diff options
Diffstat (limited to '')
| -rw-r--r-- | src/application.rs | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/src/application.rs b/src/application.rs index a4d20e68..98e160ce 100644 --- a/src/application.rs +++ b/src/application.rs @@ -1,4 +1,4 @@ -use crate::{Command, Element, Settings}; +use crate::{Command, Element, Settings, Subscription}; /// An interactive cross-platform application. /// @@ -117,6 +117,20 @@ pub trait Application: Sized { /// [`Command`]: struct.Command.html fn update(&mut self, message: Self::Message) -> Command<Self::Message>; + /// Returns the event [`Subscription`] for the current state of the + /// application. + /// + /// A [`Subscription`] will be kept alive as long as you keep returning it, + /// and the __messages__ produced will be handled by + /// [`update`](#tymethod.update). + /// + /// By default, this method returns an empty [`Subscription`]. + /// + /// [`Subscription`]: struct.Subscription.html + fn subscription(&self) -> Subscription<Self::Message> { + Subscription::none() + } + /// Returns the widgets to display in the [`Application`]. /// /// These widgets can produce __messages__ based on user interaction. @@ -168,6 +182,10 @@ where self.0.update(message) } + fn subscription(&self) -> Subscription<Self::Message> { + self.0.subscription() + } + fn view(&mut self) -> Element<'_, Self::Message> { self.0.view() } |