Some more updates for macOS.

- Added support for basic Cursor management.
- Added support for NSWindow cancelOperation: callbacks. It's not...
  perfect, but it works as a discrete hook.
- Added support for NSProgressIndicator.
- Properly forward Error types from QuickLook generation calls, and
  future-proof the ThumbnailQuality enum.
- Add support for configuring Label line break mode.

src/filesystem/enums.rs

@@ -24,6 +24,10 @@ impl From<NSInteger> for ModalResponse {
             -1000 => ModalResponse::Stopped,
             -1001 => ModalResponse::Aborted,
             -1002 => ModalResponse::Continue,
+
+            // @TODO: Definitely don't panic here, wtf was I thinking?
+            // Probably make this a ModalResponse::Unknown or something so a user can
+            // gracefully handle.
             e => { panic!("Unknown NSModalResponse sent back! {}", e); }
         }
     }

src/lib.rs

@@ -106,6 +106,7 @@ pub mod listview;
 pub mod networking;
 pub mod notification_center;
 pub mod pasteboard;
+pub mod progress;
 pub mod scrollview;
 pub mod text;
 

src/macos/cursor.rs

@@ -0,0 +1,85 @@
+
+use objc::{class, msg_send, sel, sel_impl};
+use crate::foundation::id;
+
+#[derive(Debug)]
+pub enum CursorType {
+    Arrow,
+    Crosshair,
+    ClosedHand,
+    OpenHand,
+    PointingHand,
+    
+    ResizeLeft,
+    ResizeRight,
+    ResizeLeftRight,
+
+    ResizeUp,
+    ResizeDown,
+    ResizeUpDown,
+
+    DisappearingItem,
+
+    IBeam,
+    IBeamVertical,
+
+    OperationNotAllowed,
+    DragLink,
+    DragCopy,
+    ContextMenu
+}
+
+#[derive(Debug)]
+pub struct Cursor;
+
+impl Cursor {
+    /// Given a cursor type, will make it the system cursor.
+    /// The inverse of this call, which you should call when ready, is `pop()`.
+    pub fn push(cursor_type: CursorType) {
+        unsafe {
+            let cursor: id = match cursor_type {
+                CursorType::Arrow => msg_send![class!(NSCursor), arrowCursor],
+                CursorType::Crosshair => msg_send![class!(NSCursor), crosshairCursor],
+                CursorType::ClosedHand => msg_send![class!(NSCursor), closedHandCursor],
+                CursorType::OpenHand => msg_send![class!(NSCursor), openHandCursor],
+                CursorType::PointingHand => msg_send![class!(NSCursor), pointingHandCursor],
+                CursorType::ResizeLeft => msg_send![class!(NSCursor), resizeLeftCursor],
+                CursorType::ResizeRight => msg_send![class!(NSCursor), resizeRightCursor],
+                CursorType::ResizeLeftRight => msg_send![class!(NSCursor), resizeLeftRightCursor],
+                CursorType::ResizeUp => msg_send![class!(NSCursor), resizeUpCursor],
+                CursorType::ResizeDown => msg_send![class!(NSCursor), resizeDownCursor],
+                CursorType::ResizeUpDown => msg_send![class!(NSCursor), resizeUpDownCursor],
+                CursorType::DisappearingItem => msg_send![class!(NSCursor), disappearingItemCursor],
+                CursorType::IBeam => msg_send![class!(NSCursor), IBeamCursor],
+                CursorType::IBeamVertical => msg_send![class!(NSCursor), IBeamCursorForVerticalLayout],
+                CursorType::OperationNotAllowed => msg_send![class!(NSCursor), operationNotAllowedCursor],
+                CursorType::DragLink => msg_send![class!(NSCursor), dragLinkCursor],
+                CursorType::DragCopy => msg_send![class!(NSCursor), dragCopyCursor],
+                CursorType::ContextMenu => msg_send![class!(NSCursor), contextualMenuCursor]
+            };
+            
+            let _: () = msg_send![cursor, push];
+        }
+    }
+
+    /// Pops the current cursor off the cursor-stack. The inverse of push.
+    pub fn pop() {
+        unsafe {
+            let _: () = msg_send![class!(NSCursor), pop];
+        }
+    }
+
+    /// Hides the cursor. Part of a balanced call stack.
+    pub fn hide() {
+        unsafe {
+            let _: () = msg_send![class!(NSCursor), hide];
+        }
+    }
+
+    /// Un-hides the cursor. Part of a balanced call stack.
+    pub fn unhide() {
+        unsafe {
+            let _: () = msg_send![class!(NSCursor), unhide];
+        }
+    }
+}

src/macos/mod.rs

@@ -21,6 +21,9 @@ pub use alert::Alert;
 mod app;
 pub use app::*;
 
+mod cursor;
+pub use cursor::{Cursor, CursorType};
+
 pub mod menu;
 pub mod printing;
 pub mod toolbar;

src/macos/window/class.rs

@@ -219,6 +219,15 @@ extern fn did_expose<T: WindowDelegate>(this: &Object, _: Sel, _: id) {
     window.did_expose();
 }
 
+/// Called as part of the responder chain, when, say, the ESC key is hit. If your 
+/// delegate returns `true` in `should_cancel_on_esc`, then this will allow your
+/// window to close when the Esc key is hit. This is mostly useful for Sheet-presented
+/// windows, and so the default response from delegates is `false` and must be opted in to.
+extern fn cancel<T: WindowDelegate>(this: &Object, _: Sel, _: id) {
+    let window = load::<T>(this, WINDOW_DELEGATE_PTR);
+    window.cancel();
+}
+
 /// Injects an `NSWindow` subclass, with some callback and pointer ivars for what we
 /// need to do.
 pub(crate) fn register_window_class() -> *const Class {
@@ -292,6 +301,7 @@ pub(crate) fn register_window_class_with_delegate<T: WindowDelegate>() -> *const
         decl.add_method(sel!(windowDidChangeOcclusionState:), did_change_occlusion_state::<T> as extern fn(&Object, _, _));
         decl.add_method(sel!(windowDidExpose:), did_expose::<T> as extern fn(&Object, _, _));
         decl.add_method(sel!(windowDidUpdate:), did_update::<T> as extern fn(&Object, _, _));
+        decl.add_method(sel!(cancelOperation:), cancel::<T> as extern fn (&Object, _, _));
         
         DELEGATE_CLASS = decl.register();
     });

src/macos/window/controller/mod.rs

@@ -52,7 +52,7 @@ impl<T> WindowController<T> where T: WindowDelegate + 'static {
     /// Allocates and configures an `NSWindowController` in the Objective-C/Cocoa runtime that maps over
     /// to your supplied delegate.
     pub fn with(config: WindowConfig, delegate: T) -> Self {
-        let window = Window::with(config, delegate);
+        let mut window = Window::with(config, delegate);
 
         let objc = unsafe {
             let window_controller_class = register_window_controller_class::<T>();
@@ -67,7 +67,7 @@ impl<T> WindowController<T> where T: WindowDelegate + 'static {
             ShareId::from_ptr(controller)
         };
 
-        if let Some(delegate) = &window.delegate {
+        if let Some(delegate) = &mut window.delegate {
             (*delegate).did_load(Window {
                 delegate: None,
                 objc: window.objc.clone()

src/macos/window/mod.rs

@@ -10,10 +10,12 @@
 
 use std::unreachable;
 
+use block::ConcreteBlock;
+
 use core_graphics::base::CGFloat;
 use core_graphics::geometry::{CGRect, CGSize};
 
-use objc::{msg_send, sel, sel_impl};
+use objc::{msg_send, sel, sel_impl, class};
 use objc::runtime::Object;
 use objc_id::ShareId;
 
@@ -66,6 +68,11 @@ impl Window {
     /// after we initialize the backing `NSWindow`.
     pub fn new(config: WindowConfig) -> Window {
         let objc = unsafe {
+            // This behavior might make sense to keep as default (YES), but I think the majority of
+            // apps that would use this toolkit wouldn't be tab-oriented...
+            let _: () = msg_send![class!(NSWindow), setAllowsAutomaticWindowTabbing:NO];
+
+
             let alloc: id = msg_send![register_window_class(), alloc];
             
             // Other types of backing (Retained/NonRetained) are archaic, dating back to the
@@ -105,9 +112,14 @@ impl<T> Window<T> where T: WindowDelegate + 'static {
     /// enables easier structure of your codebase, and in a way simulates traditional class based
     /// architectures... just without the subclassing.
     pub fn with(config: WindowConfig, delegate: T) -> Self {
-        let delegate = Box::new(delegate);
+        let mut delegate = Box::new(delegate);
         
         let objc = unsafe {
+            // This behavior might make sense to keep as default (YES), but I think the majority of
+            // apps that would use this toolkit wouldn't be tab-oriented...
+            let _: () = msg_send![class!(NSWindow), setAllowsAutomaticWindowTabbing:NO];
+
+
             let alloc: id = msg_send![register_window_class_with_delegate::<T>(), alloc];
             
             // Other types of backing (Retained/NonRetained) are archaic, dating back to the
@@ -143,7 +155,7 @@ impl<T> Window<T> where T: WindowDelegate + 'static {
         };
 
         {
-            &delegate.did_load(Window {
+            (&mut delegate).did_load(Window {
                 delegate: None,
                 objc: objc.clone()
             });
@@ -447,6 +459,37 @@ impl<T> Window<T> {
             scale as f64
         }
     }
+
+    /// Given a window and callback handler, will run it as a "sheet" (model-ish) and then run the
+    /// handler once the sheet is dismissed.
+    ///
+    /// This is a bit awkward due to Rust semantics; you have to use the same type of Window as the
+    /// one you're presenting on, but in practice this isn't too bad since you rarely want a Window
+    /// without a WindowDelegate.
+    pub fn begin_sheet<F, W>(&self, window: &Window<W>, completion: F)
+    where
+        F: Fn() + Send + Sync + 'static,
+        W: WindowDelegate + 'static
+    {
+        let block = ConcreteBlock::new(move |response: NSInteger| {
+            completion();
+        });
+        let block = block.copy();
+
+        unsafe {
+            let _: () = msg_send![&*self.objc, beginSheet:&*window.objc completionHandler:block];
+        }
+    }
+
+    /// Closes a sheet.
+    pub fn end_sheet<W>(&self, window: &Window<W>)
+    where
+        W: WindowDelegate + 'static
+    {
+        unsafe {
+            let _: () = msg_send![&*self.objc, endSheet:&*window.objc];
+        }
+    }
 }
 
 impl<T> Drop for Window<T> {

src/macos/window/traits.rs

@@ -13,7 +13,7 @@ pub trait WindowDelegate {
     /// to set up your views and what not.
     ///
     /// If you're coming from the web, you can think of this as `DOMContentLoaded`.
-    fn did_load(&self, _window: Window) {}
+    fn did_load(&mut self, _window: Window) {}
 
     /// Called when the user has attempted to close the window. NOT called when a user quits the
     /// application. Return false here if you need to handle the edge case.
@@ -118,4 +118,8 @@ pub trait WindowDelegate {
 
     /// Fired when the Window receives an `update` message from higher up in the chain.
     fn did_update(&self) {}
+
+    /// If you want your window to close when the `ESC` key is hit, implement this.
+    /// This is mostly useful for windows that present as modal sheets.
+    fn cancel(&self) {}
 }

src/progress/enums.rs

@@ -0,0 +1,20 @@
+use crate::foundation::{NSUInteger};
+
+/// The type of spinner style you're after.
+#[derive(Debug)]
+pub enum ProgressIndicatorStyle {
+    /// A loading bar.
+    Bar,
+
+    /// A spinning circle.
+    Spinner
+}
+
+impl From<ProgressIndicatorStyle> for NSUInteger {
+    fn from(style: ProgressIndicatorStyle) -> Self {
+        match style {
+            ProgressIndicatorStyle::Bar => 0,
+            ProgressIndicatorStyle::Spinner => 1
+        }
+    }
+}

src/progress/ios.rs

@@ -0,0 +1,45 @@
+use std::sync::Once;
+
+use objc::declare::ClassDecl;
+use objc::runtime::{Class, Object, Sel, BOOL};
+use objc::{class, sel, sel_impl};
+use objc_id::Id;
+
+use crate::foundation::{id, YES, NO, NSUInteger};
+use crate::dragdrop::DragInfo;
+use crate::view::{VIEW_DELEGATE_PTR, ViewDelegate};
+use crate::utils::load;
+
+/// Injects an `NSView` subclass. This is used for the default views that don't use delegates - we
+/// have separate classes here since we don't want to waste cycles on methods that will never be
+/// used if there's no delegates.
+pub(crate) fn register_view_class() -> *const Class {
+    static mut VIEW_CLASS: *const Class = 0 as *const Class;
+    static INIT: Once = Once::new();
+
+    INIT.call_once(|| unsafe {
+        let superclass = class!(UIView);
+        let mut decl = ClassDecl::new("RSTView", superclass).unwrap();
+        VIEW_CLASS = decl.register();
+    });
+
+    unsafe { VIEW_CLASS }
+}
+
+/// Injects an `NSView` subclass, with some callback and pointer ivars for what we
+/// need to do.
+pub(crate) fn register_view_class_with_delegate<T: ViewDelegate>() -> *const Class {
+    static mut VIEW_CLASS: *const Class = 0 as *const Class;
+    static INIT: Once = Once::new();
+
+    INIT.call_once(|| unsafe {
+        let superclass = class!(UIView);
+        let mut decl = ClassDecl::new("RSTViewWithDelegate", superclass).unwrap();
+        decl.add_ivar::<usize>(VIEW_DELEGATE_PTR);
+        VIEW_CLASS = decl.register();
+    });
+
+    unsafe {
+        VIEW_CLASS
+    }
+}

src/progress/macos.rs

@@ -0,0 +1,21 @@
+use std::sync::Once;
+
+use objc::declare::ClassDecl;
+use objc::runtime::{Class, Object, Sel, BOOL};
+use objc::{class, sel, sel_impl};
+
+/// Injects an `NSView` subclass. This is used for the default views that don't use delegates - we
+/// have separate classes here since we don't want to waste cycles on methods that will never be
+/// used if there's no delegates.
+pub(crate) fn register_progress_indicator_class() -> *const Class {
+    static mut VIEW_CLASS: *const Class = 0 as *const Class;
+    static INIT: Once = Once::new();
+
+    INIT.call_once(|| unsafe {
+        let superclass = class!(NSProgressIndicator);
+        let decl = ClassDecl::new("RSTProgressIndicator", superclass).unwrap();
+        VIEW_CLASS = decl.register();
+    });
+
+    unsafe { VIEW_CLASS }
+}

src/progress/mod.rs

@@ -0,0 +1,166 @@
+use objc_id::ShareId;
+use objc::runtime::{Class, Object};
+use objc::{msg_send, sel, sel_impl};
+
+use crate::foundation::{id, nil, YES, NO, NSUInteger};
+use crate::color::Color;
+use crate::layout::{Layout, LayoutAnchorX, LayoutAnchorY, LayoutAnchorDimension};
+
+#[cfg(target_os = "macos")]
+mod macos;
+
+#[cfg(target_os = "macos")]
+use macos::{register_progress_indicator_class};
+
+#[cfg(target_os = "ios")]
+mod ios;
+
+#[cfg(target_os = "ios")]
+use ios::{register_progress_indicator_class};
+
+mod enums;
+pub use enums::ProgressIndicatorStyle;
+
+#[derive(Debug)]
+pub struct ProgressIndicator {
+    /// A pointer to the Objective-C runtime view controller.
+    pub objc: ShareId<Object>,
+
+    /// A pointer to the Objective-C runtime top layout constraint.
+    pub top: LayoutAnchorY,
+
+    /// A pointer to the Objective-C runtime leading layout constraint.
+    pub leading: LayoutAnchorX,
+
+    /// A pointer to the Objective-C runtime trailing layout constraint.
+    pub trailing: LayoutAnchorX,
+
+    /// A pointer to the Objective-C runtime bottom layout constraint.
+    pub bottom: LayoutAnchorY,
+
+    /// A pointer to the Objective-C runtime width layout constraint.
+    pub width: LayoutAnchorDimension,
+
+    /// A pointer to the Objective-C runtime height layout constraint.
+    pub height: LayoutAnchorDimension,
+
+    /// A pointer to the Objective-C runtime center X layout constraint.
+    pub center_x: LayoutAnchorX,
+
+    /// A pointer to the Objective-C runtime center Y layout constraint.
+    pub center_y: LayoutAnchorY
+}
+
+impl Default for ProgressIndicator {
+    fn default() -> Self {
+        ProgressIndicator::new()
+    }
+}
+
+impl ProgressIndicator {
+    /// Returns a default `ProgressIndicator`, suitable for 
+    pub fn new() -> Self {
+        let view = unsafe {
+            let view: id = msg_send![register_progress_indicator_class(), new];
+            let _: () = msg_send![view, setTranslatesAutoresizingMaskIntoConstraints:NO];
+
+            #[cfg(target_os = "macos")]
+            let _: () = msg_send![view, setWantsLayer:YES];
+
+            view
+        };
+
+        ProgressIndicator {
+            top: LayoutAnchorY::new(unsafe { msg_send![view, topAnchor] }),
+            leading: LayoutAnchorX::new(unsafe { msg_send![view, leadingAnchor] }),
+            trailing: LayoutAnchorX::new(unsafe { msg_send![view, trailingAnchor] }),
+            bottom: LayoutAnchorY::new(unsafe { msg_send![view, bottomAnchor] }),
+            width: LayoutAnchorDimension::new(unsafe { msg_send![view, widthAnchor] }),
+            height: LayoutAnchorDimension::new(unsafe { msg_send![view, heightAnchor] }),
+            center_x: LayoutAnchorX::new(unsafe { msg_send![view, centerXAnchor] }),
+            center_y: LayoutAnchorY::new(unsafe { msg_send![view, centerYAnchor] }),
+            objc: unsafe { ShareId::from_ptr(view) },
+        }
+    }
+}
+
+impl ProgressIndicator {
+    /// Call this to set the background color for the backing layer.
+    pub fn set_background_color(&self, color: Color) {
+        let bg = color.into_platform_specific_color();
+        
+        unsafe {
+            let cg: id = msg_send![bg, CGColor];
+            let layer: id = msg_send![&*self.objc, layer];
+            let _: () = msg_send![layer, setBackgroundColor:cg];
+        }
+    }
+
+    /// Starts the animation for an indeterminate indicator.
+    pub fn start_animation(&self) {
+        unsafe {
+            let _: () = msg_send![&*self.objc, startAnimation:nil];
+        }
+    }
+
+    pub fn stop_animation(&self) {
+        unsafe {
+            let _: () = msg_send![&*self.objc, stopAnimation:nil];
+        }
+    }
+
+    pub fn increment(&self, by: f64) {
+        unsafe {
+            let _: () = msg_send![&*self.objc, incrementBy:by];
+        }
+    }
+
+    pub fn set_style(&self, style: ProgressIndicatorStyle) {
+        unsafe {
+            let style = style as NSUInteger;
+            let _: () = msg_send![&*self.objc, setStyle:style];
+        }
+    }
+
+    pub fn set_indeterminate(&self, is_indeterminate: bool) {
+        unsafe {
+            let _: () = msg_send![&*self.objc, setIndeterminate:match is_indeterminate {
+                true => YES,
+                false => NO
+            }];
+        }
+    }
+}
+
+impl Layout for ProgressIndicator {
+    fn get_backing_node(&self) -> ShareId<Object> {
+        self.objc.clone()
+    }
+
+    fn add_subview<V: Layout>(&self, view: &V) {
+        let backing_node = view.get_backing_node();
+
+        unsafe {
+            let _: () = msg_send![&*self.objc, addSubview:backing_node];
+        }
+    }
+}
+
+impl Drop for ProgressIndicator {
+    /// A bit of extra cleanup for delegate callback pointers. If the originating `ProgressIndicator` is being
+    /// dropped, we do some logic to clean it all up (e.g, we go ahead and check to see if
+    /// this has a superview (i.e, it's in the heirarchy) on the AppKit side. If it does, we go
+    /// ahead and remove it - this is intended to match the semantics of how Rust handles things).
+    ///
+    /// There are, thankfully, no delegates we need to break here.
+    fn drop(&mut self) {
+        /*if self.delegate.is_some() {
+            unsafe {
+                let superview: id = msg_send![&*self.objc, superview];
+                if superview != nil {
+                    let _: () = msg_send![&*self.objc, removeFromSuperview];
+                }
+            }
+        }*/
+    }
+}

src/quicklook/config.rs

@@ -23,7 +23,12 @@ pub enum ThumbnailQuality {
 
     /// Ask for them all, and pick which one you
     /// use via your provided callback.
-    All
+    All,
+
+    /// Provided in case this is ever expanded by the OS, and the system
+    /// returns a thumbnail quality type that can't be matched here. Users
+    /// could then handle the edge case themselves.
+    Unknown(NSUInteger)
 }
 
 impl From<&ThumbnailQuality> for NSUInteger {
@@ -32,11 +37,35 @@ impl From<&ThumbnailQuality> for NSUInteger {
             ThumbnailQuality::Icon => 1 << 0,
             ThumbnailQuality::Low => 1 << 1,
             ThumbnailQuality::High => 1 << 2,
-            ThumbnailQuality::All => NSUInteger::MAX
+            ThumbnailQuality::All => NSUInteger::MAX,
+            ThumbnailQuality::Unknown(x) => *x
         }
     }
 }
 
+impl From<ThumbnailQuality> for NSUInteger {
+    fn from(quality: ThumbnailQuality) -> Self {
+        match quality {
+            ThumbnailQuality::Icon => 1 << 0,
+            ThumbnailQuality::Low => 1 << 1,
+            ThumbnailQuality::High => 1 << 2,
+            ThumbnailQuality::All => NSUInteger::MAX,
+            ThumbnailQuality::Unknown(x) => x
+        }
+    }
+}
+
+impl From<NSUInteger> for ThumbnailQuality {
+    fn from(i: NSUInteger) -> Self {
+        match i {
+            0 => ThumbnailQuality::Icon,
+            2 => ThumbnailQuality::Low,
+            4 => ThumbnailQuality::High,
+            NSUInteger::MAX => ThumbnailQuality::All,
+            i => ThumbnailQuality::Unknown(i)
+        }
+    }
+}
 
 #[derive(Clone, Debug)]
 pub struct ThumbnailConfig {

src/quicklook/mod.rs

@@ -7,7 +7,7 @@ use block::ConcreteBlock;
 use url::Url;
 
 use crate::error::Error;
-use crate::foundation::{id, NSUInteger};
+use crate::foundation::{id, nil, NSUInteger};
 use crate::image::Image;
 
 mod config;
@@ -25,13 +25,18 @@ impl ThumbnailGenerator {
 
     pub fn generate<F>(&self, url: &Url, config: ThumbnailConfig, callback: F)
     where
-        //F: Fn(Result<(Image, ThumbnailQuality), Error>) + Send + Sync + 'static
         F: Fn(Result<(Image, ThumbnailQuality), Error>) + Send + Sync + 'static
     {
         let block = ConcreteBlock::new(move |thumbnail: id, thumbnail_type: NSUInteger, error: id| {
-            unsafe {
-                let image = Image::with(msg_send![thumbnail, NSImage]);
-                callback(Ok((image, ThumbnailQuality::Low)));
+            if error == nil {
+                unsafe {
+                    let image = Image::with(msg_send![thumbnail, NSImage]);
+                    let quality = ThumbnailQuality::from(thumbnail_type);
+                    callback(Ok((image, ThumbnailQuality::Low)));
+                }
+            } else {
+                let error = Error::new(error);
+                callback(Err(error));
             }
         });
 

src/text/enums.rs

@@ -20,3 +20,39 @@ impl From<TextAlign> for NSInteger {
         }
     }
 }
+
+/// Instructs text controls how to optimize line breaks.
+pub enum LineBreakMode {
+    /// Wrap at word boundaries (the default)
+    WrapWords,
+
+    /// Wrap at character boundaries
+    WrapChars,
+
+    /// Clip with no regard
+    Clip,
+
+    /// Truncate the start, e.g, ...my sentence
+    TruncateHead,
+
+    /// Truncate the end, e.g, my sentenc...
+    TruncateTail,
+
+    /// Truncate the middle, e.g, my se...ce
+    TruncateMiddle
+}
+
+impl Into<NSUInteger> for LineBreakMode {
+    fn into(self) -> NSUInteger {
+        match self {
+            LineBreakMode::WrapWords => 0,
+            LineBreakMode::WrapChars => 1,
+            LineBreakMode::Clip => 2,
+            LineBreakMode::TruncateHead => 3,
+            LineBreakMode::TruncateTail => 4,
+            LineBreakMode::TruncateMiddle => 5
+        }
+    }
+}
+
+

src/text/label/mod.rs

@@ -44,10 +44,10 @@ use objc_id::ShareId;
 use objc::runtime::{Class, Object};
 use objc::{msg_send, sel, sel_impl};
 
-use crate::foundation::{id, nil, YES, NO, NSArray, NSInteger, NSString};
+use crate::foundation::{id, nil, YES, NO, NSArray, NSInteger, NSUInteger, NSString};
 use crate::color::Color;
 use crate::layout::{Layout, LayoutAnchorX, LayoutAnchorY, LayoutAnchorDimension};
-use crate::text::{Font, TextAlign};
+use crate::text::{Font, TextAlign, LineBreakMode};
 
 #[cfg(target_os = "macos")]
 mod macos;
@@ -237,6 +237,15 @@ impl<T> Label<T> {
             let _: () = msg_send![&*self.objc, setFont:&*font.objc];
         }
     }
+
+    pub fn set_line_break_mode(&self, mode: LineBreakMode) {
+        #[cfg(target_os = "macos")]
+        unsafe {
+            let cell: id = msg_send![&*self.objc, cell];
+            let mode = mode as NSUInteger;
+            let _: () = msg_send![cell, setLineBreakMode:mode];
+        }
+    }
 }
 
 impl<T> Layout for Label<T> {

src/text/mod.rs

@@ -5,7 +5,7 @@ pub mod label;
 pub use label::Label;
 
 pub mod enums;
-pub use enums::TextAlign;
+pub use enums::{LineBreakMode, TextAlign};
 
 pub mod font;
 pub use font::Font;