Trait iced_winit::program::Program
source · pub trait Program{
type Message: Debug + Send;
type Theme;
type Executor: Executor;
type Renderer: Renderer + Renderer;
type Flags;
// Required methods
fn new(flags: Self::Flags) -> (Self, Task<Self::Message>);
fn title(&self, window: Id) -> String;
fn update(&mut self, message: Self::Message) -> Task<Self::Message>;
fn view(
&self,
window: Id,
) -> Element<'_, Self::Message, Self::Theme, Self::Renderer>;
fn theme(&self, window: Id) -> Self::Theme;
// Provided methods
fn style(&self, theme: &Self::Theme) -> Appearance { ... }
fn subscription(&self) -> Subscription<Self::Message> { ... }
fn scale_factor(&self, window: Id) -> f64 { ... }
}
program
only.Expand description
An interactive, native, cross-platform, multi-windowed application.
This trait is the main entrypoint of multi-window Iced. Once implemented, you can run
your GUI application by simply calling run
. It will run in
its own window.
A Program
can execute asynchronous actions by returning a
Task
in some of its methods.
When using a Program
with the debug
feature enabled, a debug view
can be toggled by pressing F12
.
Required Associated Types§
sourcetype Executor: Executor
type Executor: Executor
The Executor
that will run commands and subscriptions.
The default executor can be a good starting point!
Required Methods§
sourcefn new(flags: Self::Flags) -> (Self, Task<Self::Message>)
fn new(flags: Self::Flags) -> (Self, Task<Self::Message>)
Initializes the Program
with the flags provided to
run
as part of the Settings
.
Here is where you should return the initial state of your app.
Additionally, you can return a Task
if you need to perform some
async action in the background on startup. This is useful if you want to
load state from a file, perform an initial HTTP request, etc.
sourcefn title(&self, window: Id) -> String
fn title(&self, window: Id) -> String
Returns the current title of the Program
.
This title can be dynamic! The runtime will automatically update the title of your application when necessary.
Provided Methods§
sourcefn style(&self, theme: &Self::Theme) -> Appearance
fn style(&self, theme: &Self::Theme) -> Appearance
Returns the Style
variation of the Theme
.
sourcefn subscription(&self) -> Subscription<Self::Message>
fn subscription(&self) -> Subscription<Self::Message>
Returns the event Subscription
for the current state of the
application.
The messages produced by the Subscription
will be handled by
update
.
A Subscription
will be kept alive as long as you keep returning it!
By default, it returns an empty subscription.
sourcefn scale_factor(&self, window: Id) -> f64
fn scale_factor(&self, window: Id) -> f64
Returns the scale factor of the window of the Program
.
It can be used to dynamically control the size of the UI at runtime (i.e. zooming).
For instance, a scale factor of 2.0
will make widgets twice as big,
while a scale factor of 0.5
will shrink them to half their size.
By default, it returns 1.0
.