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/*!
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@class QtMvvm::Binding
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This class is returned by the bind() function as a handle to a binding. It can be used to check
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if the binding is valid and can remove a binding again.
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@note You don't need to keep the Binding as reference. The binding will stay even if you don't
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hold any references to it. This class serves as a passive watcher over a binding.
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@sa QtMvvm::bind
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*/
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/*!
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@fn QtMvvm::Binding::isValid
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@returns `true` If the binding is valid and active, `false` if invalid or already unbound
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A binding is considered valid is if has successfully been set up and has not been unbound yet.
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A valid binding means view and viewModel are valid can the properties could be found.
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@sa Binding::unbind, bind()
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*/
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/*!
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@fn QtMvvm::bind(QObject*, const char*, QObject*, const char*, Binding::BindingDirection, const char*, const char*)
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@param viewModel The object in the role of a viewmodel
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@param viewModelProperty The property of the viewmodel to use in the binding
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@param view The object in the role of a view
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@param viewProperty The property of the view to use in the binding
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@param type The type/direction of binding to create
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@param viewModelChangeSignal An alternative signal to be used instead of the viewModelProperty
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notify signal to detect property changes
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@param viewChangeSignal An alternative signal to be used instead of the viewProperty notify
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signal to detect property changes
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@returns A handle to the newly created binding, or an invalid handle on errors
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The methods creates a binding similar to the QML bindings, but it is possible to create two-way
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bindings with this method as well. A binding means that whenever a property changes, the property
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it is bound to is updated to the changed value as well.
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@code{.cpp}
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//sample usage
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QtMvvm::bind(this->viewModel, "name", // A viewmodel that has a property named "name"
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ui->nameLabel, "text"); // A view (for example a QLabel) that has a property named "text"
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//any changes to "name" will update "text" and the other way around
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@endcode
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To control the directions, i.e. which properties should trigger an update on changes and which
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only get updated, use the `type` parameter.
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@attention Unlike the QML variant, this binding **does not handle binding loops**. THis means if
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you use a two way binding, make sure change signals are only emitted when the value does actually
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change. Otherwise your application is caught up in a binding loop and will eventually crash. Using
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two seperate one way bindings will not prevent this.
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If the properties you want to use don't have a change signal or you don't want to use that signal,
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you can use the `viewModelChangeSignal` and `viewChangeSignal` to overwrite the signal to be used.
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Please note that you must specify the full signal signature. For example, the signatur of the
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signal `void foo(const QString &bar);` has the signature `foo(QString)`. See QMetaMethod for more
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details. If you leave the parameter out or set it to `nullptr` (or `{}`, an invalid meta method)
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the notify signals of the properties are used.
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@sa Binding
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*/
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