add action set icon while running (#1590)

* set windows icon live action

* change get icon to insto raw

* remove mobile docs

* format

* fix format

* add file methods to Icon

* Rename action to `ChangeIcon` and tidy up `Icon` modules

* Fix documentation of `icon::Error`

* Remove unnecessary `\` in `icon` documentation

* Remove `etc.` from `Icon` documentation

---------

Co-authored-by: Héctor Ramón Jiménez <hector0193@gmail.com>

1 files changed, 20 insertions, 1 deletions

diff --git a/native/src/window/action.rs b/native/src/window/action.rs
index ce36d129..095a8eec 100644
--- a/native/src/window/action.rs
+++ b/native/src/window/action.rs
@@ -1,4 +1,4 @@
-use crate::window::{Mode, UserAttention};
+use crate::window::{Icon, Mode, UserAttention};
 
 use iced_futures::MaybeSend;
 use std::fmt;
@@ -78,6 +78,21 @@ pub enum Action<T> {
     ChangeAlwaysOnTop(bool),
     /// Fetch an identifier unique to the window.
     FetchId(Box<dyn FnOnce(u64) -> T + 'static>),
+    /// Changes the window [`Icon`].
+    ///
+    /// On Windows and X11, this is typically the small icon in the top-left
+    /// corner of the titlebar.
+    ///
+    /// ## Platform-specific
+    ///
+    /// - **Web / Wayland / macOS:** Unsupported.
+    ///
+    /// - **Windows:** Sets `ICON_SMALL`. The base size for a window icon is 16x16, but it's
+    ///   recommended to account for screen scaling and pick a multiple of that, i.e. 32x32.
+    ///
+    /// - **X11:** Has no universal guidelines for icon sizes, so you're at the whims of the WM. That
+    ///   said, it's usually in the same ballpark as on Windows.
+    ChangeIcon(Icon),
 }
 
 impl<T> Action<T> {
@@ -108,6 +123,7 @@ impl<T> Action<T> {
                 Action::ChangeAlwaysOnTop(on_top)
             }
             Self::FetchId(o) => Action::FetchId(Box::new(move |s| f(o(s)))),
+            Self::ChangeIcon(icon) => Action::ChangeIcon(icon),
         }
     }
 }
@@ -142,6 +158,9 @@ impl<T> fmt::Debug for Action<T> {
                 write!(f, "Action::AlwaysOnTop({on_top})")
             }
             Self::FetchId(_) => write!(f, "Action::FetchId"),
+            Self::ChangeIcon(_icon) => {
+                write!(f, "Action::ChangeIcon(icon)")
+            }
         }
     }
 }