add stepper

src/lib.rs

@@ -172,6 +172,9 @@ pub mod switch;
 #[cfg(feature = "appkit")]
 pub mod select;
 
+#[cfg(feature = "appkit")]
+pub mod stepper;
+
 pub mod text;
 
 #[cfg(feature = "quicklook")]

src/stepper/mod.rs

@@ -0,0 +1,227 @@
+//! Implements a number stepper. By default this uses NSStepper on macOS.
+
+use core_graphics::geometry::CGRect;
+use objc::rc::{Id, Shared};
+use objc::runtime::{Class, Object};
+use objc::{msg_send, msg_send_id, sel};
+
+use crate::control::Control;
+use crate::foundation::{id, load_or_register_class, nil, NSInteger, NSNumber, NSString, NO, YES};
+use crate::geometry::Rect;
+use crate::invoker::TargetActionHandler;
+use crate::layout::Layout;
+#[cfg(feature = "autolayout")]
+use crate::layout::{LayoutAnchorDimension, LayoutAnchorX, LayoutAnchorY};
+use crate::objc_access::ObjcAccess;
+use crate::utils::properties::ObjcProperty;
+
+/// Wraps `NSStepper` on AppKit. Not currently implemented for iOS.
+#[derive(Debug)]
+pub struct Stepper {
+    /// A handle for the underlying Objective-C object.
+    pub objc: ObjcProperty,
+
+    handler: Option<TargetActionHandler>,
+
+    /// A pointer to the Objective-C runtime top layout constraint.
+    #[cfg(feature = "autolayout")]
+    pub top: LayoutAnchorY,
+
+    /// A pointer to the Objective-C runtime leading layout constraint.
+    #[cfg(feature = "autolayout")]
+    pub leading: LayoutAnchorX,
+
+    /// A pointer to the Objective-C runtime left layout constraint.
+    #[cfg(feature = "autolayout")]
+    pub left: LayoutAnchorX,
+
+    /// A pointer to the Objective-C runtime trailing layout constraint.
+    #[cfg(feature = "autolayout")]
+    pub trailing: LayoutAnchorX,
+
+    /// A pointer to the Objective-C runtime right layout constraint.
+    #[cfg(feature = "autolayout")]
+    pub right: LayoutAnchorX,
+
+    /// A pointer to the Objective-C runtime bottom layout constraint.
+    #[cfg(feature = "autolayout")]
+    pub bottom: LayoutAnchorY,
+
+    /// A pointer to the Objective-C runtime width layout constraint.
+    #[cfg(feature = "autolayout")]
+    pub width: LayoutAnchorDimension,
+
+    /// A pointer to the Objective-C runtime height layout constraint.
+    #[cfg(feature = "autolayout")]
+    pub height: LayoutAnchorDimension,
+
+    /// A pointer to the Objective-C runtime center X layout constraint.
+    #[cfg(feature = "autolayout")]
+    pub center_x: LayoutAnchorX,
+
+    /// A pointer to the Objective-C runtime center Y layout constraint.
+    #[cfg(feature = "autolayout")]
+    pub center_y: LayoutAnchorY,
+}
+
+impl Stepper {
+    /// Creates a new `Stepper` instance, configures it appropriately,
+    /// and retains the necessary Objective-C runtime pointer.
+    pub fn new() -> Self {
+        let zero: CGRect = Rect::zero().into();
+
+        let view: id = unsafe {
+            let alloc: id = msg_send![register_class(), alloc];
+            let stepper: id = msg_send![alloc, initWithFrame:zero];
+
+            #[cfg(feature = "autolayout")]
+            let _: () = msg_send![stepper, setTranslatesAutoresizingMaskIntoConstraints: NO];
+
+            stepper
+        };
+
+        Stepper {
+            handler: None,
+
+            #[cfg(feature = "autolayout")]
+            top: LayoutAnchorY::top(view),
+
+            #[cfg(feature = "autolayout")]
+            left: LayoutAnchorX::left(view),
+
+            #[cfg(feature = "autolayout")]
+            leading: LayoutAnchorX::leading(view),
+
+            #[cfg(feature = "autolayout")]
+            right: LayoutAnchorX::right(view),
+
+            #[cfg(feature = "autolayout")]
+            trailing: LayoutAnchorX::trailing(view),
+
+            #[cfg(feature = "autolayout")]
+            bottom: LayoutAnchorY::bottom(view),
+
+            #[cfg(feature = "autolayout")]
+            width: LayoutAnchorDimension::width(view),
+
+            #[cfg(feature = "autolayout")]
+            height: LayoutAnchorDimension::height(view),
+
+            #[cfg(feature = "autolayout")]
+            center_x: LayoutAnchorX::center(view),
+
+            #[cfg(feature = "autolayout")]
+            center_y: LayoutAnchorY::center(view),
+
+            objc: ObjcProperty::retain(view),
+        }
+    }
+
+    /// Attaches a callback
+    pub fn set_action<F: Fn(*const Object) + Send + Sync + 'static>(&mut self, action: F) {
+        // @TODO: This probably isn't ideal but gets the job done for now; needs revisiting.
+        let this: Id<Object, Shared> = self.objc.get(|obj| unsafe { msg_send_id![obj, self] });
+        let handler = TargetActionHandler::new(&this, action);
+        self.handler = Some(handler);
+    }
+
+    /// Sets maximum value
+    pub fn set_max_value(&self, value: f64) {
+        self.objc.with_mut(|obj| unsafe {
+            let _: () = msg_send![obj, setMaxValue: value];
+        });
+    }
+
+    /// Sets minimum value
+    pub fn set_min_value(&self, value: f64) {
+        self.objc.with_mut(|obj| unsafe {
+            let _: () = msg_send![obj, setMinValue: value];
+        });
+    }
+
+    /// Sets increment
+    pub fn set_increment(&self, value: f64) {
+        self.objc.with_mut(|obj| unsafe {
+            let _: () = msg_send![obj, setIncrement: value];
+        });
+    }
+
+    /// Sets whether this wraps
+    pub fn set_wraps(&self, wraps: bool) {
+        self.objc.with_mut(|obj| unsafe {
+            let _: () = msg_send![obj, setValueWraps:match wraps {
+                true => YES,
+                false => NO
+            }];
+        });
+    }
+
+    /// Gets the selected index.
+    pub fn get_selected_value(&self) -> f32 {
+        self.objc.get(|obj| unsafe { msg_send![obj, floatValue] })
+    }
+}
+
+impl ObjcAccess for Stepper {
+    fn with_backing_obj_mut<F: Fn(id)>(&self, handler: F) {
+        self.objc.with_mut(handler);
+    }
+
+    fn get_from_backing_obj<F: Fn(&Object) -> R, R>(&self, handler: F) -> R {
+        self.objc.get(handler)
+    }
+}
+
+impl Layout for Stepper {
+    fn add_subview<V: Layout>(&self, _view: &V) {
+        panic!(
+            r#"
+            Tried to add a subview to a Stepper. This is not allowed in Cacao. If you think this should be supported,
+            open a discussion on the GitHub repo.
+        "#
+        );
+    }
+}
+
+impl Control for Stepper {}
+
+impl ObjcAccess for &Stepper {
+    fn with_backing_obj_mut<F: Fn(id)>(&self, handler: F) {
+        self.objc.with_mut(handler);
+    }
+
+    fn get_from_backing_obj<F: Fn(&Object) -> R, R>(&self, handler: F) -> R {
+        self.objc.get(handler)
+    }
+}
+
+impl Layout for &Stepper {
+    fn add_subview<V: Layout>(&self, _view: &V) {
+        panic!(
+            r#"
+            Tried to add a subview to a Stepper. This is not allowed in Cacao. If you think this should be supported,
+            open a discussion on the GitHub repo.
+        "#
+        );
+    }
+}
+
+impl Control for &Stepper {}
+
+impl Drop for Stepper {
+    /// Nils out references on the Objective-C side and removes this from the backing view.
+    // Just to be sure, let's... nil these out. They should be weak references,
+    // but I'd rather be paranoid and remove them later.
+    fn drop(&mut self) {
+        self.objc.with_mut(|obj| unsafe {
+            let _: () = msg_send![obj, setTarget: nil];
+            let _: () = msg_send![obj, setAction: nil];
+        });
+    }
+}
+
+/// Registers an `NSStepper` subclass, and configures it to hold some ivars
+/// for various things we need to store.
+fn register_class() -> &'static Class {
+    load_or_register_class("NSStepper", "CacaoStepper", |decl| unsafe {})
+}