality.  If flat list model was being used the view could use the
    \l CategoryModel directly.

    The view contains a header item that is used as a back button to navigate up the category tree.
    The \e onClicked handler sets the root index of the \l VisualDataModel to the parent of the
    current index.  Categories are displayed by the \e CategoryDelegate, which provides four
    signals.  The \e onArrowClicked handler sets the root index to the current index causing the
    sub categories of the selected category to be displayed.  The \e onClicked handler emits
    the \b categoryClicked() signal with a category parameter indicating which specific category
    has been chosen.  The \e onCrossClicked handler will invoke the
    categories \l {Category::remove()}{remove()} method.  The \e onEditClicked handler invokes the
    \b editClicked() signal of the root item, this is used to notify which particular category
    is to be edited.

    The \e CategoryDelegate displays the category name and emits the \e clicked signal when
    the text is clicked:

    \snippet places/content/places/CategoryDelegate.qml CategoryModel delegate text

    The \e CategoryDelegate also displays icons for editing, removing and displaying child
    categories.  These icons are shown as desired when the \e showSave and \e showRemove
    and \e showChildren properties are set and only then in cases where the function is
    supported.

    \snippet places/content/places/CategoryDelegate.qml CategoryModel delegate icon


    \target Presenting-Search-Suggestions
    \section1 Presenting Search Suggestions

    The \l PlaceSearchSuggestionModel type is used to fetch suggested search terms based on a
    partially entered search term.

    A new suggestion search is triggered whenever the entered search term is changed.

    \snippet places/content/places/SearchBox.qml PlaceSearchSuggestionModel search text changed

    The \e suggestionsEnabled property is used to temporarily disable search suggestions when a
    suggestion is selected (selecting it updates the search term text).  Suggestions are only
    queried if the length of the search term is three or more characters, otherwise the search
    boxes state is reset.

    When the status of the \l PlaceSearchSuggestionModel changes, the state of the search box is
    changed to display the search suggestions.

    \snippet places/content/places/SearchBox.qml PlaceSearchSuggestionModel model

    The main object in the "SuggestionsShown" state is the \l ListView showing the search
    suggestions.

    \snippet places/content/places/SearchBox.qml PlaceSearchSuggestionModel view 1
    \codeline
    \snippet places/content/places/SearchBox.qml PlaceSearchSuggestionModel view 2

    A \l Text object is used as the delegate to display the suggestion text.  Clicking on the
    suggested search term updates the search term and triggers a place search using the search
    suggestion.


    \section1 Searching for Places

    The \l PlaceSearchModel type is used to search for places.

    \snippet places/places.qml PlaceSearchModel model

    First some of the model's properties are set, which will be used to form the search request.
    The \l {PlaceSearchModel::searchArea}{searchArea} property is set to the
    \e searchRegion object which is a \l GeoCircle with a center that is linked to the current
    location displayed on the \l Map.

    Finally, we define two helper functions \b searchForCategory() and \b {searchForText()},
    which set either the \l {PlaceSearchModel::categories}{categories} or
    \l {PlaceSearchModel::searchTerm}{searchTerm} properties and invokes the
    \l {PlaceSearchModel::update()}{update()} method to start the place search.  The search
    results are displayed in a \l ListView.

    \snippet places/content/places/SearchResultView.qml PlaceSearchModel place list

    The delegate used in the \l ListView, \e SearchResultDelegate, is designed to handle multiple
    search result types via a \l Loader object.  For results of type \e PlaceResult the delegate
    is:

    \snippet places/content/places/SearchResultDelegate.qml PlaceSearchModel place delegate

    \section1 Displaying Place Content

    Places can have additional rich content, including editorials, reviews and images.  Rich
    content is accessed via a set of models.  Content models are generally not created directly by
    the application developer, instead models are obtained from the
    \l {Place::editorialModel}{editorialModel}, \l {Place::reviewModel}{reviewModel} and
    \l {Place::imageModel}{imageModel} properties of the \l Place type.

    \snippet places/content/places/PlaceEditorials.qml PlaceEditorialModel view


    \section1 Place and Category Creation

    Some backends may support creation and saving of new places and categories.  Plugin support can
    be checked an run-time with the \l Plugin::supportsPlaces() method.

    To save a new place, first create a new \l Place object, using the
    \l {Qt::createQmlObject()}{Qt.createQmlObject()} method.  Assign the appropriate plugin and
    place properties and invoke the \l {Place::save()}{save()} method.

    \snippet places/content/places/PlaceDialog.qml Place save

    Category creation is similar:

    \snippet places/content/places/CategoryDialog.qml Category save

    Support for place and category removal can be checked at run-time by using the
    \l {Plugin::supportsPlaces} method, passing in a \l {Plugin::supportsPlaces}{Plugin::PlacesFeatures} flag and
    getting back \e true if the feature is supported. For example one would invoke
    \e {supportsPlaces(Plugin.RemovePlaceFeature)} to check if the \e Plugin.RemovePlaceFeature is supported.


    To remove a place, invoke its \l {Place::remove()}{remove()} method.  To remove a category,
    invoke its \l {Category::remove()}{remove()} method.

    \section1 Running the Example
    The example detects which plugins are available and has an option to show them in the via
    the Provider button.
*/
