diff --git a/src/appkit.rs b/src/appkit.rs
index 00e017d..62eca8f 100644
--- a/src/appkit.rs
+++ b/src/appkit.rs
@@ -224,6 +224,16 @@ pub enum NSEventType {
     NSEventTypeEndGesture   = 20,
 }
 
+#[repr(u64)]
+pub enum NSEventSubtype {
+    NSWindowExposedEventType            = 0,
+    NSApplicationActivatedEventType     = 1,
+    NSApplicationDeactivatedEventType   = 2,
+    NSWindowMovedEventType              = 4,
+    NSScreenChangedEventType            = 8,
+    NSAWTEventType                      = 16,
+}
+
 #[repr(u64)]
 pub enum NSEventMask {
     NSLeftMouseDownMask         = 1 << NSLeftMouseDown as uint,
@@ -473,6 +483,7 @@ pub trait NSWindow {
 
     unsafe fn setContentView_(self, view: id);
     unsafe fn setAcceptsMouseMovedEvents_(self, accept: bool);
+    unsafe fn isVisible(self) -> bool;
 }
 
 impl NSWindow for id {
@@ -736,6 +747,10 @@ impl NSWindow for id {
     unsafe fn setAcceptsMouseMovedEvents_(self, accept: bool) {
         self.send_void("setAcceptsMouseMovedEvents:", accept);
     }
+
+    unsafe fn isVisible(self) -> bool {
+        self.send_bool("isVisible", ())
+    }
 }
 
 pub trait NSString {
@@ -746,6 +761,7 @@ pub trait NSString {
     unsafe fn initWithUTF8String_(self, c_string: *const u8) -> id;
     unsafe fn stringByAppendingString_(self, other: id) -> id;
     unsafe fn init_str(self, string: &str) -> Self;
+    unsafe fn UTF8String(self) -> *const libc::c_char;
 }
 
 impl NSString for id {
@@ -760,6 +776,10 @@ impl NSString for id {
     unsafe fn init_str(self, string: &str) -> id {
         self.initWithUTF8String_(string.as_ptr())
     }
+
+    unsafe fn UTF8String(self) -> *const libc::c_char {
+        self.send_string("UTF8String", ())
+    }
 }
 
 pub trait NSView {
@@ -874,7 +894,9 @@ impl NSDate for id {
 
 pub trait NSEvent {
     unsafe fn get_type(self) -> NSEventType;
+    unsafe fn get_subtype(self) -> NSEventSubtype;
     unsafe fn locationInWindow(self) -> NSPoint;
+    unsafe fn characters(self) -> id;
 }
 
 impl NSEvent for id {
@@ -882,7 +904,15 @@ impl NSEvent for id {
         self.send_event("type", ())
     }
 
+    unsafe fn get_subtype(self) -> NSEventSubtype {
+        self.send_eventSubtype("subtype", ())
+    }
+
     unsafe fn locationInWindow(self) -> NSPoint {
         self.send_point("locationInWindow", ())
     }
+
+    unsafe fn characters(self) -> id {
+        self.send("characters", ())
+    }
 }
diff --git a/src/base.rs b/src/base.rs
index 965e128..47d1ef3 100644
--- a/src/base.rs
+++ b/src/base.rs
@@ -7,7 +7,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use appkit::{CGFloat, NSPoint, NSRect, NSSize, NSEventType};
+use appkit::{CGFloat, NSPoint, NSRect, NSSize, NSEventType, NSEventSubtype};
 use appkit::{NSWindowOrderingMode, NSAlignmentOptions};
 
 use libc::{c_double, c_long, c_ulong, c_char};
@@ -96,6 +96,8 @@ pub trait ObjCMethodCall {
     unsafe fn send_rect<S:ObjCSelector,A:ObjCMethodRectArgs>(self, selector: S, args: A) -> NSRect;
     unsafe fn send_size<S:ObjCSelector,A:ObjCMethodSizeArgs>(self, selector: S, args: A) -> NSSize;
     unsafe fn send_event<S:ObjCSelector,A:ObjCMethodEventArgs>(self, selector: S, args: A) -> NSEventType;
+    unsafe fn send_eventSubtype<S:ObjCSelector,A:ObjCMethodEventSubtypeArgs>(self, selector: S, args: A) -> NSEventSubtype;
+    unsafe fn send_string<S:ObjCSelector,A:ObjCMethodStringArgs>(self, selector: S, args: A) -> *const libc::c_char;
 }
 
 impl ObjCMethodCall for id {
@@ -150,6 +152,16 @@ impl ObjCMethodCall for id {
                         -> NSEventType {
         args.send_event_args(self, selector.as_selector())
     }
+    #[inline]
+    unsafe fn send_eventSubtype<S:ObjCSelector,A:ObjCMethodEventSubtypeArgs>(self, selector: S, args: A)
+                        -> NSEventSubtype {
+        args.send_eventSubtype_args(self, selector.as_selector())
+    }
+    #[inline]
+    unsafe fn send_string<S:ObjCSelector,A:ObjCMethodStringArgs>(self, selector: S, args: A)
+                        -> *const libc::c_char {
+        args.send_string_args(self, selector.as_selector())
+    }
 }
 
 /// A convenience implementation that allows methods on class names to be called directly, as in:
@@ -212,6 +224,16 @@ impl<'a> ObjCMethodCall for &'a str {
                         -> NSEventType {
         args.send_event_args(class(self), selector.as_selector())
     }
+    #[inline]
+    unsafe fn send_eventSubtype<S:ObjCSelector,A:ObjCMethodEventSubtypeArgs>(self, selector: S, args: A)
+                        -> NSEventSubtype {
+        args.send_eventSubtype_args(class(self), selector.as_selector())
+    }
+    #[inline]
+    unsafe fn send_string<S:ObjCSelector,A:ObjCMethodStringArgs>(self, selector: S, args: A)
+                        -> *const libc::c_char {
+        args.send_string_args(class(self), selector.as_selector())
+    }
 }
 
 /// A trait that allows C strings to be used as selectors without having to convert them first.
@@ -270,6 +292,14 @@ pub trait ObjCMethodEventArgs {
     unsafe fn send_event_args(self, receiver: id, selector: SEL) -> NSEventType;
 }
 
+pub trait ObjCMethodEventSubtypeArgs {
+    unsafe fn send_eventSubtype_args(self, receiver: id, selector: SEL) -> NSEventSubtype;
+}
+
+pub trait ObjCMethodStringArgs {
+    unsafe fn send_string_args(self, receiver: id, selector: SEL) -> *const libc::c_char;
+}
+
 impl ObjCMethodArgs for () {
     #[inline]
     unsafe fn send_args(self, receiver: id, selector: SEL) -> id {
@@ -457,6 +487,13 @@ impl ObjCMethodBoolArgs for () {
     }
 }
 
+impl ObjCMethodBoolArgs for () {
+    #[inline]
+    unsafe fn send_bool_args(self, receiver: id, selector: SEL) -> bool {
+        invoke_msg_bool(receiver, selector)
+    }
+}
+
 impl ObjCMethodBoolArgs for c_long {
     #[inline]
     unsafe fn send_bool_args(self, receiver: id, selector: SEL) -> bool {
@@ -535,6 +572,21 @@ impl ObjCMethodPointArgs for (NSPoint, id) {
         invoke_msg_NSPoint_NSPoint_id(receiver, selector, first, second)
     }
 }
+
+impl ObjCMethodEventSubtypeArgs for () {
+    #[inline]
+    unsafe fn send_eventSubtype_args(self, receiver: id, selector: SEL) -> NSEventSubtype {
+        invoke_msg_NSEventSubtype(receiver, selector)
+    }
+}
+
+impl ObjCMethodStringArgs for () {
+    #[inline]
+    unsafe fn send_string_args(self, receiver: id, selector: SEL) -> *const libc::c_char {
+        invoke_msg_string(receiver, selector)
+    }
+}
+
 /// A trait that simulates variadic parameters for method calls.
 
 #[cfg(test)]