Moves all key command implementation back to SLKTextView, introducing…

… a totally new approach for better key input observation using completion blocks. This finally fixes a strange retain cycle caused by interacting with key commands in SLKTextViewController.
slackhq · Feb 13, 2016 · 5c27485 · 5c27485
1 parent 80281f6
commit 5c27485
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Showing 5 changed files with 100 additions and 110 deletions.
diff --git a/Examples/Messenger-Shared/MessageViewController.m b/Examples/Messenger-Shared/MessageViewController.m
@@ -183,8 +183,7 @@ - (void)configureActionItems
                                                                target:self
                                                                action:@selector(togglePIPWindow:)];
 
-    self.navigationItem.leftBarButtonItems = @[arrowItem];
-    self.navigationItem.rightBarButtonItems = @[pipItem, editItem, appendItem, typeItem];
+    self.navigationItem.rightBarButtonItems = @[arrowItem, pipItem, editItem, appendItem, typeItem];
 }
 
 
@@ -425,13 +424,14 @@ - (void)didPressRightButton:(id)sender
 
 - (void)didPressArrowKey:(id)sender
 {
-    [super didPressArrowKey:sender];
-
     UIKeyCommand *keyCommand = (UIKeyCommand *)sender;
 
-    if ([keyCommand.input isEqualToString:UIKeyInputUpArrow]) {
+    if ([keyCommand.input isEqualToString:UIKeyInputUpArrow] && self.textView.text.length == 0) {
         [self editLastMessage:nil];
     }
+    else {
+        [super didPressArrowKey:sender];
+    }
 }
 
 - (NSString *)keyForTextCaching

diff --git a/Source/SLKTextInputbar.m b/Source/SLKTextInputbar.m
@@ -719,7 +719,7 @@ - (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(N
 }
 
 
-#pragma mark - NSNotificationCenter register/unregister
+#pragma mark - NSNotificationCenter registration
 
 - (void)slk_registerNotifications
 {

diff --git a/Source/SLKTextView.h b/Source/SLKTextView.h
@@ -99,7 +99,7 @@ typedef NS_OPTIONS(NSUInteger, SLKPastableMediaType) {
 /**
  Notifies the text view that the user pressed any arrow key. This is used to move the cursor up and down while having multiple lines.
  */
-- (void)didPressAnyArrowKey:(id)sender;
+- (void)didPressAnyArrowKey:(UIKeyCommand *)keyCommand;
 
 
 #pragma mark - Markdown Formatting
@@ -121,6 +121,20 @@ typedef NS_OPTIONS(NSUInteger, SLKPastableMediaType) {
  */
 - (void)registerMarkdownFormattingSymbol:(NSString *)symbol withTitle:(NSString *)title;
 
+
+#pragma mark - External Keyboard Support
+
+/**
+ Registers and observes key commands' updates, when the text view is first responder.
+ Instead of typically overriding UIResponder's -keyCommands method, it is better to use this API for easier and safer implementation of key input detection.
+ 
+ @param input The keys that must be pressed by the user. Required.
+ @param modifiers The bit mask of modifier keys that must be pressed. Use 0 if none.
+ @param title The title to display to the user. Optional.
+ @param completion A completion block called whenever the key combination is detected. Required.
+ */
+- (void)observeKeyInput:(NSString *)input modifiers:(UIKeyModifierFlags)modifiers title:(NSString *)title completion:(void (^)(UIKeyCommand *keyCommand))completion;
+
 @end
 
 

diff --git a/Source/SLKTextView.m b/Source/SLKTextView.m
@@ -40,9 +40,6 @@ @interface SLKTextView ()
 // The initial font point size, used for dynamic type calculations
 @property (nonatomic) CGFloat initialFontSize;
 
-// The keyboard commands available for external keyboards
-@property (nonatomic, strong) NSArray *keyboardCommands;
-
 // Used for moving the caret up/down
 @property (nonatomic) UITextLayoutDirection verticalMoveDirection;
 @property (nonatomic) CGRect verticalMoveStartCaretRect;
@@ -55,6 +52,10 @@ @interface SLKTextView ()
 @property (nonatomic, strong) NSMutableArray *registeredFormattingSymbols;
 @property (nonatomic, getter=isFormatting) BOOL formatting;
 
+// The keyboard commands available for external keyboards
+@property (nonatomic, strong) NSMutableDictionary *registeredKeyCommands;
+@property (nonatomic, strong) NSMutableDictionary *registeredKeyCallbacks;
+
 @end
 
 @implementation SLKTextView
@@ -227,7 +228,7 @@ - (BOOL)isTypingSuggestionEnabled
 
 - (BOOL)isFormattingEnabled
 {
-    return (_registeredFormattingSymbols.count > 0) ? YES : NO;
+    return (self.registeredFormattingSymbols.count > 0) ? YES : NO;
 }
 
 // Returns only a supported pasted item
@@ -916,68 +917,70 @@ - (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event
 
 #pragma mark - External Keyboard Support
 
-- (NSArray *)keyCommands
+typedef void (^SLKKeyCommandHandler)(UIKeyCommand *keyCommand);
+
+- (void)observeKeyInput:(NSString *)input modifiers:(UIKeyModifierFlags)modifiers title:(NSString *)title completion:(SLKKeyCommandHandler)completion;
 {
-    if (_keyboardCommands) {
-        return _keyboardCommands;
+    NSAssert([input isKindOfClass:[NSString class]], @"You must provide a string with one or more characters corresponding to the keys to observe.");
+    NSAssert(completion != nil, @"You must provide a non-nil completion block.");
+
+    if (!input || !completion) {
+        return;
     }
 
-    _keyboardCommands = @[
-         // Return
-         [UIKeyCommand keyCommandWithInput:@"\r" modifierFlags:UIKeyModifierShift action:@selector(slk_didPressLineBreakKeys:)],
-         [UIKeyCommand keyCommandWithInput:@"\r" modifierFlags:UIKeyModifierAlternate action:@selector(slk_didPressLineBreakKeys:)],
-         [UIKeyCommand keyCommandWithInput:@"\r" modifierFlags:UIKeyModifierControl action:@selector(slk_didPressLineBreakKeys:)],
-
-         // Undo/Redo
-         [UIKeyCommand keyCommandWithInput:@"z" modifierFlags:UIKeyModifierCommand action:@selector(slk_didPressCommandZKeys:)],
-         [UIKeyCommand keyCommandWithInput:@"z" modifierFlags:UIKeyModifierShift|UIKeyModifierCommand action:@selector(slk_didPressCommandZKeys:)],
-         ];
+    UIKeyCommand *keyCommand = [UIKeyCommand keyCommandWithInput:input modifierFlags:modifiers action:@selector(didDetectKeyCommand:)];
 
-    return _keyboardCommands;
+#ifdef __IPHONE_9_0
+    if ([UIKeyCommand respondsToSelector:@selector(keyCommandWithInput:modifierFlags:action:discoverabilityTitle:)] ) {
+        keyCommand.discoverabilityTitle = title;
+    }
+#endif
+
+    if (!_registeredKeyCommands) {
+        _registeredKeyCommands = [NSMutableDictionary new];
+        _registeredKeyCallbacks = [NSMutableDictionary new];
+    }
+
+    NSString *key = [self keyForKeyCommand:keyCommand];
+
+    self.registeredKeyCommands[key] = keyCommand;
+    self.registeredKeyCallbacks[key] = completion;
 }
 
-
-#pragma mark Line Break
-
-- (void)slk_didPressLineBreakKeys:(id)sender
+- (void)didDetectKeyCommand:(UIKeyCommand *)keyCommand
 {
-    [self slk_insertNewLineBreak];
+    NSString *key = [self keyForKeyCommand:keyCommand];
+
+    SLKKeyCommandHandler completion = self.registeredKeyCallbacks[key];
+
+    if (completion) {
+        completion(keyCommand);
+    }
 }
 
+- (NSString *)keyForKeyCommand:(UIKeyCommand *)keyCommand
+{
+    return [NSString stringWithFormat:@"%@_%ld", keyCommand.input, (long)keyCommand.modifierFlags];
+}
 
-#pragma mark Undo/Redo Text
-
-- (void)slk_didPressCommandZKeys:(id)sender
+- (NSArray *)keyCommands
 {
-    if (!self.undoManagerEnabled) {
-        return;
+    if (self.registeredKeyCommands) {
+        return [self.registeredKeyCommands allValues];
     }
 
-    UIKeyCommand *keyCommand = (UIKeyCommand *)sender;
-
-    if ((keyCommand.modifierFlags & UIKeyModifierShift) > 0) {
-
-        if ([self.undoManager canRedo]) {
-            [self.undoManager redo];
-        }
-    }
-    else {
-        if ([self.undoManager canUndo]) {
-            [self.undoManager undo];
-        }
-    }
+    return nil;
 }
 
+
 #pragma mark Up/Down Cursor Movement
 
-- (void)didPressAnyArrowKey:(id)sender
+- (void)didPressAnyArrowKey:(UIKeyCommand *)keyCommand
 {
-    if (self.text.length == 0 || self.numberOfLines < 2) {
+    if (![keyCommand isKindOfClass:[UIKeyCommand class]] || self.text.length == 0 || self.numberOfLines < 2) {
         return;
     }
 
-    UIKeyCommand *keyCommand = (UIKeyCommand *)sender;
-
     if ([keyCommand.input isEqualToString:UIKeyInputUpArrow]) {
         [self slk_moveCursorTodirection:UITextLayoutDirectionUp];
     }
@@ -1070,7 +1073,7 @@ - (BOOL)slk_isNewVerticalMovementForPosition:(UITextPosition *)position inDirect
 }
 
 
-#pragma mark - NSNotificationCenter register/unregister
+#pragma mark - NSNotificationCenter registration
 
 - (void)slk_registerNotifications
 {
@@ -1104,6 +1107,11 @@ - (void)dealloc
     [self removeObserver:self forKeyPath:NSStringFromSelector(@selector(contentSize))];
 
     _placeholderLabel = nil;
+
+    _registeredFormattingTitles = nil;
+    _registeredFormattingSymbols = nil;
+    _registeredKeyCommands = nil;
+    _registeredKeyCallbacks = nil;
 }
 
 @end
diff --git a/Source/SLKTextViewController.m b/Source/SLKTextViewController.m
@@ -62,9 +62,6 @@ @interface SLKTextViewController ()
 // YES if the view controller's view's size is changing by its parent (i.e. when its window rotates or is resized)
 @property (nonatomic, getter = isTransitioning) BOOL transitioning;
 
-// The keyboard commands available for external keyboards
-@property (nonatomic, strong) NSArray *keyboardCommands;
-
 // Optional classes to be used instead of the default ones.
 @property (nonatomic, strong) Class textViewClass;
 @property (nonatomic, strong) Class typingIndicatorViewClass;
@@ -187,6 +184,8 @@ - (void)viewDidLoad
     [self.view addSubview:self.textInputbar];
 
     [self slk_setupViewConstraints];
+
+    [self slk_registerKeyCommands];
 }
 
 - (void)viewWillAppear:(BOOL)animated
@@ -2202,72 +2201,41 @@ - (void)slk_updateViewConstraints
 }
 
 
-#pragma mark - External Keyboard Support
+#pragma mark - Keyboard Command registration
 
-- (NSArray *)keyCommands
+- (void)slk_registerKeyCommands
 {
-    if (_keyboardCommands) {
-        return _keyboardCommands;
-    }
-
-    _keyboardCommands = @[[self slk_returnKeyCommand],
-                          [self slk_escKeyCommand],
-                          [self slk_arrowKeyCommand:UIKeyInputUpArrow],
-                          [self slk_arrowKeyCommand:UIKeyInputDownArrow],
-                          ];
-
-    return _keyboardCommands;
-}
+    __weak typeof(self) weakSelf = self;
 
-- (UIKeyCommand *)slk_returnKeyCommand
-{
-    UIKeyCommand *command = [UIKeyCommand keyCommandWithInput:@"\r" modifierFlags:0 action:@selector(didPressReturnKey:)];
-
-#ifdef __IPHONE_9_0
-    if ([UIKeyCommand respondsToSelector:@selector(keyCommandWithInput:modifierFlags:action:discoverabilityTitle:)] ) {
-        // Only available since iOS 9
-        command.discoverabilityTitle = [self.rightButton titleForState:UIControlStateNormal] ? : NSLocalizedString(@"Send/Accept", nil);
-    }
-#endif
+    // Enter Key
+    [self.textView observeKeyInput:@"\r" modifiers:0 title:NSLocalizedString(@"Send/Accept", nil) completion:^(UIKeyCommand *keyCommand) {
+        [weakSelf didPressReturnKey:keyCommand];
+    }];
 
-    return command;
-}
-
-- (UIKeyCommand *)slk_escKeyCommand
-{
-    UIKeyCommand *command = [UIKeyCommand keyCommandWithInput:UIKeyInputEscape modifierFlags:0 action:@selector(didPressEscapeKey:)];
+    // Esc Key
+    [self.textView observeKeyInput:UIKeyInputEscape modifiers:0 title:NSLocalizedString(@"Dismiss", nil) completion:^(UIKeyCommand *keyCommand) {
+        [weakSelf didPressEscapeKey:keyCommand];
+    }];
 
-#ifdef __IPHONE_9_0
-    if ([UIKeyCommand respondsToSelector:@selector(keyCommandWithInput:modifierFlags:action:discoverabilityTitle:)] ) {
-        // Only available since iOS 9
-        command.discoverabilityTitle = NSLocalizedString(@"Dismiss", nil);
-    }
-#endif
+    // Up Arrow
+    [self.textView observeKeyInput:UIKeyInputUpArrow modifiers:0 title:nil completion:^(UIKeyCommand *keyCommand) {
+        [weakSelf didPressArrowKey:keyCommand];
+    }];
 
-    return command;
+    // Down Arrow
+    [self.textView observeKeyInput:UIKeyInputDownArrow modifiers:0 title:nil completion:^(UIKeyCommand *keyCommand) {
+        [weakSelf didPressArrowKey:keyCommand];
+    }];
 }
 
-- (UIKeyCommand *)slk_arrowKeyCommand:(NSString *)inputUpArrow
+- (NSArray *)keyCommands
 {
-    UIKeyCommand *command = [UIKeyCommand keyCommandWithInput:inputUpArrow modifierFlags:0 action:@selector(didPressArrowKey:)];
-
-#ifdef __IPHONE_9_0
-    // Only available since iOS 9
-    if ([UIKeyCommand respondsToSelector:@selector(keyCommandWithInput:modifierFlags:action:discoverabilityTitle:)] ) {
-        if ([inputUpArrow isEqualToString:UIKeyInputUpArrow]) {
-            command.discoverabilityTitle = NSLocalizedString(@"Move Up", nil);
-        }
-        if ([inputUpArrow isEqualToString:UIKeyInputDownArrow]) {
-            command.discoverabilityTitle = NSLocalizedString(@"Move Down", nil);
-        }
-    }
-#endif
-
-    return command;
+    // Important to keep this in, for backwards compatibility.
+    return @[];
 }
 
 
-#pragma mark - NSNotificationCenter register/unregister
+#pragma mark - NSNotificationCenter registration
 
 - (void)slk_registerNotifications
 {
-Original file line number
+Diff line change
@@ Expand Up @@
     }
-    #pragma mark - NSNotificationCenter register/unregister
+    #pragma mark - NSNotificationCenter registration
     - (void)slk_registerNotifications
     {
@@ Expand Down @@