Fixed Cmd-R shortcut on iOS 9

Author: nicklockwood

React/Base/RCTKeyCommands.m

@@ -11,8 +11,16 @@
 
 #import <UIKit/UIKit.h>
 
+#import "RCTDefines.h"
 #import "RCTUtils.h"
 
+#if RCT_DEV
+
+static BOOL RCTIsIOS8OrEarlier()
+{
+  return [UIDevice currentDevice].systemVersion.floatValue < 9;
+}
+
 @interface RCTKeyCommand : NSObject <NSCopying>
 
 @property (nonatomic, strong) UIKeyCommand *keyCommand;
@@ -27,7 +35,7 @@ - (instancetype)initWithKeyCommand:(UIKeyCommand *)keyCommand
 {
   if ((self = [super init])) {
     _keyCommand = keyCommand;
-    _block = block ?: ^(__unused UIKeyCommand *cmd) {};
+    _block = block;
   }
   return self;
 }
@@ -58,29 +66,58 @@ - (BOOL)matchesInput:(NSString *)input flags:(UIKeyModifierFlags)flags
   return [_keyCommand.input isEqual:input] && _keyCommand.modifierFlags == flags;
 }
 
+- (NSString *)description
+{
+  return [NSString stringWithFormat:@"<%@:%p input=\"%@\" flags=%zd hasBlock=%@>",
+          [self class], self, _keyCommand.input, _keyCommand.modifierFlags,
+          _block ? @"YES" : @"NO"];
+}
+
 @end
 
 @interface RCTKeyCommands ()
 
 @property (nonatomic, strong) NSMutableSet *commands;
 
-- (BOOL)RCT_handleKeyCommand:(UIKeyCommand *)key;
-
 @end
 
-@implementation UIApplication (RCTKeyCommands)
+@implementation UIResponder (RCTKeyCommands)
 
 - (NSArray *)RCT_keyCommands
 {
   NSSet *commands = [RCTKeyCommands sharedInstance].commands;
-  return [[self RCT_keyCommands] arrayByAddingObjectsFromArray:
-          [[commands valueForKeyPath:@"keyCommand"] allObjects]];
+  return [[commands valueForKeyPath:@"keyCommand"] allObjects];
+}
+
+- (void)RCT_handleKeyCommand:(UIKeyCommand *)key
+{
+  // NOTE: throttle the key handler because on iOS 9 the handleKeyCommand:
+  // method gets called repeatedly if the command key is held down.
+
+  static NSTimeInterval lastCommand = 0;
+  if (RCTIsIOS8OrEarlier() || CACurrentMediaTime() - lastCommand > 0.5) {
+    for (RCTKeyCommand *command in [RCTKeyCommands sharedInstance].commands) {
+      if ([command.keyCommand.input isEqualToString:key.input] &&
+          command.keyCommand.modifierFlags == key.modifierFlags) {
+        if (command.block) {
+          command.block(key);
+          lastCommand = CACurrentMediaTime();
+        }
+      }
+    }
+  }
 }
 
+@end
+
+@implementation UIApplication (RCTKeyCommands)
+
+// Required for iOS 8.x
 - (BOOL)RCT_sendAction:(SEL)action to:(id)target from:(id)sender forEvent:(UIEvent *)event
 {
   if (action == @selector(RCT_handleKeyCommand:)) {
-    return [[RCTKeyCommands sharedInstance] RCT_handleKeyCommand:sender];
+    [self RCT_handleKeyCommand:sender];
+    return YES;
   }
   return [self RCT_sendAction:action to:target from:sender forEvent:event];
 }
@@ -91,9 +128,23 @@ @implementation RCTKeyCommands
 
 + (void)initialize
 {
-  //swizzle UIApplication
-  RCTSwapInstanceMethods([UIApplication class], @selector(keyCommands), @selector(RCT_keyCommands));
-  RCTSwapInstanceMethods([UIApplication class], @selector(sendAction:to:from:forEvent:), @selector(RCT_sendAction:to:from:forEvent:));
+  if (RCTIsIOS8OrEarlier()) {
+
+    //swizzle UIApplication
+    RCTSwapInstanceMethods([UIApplication class],
+                           @selector(keyCommands),
+                           @selector(RCT_keyCommands));
+
+    RCTSwapInstanceMethods([UIApplication class],
+                           @selector(sendAction:to:from:forEvent:),
+                           @selector(RCT_sendAction:to:from:forEvent:));
+  } else {
+
+    //swizzle UIResponder
+    RCTSwapInstanceMethods([UIResponder class],
+                           @selector(keyCommands),
+                           @selector(RCT_keyCommands));
+  }
 }
 
 + (instancetype)sharedInstance
@@ -121,11 +172,11 @@ - (void)registerKeyCommandWithInput:(NSString *)input
 {
   RCTAssertMainThread();
 
-  if (input.length && flags) {
+  if (input.length && flags && RCTIsIOS8OrEarlier()) {
 
     // Workaround around the first cmd not working: http://openradar.appspot.com/19613391
     // You can register just the cmd key and do nothing. This ensures that
-    // command-key modified commands will work first time.
+    // command-key modified commands will work first time. Fixed in iOS 9.
 
     [self registerKeyCommandWithInput:@""
                         modifierFlags:flags
@@ -136,19 +187,9 @@ - (void)registerKeyCommandWithInput:(NSString *)input
                                               modifierFlags:flags
                                                      action:@selector(RCT_handleKeyCommand:)];
 
-  [_commands addObject:[[RCTKeyCommand alloc] initWithKeyCommand:command block:block]];
-}
-
-- (BOOL)RCT_handleKeyCommand:(UIKeyCommand *)key
-{
-  for (RCTKeyCommand *command in [RCTKeyCommands sharedInstance].commands) {
-    if ([command.keyCommand.input isEqualToString:key.input] &&
-        command.keyCommand.modifierFlags == key.modifierFlags) {
-      command.block(key);
-      return YES;
-    }
-  }
-  return NO;
+  RCTKeyCommand *keyCommand = [[RCTKeyCommand alloc] initWithKeyCommand:command block:block];
+  [_commands removeObject:keyCommand];
+  [_commands addObject:keyCommand];
 }
 
 - (void)unregisterKeyCommandWithInput:(NSString *)input
@@ -178,3 +219,29 @@ - (BOOL)isKeyCommandRegisteredForInput:(NSString *)input
 }
 
 @end
+
+#else
+
+@implementation RCTKeyCommands
+
++ (instancetype)sharedInstance
+{
+  return nil;
+}
+
+- (void)registerKeyCommandWithInput:(NSString *)input
+                      modifierFlags:(UIKeyModifierFlags)flags
+                             action:(void (^)(UIKeyCommand *))block {}
+
+- (void)unregisterKeyCommandWithInput:(NSString *)input
+                        modifierFlags:(UIKeyModifierFlags)flags {}
+
+- (BOOL)isKeyCommandRegisteredForInput:(NSString *)input
+                         modifierFlags:(UIKeyModifierFlags)flags
+{
+  return NO;
+}
+
+@end
+
+#endif