Support pinch, double tap and rotation gestures on iOS (#3130)

This is off by default on iOS. Note that pinch delta may be NaN.

Co-authored-by: Mads Marquart <mads@marquart.dk>

src/platform_impl/ios/uikit/gesture_recognizer.rs

@@ -0,0 +1,121 @@
+use icrate::Foundation::{CGFloat, NSInteger, NSObject, NSUInteger};
+use objc2::{
+    encode::{Encode, Encoding},
+    extern_class, extern_methods, mutability, ClassType,
+};
+
+// https://developer.apple.com/documentation/uikit/uigesturerecognizer
+extern_class!(
+    #[derive(Debug, PartialEq, Eq, Hash)]
+    pub(crate) struct UIGestureRecognizer;
+
+    unsafe impl ClassType for UIGestureRecognizer {
+        type Super = NSObject;
+        type Mutability = mutability::InteriorMutable;
+    }
+);
+
+extern_methods!(
+    unsafe impl UIGestureRecognizer {
+        #[method(state)]
+        pub fn state(&self) -> UIGestureRecognizerState;
+    }
+);
+
+unsafe impl Encode for UIGestureRecognizer {
+    const ENCODING: Encoding = Encoding::Object;
+}
+
+// https://developer.apple.com/documentation/uikit/uigesturerecognizer/state
+#[repr(transparent)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub struct UIGestureRecognizerState(NSInteger);
+
+unsafe impl Encode for UIGestureRecognizerState {
+    const ENCODING: Encoding = NSInteger::ENCODING;
+}
+
+#[allow(dead_code)]
+impl UIGestureRecognizerState {
+    pub const Possible: Self = Self(0);
+    pub const Began: Self = Self(1);
+    pub const Changed: Self = Self(2);
+    pub const Ended: Self = Self(3);
+    pub const Cancelled: Self = Self(4);
+    pub const Failed: Self = Self(5);
+}
+
+// https://developer.apple.com/documentation/uikit/uipinchgesturerecognizer
+extern_class!(
+    #[derive(Debug, PartialEq, Eq, Hash)]
+    pub(crate) struct UIPinchGestureRecognizer;
+
+    unsafe impl ClassType for UIPinchGestureRecognizer {
+        type Super = UIGestureRecognizer;
+        type Mutability = mutability::InteriorMutable;
+    }
+);
+
+extern_methods!(
+    unsafe impl UIPinchGestureRecognizer {
+        #[method(scale)]
+        pub fn scale(&self) -> CGFloat;
+
+        #[method(velocity)]
+        pub fn velocity(&self) -> CGFloat;
+    }
+);
+
+unsafe impl Encode for UIPinchGestureRecognizer {
+    const ENCODING: Encoding = Encoding::Object;
+}
+
+// https://developer.apple.com/documentation/uikit/uirotationgesturerecognizer
+extern_class!(
+    #[derive(Debug, PartialEq, Eq, Hash)]
+    pub(crate) struct UIRotationGestureRecognizer;
+
+    unsafe impl ClassType for UIRotationGestureRecognizer {
+        type Super = UIGestureRecognizer;
+        type Mutability = mutability::InteriorMutable;
+    }
+);
+
+extern_methods!(
+    unsafe impl UIRotationGestureRecognizer {
+        #[method(rotation)]
+        pub fn rotation(&self) -> CGFloat;
+
+        #[method(velocity)]
+        pub fn velocity(&self) -> CGFloat;
+    }
+);
+
+unsafe impl Encode for UIRotationGestureRecognizer {
+    const ENCODING: Encoding = Encoding::Object;
+}
+
+// https://developer.apple.com/documentation/uikit/uitapgesturerecognizer
+extern_class!(
+    #[derive(Debug, PartialEq, Eq, Hash)]
+    pub(crate) struct UITapGestureRecognizer;
+
+    unsafe impl ClassType for UITapGestureRecognizer {
+        type Super = UIGestureRecognizer;
+        type Mutability = mutability::InteriorMutable;
+    }
+);
+
+extern_methods!(
+    unsafe impl UITapGestureRecognizer {
+        #[method(setNumberOfTapsRequired:)]
+        pub fn setNumberOfTapsRequired(&self, number_of_taps_required: NSUInteger);
+
+        #[method(setNumberOfTouchesRequired:)]
+        pub fn setNumberOfTouchesRequired(&self, number_of_touches_required: NSUInteger);
+    }
+);
+
+unsafe impl Encode for UITapGestureRecognizer {
+    const ENCODING: Encoding = Encoding::Object;
+}

src/platform_impl/ios/uikit/mod.rs

@@ -9,6 +9,7 @@ mod application;
 mod coordinate_space;
 mod device;
 mod event;
+mod gesture_recognizer;
 mod responder;
 mod screen;
 mod screen_mode;
@@ -23,6 +24,10 @@ pub(crate) use self::application::UIApplication;
 pub(crate) use self::coordinate_space::UICoordinateSpace;
 pub(crate) use self::device::UIDevice;
 pub(crate) use self::event::UIEvent;
+pub(crate) use self::gesture_recognizer::{
+    UIGestureRecognizer, UIGestureRecognizerState, UIPinchGestureRecognizer,
+    UIRotationGestureRecognizer, UITapGestureRecognizer,
+};
 pub(crate) use self::responder::UIResponder;
 pub(crate) use self::screen::{UIScreen, UIScreenOverscanCompensation};
 pub(crate) use self::screen_mode::UIScreenMode;

src/platform_impl/ios/uikit/view.rs

@@ -3,7 +3,7 @@ use objc2::encode::{Encode, Encoding};
 use objc2::rc::Id;
 use objc2::{extern_class, extern_methods, msg_send_id, mutability, ClassType};
 
-use super::{UICoordinateSpace, UIResponder, UIViewController};
+use super::{UICoordinateSpace, UIGestureRecognizer, UIResponder, UIViewController};
 
 extern_class!(
     #[derive(Debug, PartialEq, Eq, Hash)]
@@ -65,6 +65,12 @@ extern_methods!(
 
         #[method(setNeedsDisplay)]
         pub fn setNeedsDisplay(&self);
+
+        #[method(addGestureRecognizer:)]
+        pub fn addGestureRecognizer(&self, gestureRecognizer: &UIGestureRecognizer);
+
+        #[method(removeGestureRecognizer:)]
+        pub fn removeGestureRecognizer(&self, gestureRecognizer: &UIGestureRecognizer);
     }
 );