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Overview
The following two sections explain how you can integrate your .slint designs into your
C++ application. The entry point is a .slint file that contains your primary component
that you instantiate from C++.
There are two ways in that you can instantiate your .slint designs in your C++ application,
either by compiling them ahead of time or by dynamically loading them at run-time.
Once instantiated you feed data into it, for example by setting properties, populating data models or setting up callbacks that are invoked when the user activates certain elements.
Compiled .slint designs
You can choose to compile a .slint file to C++, which provides the best performance
and lowest memory consumption.
The slint_target_sources cmake command makes the translation automatic
and generated code has an API that allows setting and getting
property values, etc. That API will use types from the {ref}slint <namespace_slint>
namespace, for example {cpp:class}slint::SharedString or {cpp:class}slint::Color.
Run-time interpreted .slint designs
Instead of compiling .slint designs to C++, you can also choose to dynamically load .slint
files at run-time. This is slower than compiling them ahead of time and requires more memory,
however it provides more flexibility in your application design.
The entry point to loading a .slint file is the {cpp:class}slint::interpreter::ComponentCompiler
class in the {ref}slint::interpreter <namespace_slint__interpreter> namespace.
With the help of {cpp:class}slint::interpreter::ComponentCompiler you create a {cpp:class}slint::interpreter::ComponentDefinition,
which provides you with information about properties and callbacks that are common to all instances. The
{cpp:func}slint::interpreter::ComponentDefinition::create() function creates new instances, which
are wrapped in {cpp:class}slint::ComponentHandle. This is a smart pointer that owns the actual instance
and keeps it alive as long as at least one {cpp:class}slint::ComponentHandle is in scope, similar to std::shared_ptr<T>.
All property values in .slint are mapped to {cpp:class}slint::interpreter::Value in C++. This is a
polymorphic data type that can hold different kinds of values, such as numbers, strings or even data models.
For more complex UIs it is common to supply data in the form of an abstract data model, that is used with
for - in repetitions or ListView elements in the .slint language.
All models in C++ with the interpreter API are sub-classes of the {cpp:class}slint::Model where the template
parameter is {cpp:class}slint::interpreter::Value. Therefore to provide your own data model, you can subclass
slint::Model<slint::interpreter::Value>.
In .slint files it is possible to declare singletons that are globally available.
You can access them from to your C++ code by exporting them and using the getter and setter functions on
{cpp:class}slint::interpreter::ComponentInstance to change properties and callbacks:
- {cpp:func}
slint::interpreter::ComponentInstance::set_global_property() - {cpp:func}
slint::interpreter::ComponentInstance::get_global_property() - {cpp:func}
slint::interpreter::ComponentInstance::set_global_callback() - {cpp:func}
slint::interpreter::ComponentInstance::invoke_global_callback()