Download - UIResponder Class
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UIResponder Class Reference
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Contents
UIResponder Class Reference 4Overview 4
Tasks 5
Managing the Responder Chain 5
Managing Input Views 5
Responding to Touch Events 6
Responding to Motion Events 6
Responding to Remote-Control Events 6
Getting the Undo Manager 6
Validating Commands 6
Accessing the Available Key Commands 7
Managing the Text Input Mode 7
Properties 7
inputAccessoryView 7
inputView 8
keyCommands 8
textInputContextIdentifier 9
textInputMode 9
undoManager 10
Class Methods 10
clearTextInputContextIdentifier: 10
Instance Methods 11
becomeFirstResponder 11
canBecomeFirstResponder 11
canPerformAction:withSender: 12
canResignFirstResponder 13
isFirstResponder 14
motionBegan:withEvent: 14
motionCancelled:withEvent: 15
motionEnded:withEvent: 16
nextResponder 16
reloadInputViews 17
remoteControlReceivedWithEvent: 17
resignFirstResponder 18
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targetForAction:withSender: 19
touchesBegan:withEvent: 19
touchesCancelled:withEvent: 20
touchesEnded:withEvent: 21
touchesMoved:withEvent: 22
Document Revision History 24
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Contents
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Inherits from NSObject
Conforms to NSObject (NSObject)
Framework /System/Library/Frameworks/UIKit.framework
Availability Available in iOS 2.0 and later.
Companion guide Event Handling Guide for iOS
Declared in UIResponder.h
Related sample code Handling Touches Using Responder Methods and Gesture Recognizers
iAdSuite
Managed App Configuration
TableView Fundamentals for iOS
Using NSXMLParser to parse XML documents
OverviewThe UIResponder class defines an interface for objects that respond to and handle events. It is the superclass
of UIApplication, UIView and its subclasses (which include UIWindow). Instances of these classes are
sometimes referred to as responder objects or, simply, responders.
There are two general kinds of events: touch events and motion events. The primary event-handling methods
for touches are touchesBegan:withEvent: (page 19), touchesMoved:withEvent: (page 22),
touchesEnded:withEvent: (page 21), and touchesCancelled:withEvent: (page 20). The parameters of
these methods associate touches with their eventsespecially touches that are new or have changedand
thus allow responder objects to track and handle the touches as the delivered events progress through the
phases of a multi-touch sequence. Any time a finger touches the screen, is dragged on the screen, or lifts from
the screen, a UIEvent object is generated. The event object contains UITouch objects for all fingers on the
screen or just lifted from it.
2013-09-18 | Copyright 2013 Apple Inc. All Rights Reserved.
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UIResponder Class Reference
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iOS 3.0 introduced system capabilities for generating motion events, specifically the motion of shaking the
device. The event-handling methods for these kinds of events are motionBegan:withEvent: (page 14),
motionEnded:withEvent: (page 16), and motionCancelled:withEvent: (page 15). Additionally for iOS 3.0,
the canPerformAction:withSender: (page 12) method allows responders to validate commands in the user
interface while the undoManager (page 10) property returns the nearest NSUndoManager object in the responder
chain.
In iOS 4.0, UIResponder added the remoteControlReceivedWithEvent: (page 17) method for handling
remote-control events.
Tasks
Managing the Responder Chain
nextResponder (page 16)
Returns the receiver'snext responder, or nil if it has none.
isFirstResponder (page 14)
Returns a Boolean value indicating whether the receiver is the first responder.
canBecomeFirstResponder (page 11)
Returns a Boolean value indicating whether the receiver can become first responder.
becomeFirstResponder (page 11)
Notifies the receiver that it is about to become first responder in its window.
canResignFirstResponder (page 13)
Returns a Boolean value indicating whether the receiver is willing to relinquish first-responder status.
resignFirstResponder (page 18)
Notifies the receiver that it has been asked to relinquish its status as first responder in its window.
Managing Input Views
inputView (page 8) property
The custom input view to display when the object becomes the first responder. (read-only)
inputAccessoryView (page 7) property
The custom accessory view to display when the object becomes the first responder. (read-only)
reloadInputViews (page 17)
Updates the custom input and accessory views when the object is the first responder.
UIResponder Class ReferenceTasks
2013-09-18 | Copyright 2013 Apple Inc. All Rights Reserved.
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Responding to Touch Events
touchesBegan:withEvent: (page 19)
Tells the receiver when one or more fingers touch down in a view or window.
touchesMoved:withEvent: (page 22)
Tells the receiver when one or more fingers associated with an event move within a view or window.
touchesEnded:withEvent: (page 21)
Tells the receiver when one or more fingers are raised from a view or window.
touchesCancelled:withEvent: (page 20)
Sent to the receiver when a system event (such as a low-memory warning) cancels a touch event.
Responding to Motion Events
motionBegan:withEvent: (page 14)
Tells the receiver that a motion event has begun.
motionEnded:withEvent: (page 16)
Tells the receiver that a motion event has ended.
motionCancelled:withEvent: (page 15)
Tells the receiver that a motion event has been cancelled.
Responding to Remote-Control Events
remoteControlReceivedWithEvent: (page 17)
Sent to the receiver when a remote-control event is received.
Getting the Undo Manager
undoManager (page 10) property
Returns the nearest shared undo manager in the responder chain. (read-only)
Validating Commands
canPerformAction:withSender: (page 12)
Requests the receiving responder to enable or disable the specified command in the user interface.
UIResponder Class ReferenceTasks
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targetForAction:withSender: (page 19)
Returns the target object that responds to an action.
Accessing the Available Key Commands
keyCommands (page 8) property
The key commands that trigger actions on this responder. (read-only)
Managing the Text Input Mode
textInputMode (page 9) property
The text input mode for this responder object. (read-only)
textInputContextIdentifier (page 9) property
An identifier signifying that the responder should preserve its text input mode information. (read-only)
+ clearTextInputContextIdentifier: (page 10)
Clears text input mode information from the apps user defaults.
Properties
inputAccessoryView
The custom accessory view to display when the object becomes the first responder. (read-only)
@property(readonly, retain) UIView *inputAccessoryView
DiscussionThe default value of this property is nil. Subclasses that want to attach custom controls to either a
system-supplied input view (such as the keyboard) or a custom input view (one you provide in the
inputView (page 8) property) should redeclare this property as readwrite and use it to manage their custom
accessory view. When the receiver subsequently becomes the first responder, the responder infrastructure
attaches the view to the appropriate input view before displaying it.
This property is typically used to attach an accessory view to the system-supplied keyboard that is presented
for UITextField and UITextView objects.
AvailabilityAvailable in iOS 3.2 and later.
UIResponder Class ReferenceProperties
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Declared inUIResponder.h
inputView
The custom input view to display when the object becomes the first responder. (read-only)
@property(readonly, retain) UIView *inputView
DiscussionThe value of this property is nil. Responder objects that require a custom view to gather input from the user
should redeclare this property as readwrite and use it to manage their custom input view. When the receiver
subsequently becomes the first responder, the responder infrastructure presents the specified input view
automatically. Similarly, when the view resigns its first responder status, the responder infrastructure
automatically dismisses the specified view.
This property is typically used to replace the system-supplied keyboard that is presented for UITextField
and UITextView objects.
AvailabilityAvailable in iOS 3.2 and later.
Declared inUIResponder.h
keyCommands
The key commands that trigger actions on this responder. (read-only)
@property(nonatomic, readonly) NSArray *keyCommands
DiscussionA responder object that supports hardware keyboard commands can redefine this property and use it to return
an array of UIKeyCommand objects that it supports. Each key command object represents the keyboard
sequence to recognize and the action method of the responder to call in response.
The key commands you return from this method are applied to the entire responder chain. When an key
combination is pressed that matches a key command object, UIKit walks the responder chain looking for an
object that implements the corresponding action method. It calls that method on the first object it finds and
then stops processing the event.
UIResponder Class ReferenceProperties
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AvailabilityAvailable in iOS 7.0 and later.
Declared inUIResponder.h
textInputContextIdentifier
An identifier signifying that the responder should preserve its text input mode information. (read-only)
@property(readonly, retain) NSString *textInputContextIdentifier
DiscussionIf you redefine this property and return a string value, UIKit tracks the current text input mode for the responder.
While in tracking mode, any programmatic changes you make to the text input mode are remembered and
restored whenever the responder becomes active.
AvailabilityAvailable in iOS 7.0 and later.
Declared inUIResponder.h
textInputMode
The text input mode for this responder object. (read-only)
@property(readonly, retain) UITextInputMode *textInputMode
DiscussionThe text input mode identifies the language and keyboard displayed when this responder is active.
For responders, the system normally displays a keyboard that is based on the users language preferences. You
can redefine this property and use it to return a different text input mode in cases where you want a responder
to use a specific keyboard. The user can still change the keyboard while the responder is active, but switching
away to another responder and then back restores the keyboard you specified.
AvailabilityAvailable in iOS 7.0 and later.
See Also @property textInputContextIdentifier (page 9)
UIResponder Class ReferenceProperties
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Declared inUIResponder.h
undoManager
Returns the nearest shared undo manager in the responder chain. (read-only)
@property(nonatomic, readonly) NSUndoManager *undoManager
DiscussionBy default, every window of an application has an undo manager: a shared object for managing undo and
redo operations. However, the class of any object in the responder chain can have their own custom undo
manager. (For example, instances of UITextField have their own undo manager that is cleared when the
text field resigns first-responder status.) When you request an undo manager, the request goes up the responder
chain and the UIWindowobject returns a usable instance.
You may add undo managers to your view controllers to perform undo and redo operations local to the
managed view.
AvailabilityAvailable in iOS 3.0 and later.
Declared inUIResponder.h
Class Methods
clearTextInputContextIdentifier:
Clears text input mode information from the apps user defaults.
+ (void)clearTextInputContextIdentifier:(NSString *)identifier
Parametersidentifier
An identifier assigned to the textInputContextIdentifier (page 9) property of one of your responders.
DiscussionCalling this method removes any text input mode information associated with the specified identifier from
the apps user defaults. Removing this information causes the responder to use the default text input mode
again.
UIResponder Class ReferenceClass Methods
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AvailabilityAvailable in iOS 7.0 and later.
Declared inUIResponder.h
Instance Methods
becomeFirstResponder
Notifies the receiver that it is about to become first responder in its window.
- (BOOL)becomeFirstResponder
Return ValueYES if the receiver accepts first-responder status or NO if it refuses this status. The default implementation
returns YES, accepting first responder status.
DiscussionSubclasses can override this method to update state or perform some action such as highlighting the selection.
A responder object only becomes the first responder if the current responder can resign first-responder status
(canResignFirstResponder (page 13)) and the new responder can become first responder.
You may call this method to make a responder object such as a view the first responder. However, you should
only call it on that view if it is part of a view hierarchy. If the views window property holds a UIWindow object,
it has been installed in a view hierarchy; if it returns nil, the view is detached from any hierarchy.
AvailabilityAvailable in iOS 2.0 and later.
See Also isFirstResponder (page 14) canBecomeFirstResponder (page 11)
Declared inUIResponder.h
canBecomeFirstResponder
Returns a Boolean value indicating whether the receiver can become first responder.
UIResponder Class ReferenceInstance Methods
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- (BOOL)canBecomeFirstResponder
Return ValueYES if the receiver can become the first responder, NO otherwise.
DiscussionReturns NO by default. If a responder object returns YES from this method, it becomes the first responder and
can receive touch events and action messages. Subclasses must override this method to be able to become
first responder.
You must not send this message to a view that is not currently attached to the view hierarchy. The result is
undefined.
AvailabilityAvailable in iOS 2.0 and later.
See Also becomeFirstResponder (page 11)
Related Sample CodeAudio Mixer (MixerHost)Handling Touches Using Responder Methods and Gesture RecognizersMoviePlayer
Declared inUIResponder.h
canPerformAction:withSender:
Requests the receiving responder to enable or disable the specified command in the user interface.
- (BOOL)canPerformAction:(SEL)action withSender:(id)sender
Parametersaction
A selector that identifies a method associated with a command. For the editing menu, this is one of the
editing methods declared by the UIResponderStandardEditActions informal protocol (for example,
copy:).
sender
The object calling this method. For the editing menu commands, this is the shared UIApplication
object. Depending on the context, you can query the sender for information to help you determine
whether a command should be enabled.
UIResponder Class ReferenceInstance Methods
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Return ValueYES if the the command identified by action should be enabled or NO if it should be disabled. Returning YES
means that your class can handle the command in the current context.
DiscussionThis default implementation of this method returns YES if the responder class implements the requested action
and calls the next responder if it does not. Subclasses may override this method to enable menu commands
based on the current state; for example, you would enable the Copy command if there is a selection or disable
the Paste command if the pasteboard did not contain data with the correct pasteboard representation type.
If no responder in the responder chain returns YES, the menu command is disabled. Note that if your class
returns NO for a command, another responder further up the responder chain may still return YES, enabling
the command.
This method might be called more than once for the same action but with a different sender each time. You
should be prepared for any kind of sender including nil.
For information on the editing menu, see the description of the UIMenuController class.
AvailabilityAvailable in iOS 3.0 and later.
Declared inUIResponder.h
canResignFirstResponder
Returns a Boolean value indicating whether the receiver is willing to relinquish first-responder status.
- (BOOL)canResignFirstResponder
Return ValueYES if the receiver can resign first-responder status, NO otherwise.
DiscussionReturns YES by default. As an example, a text field in the middle of editing might want to implement this
method to return NO to keep itself active during editing.
AvailabilityAvailable in iOS 2.0 and later.
See Also resignFirstResponder (page 18)
UIResponder Class ReferenceInstance Methods
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Declared inUIResponder.h
isFirstResponder
Returns a Boolean value indicating whether the receiver is the first responder.
- (BOOL)isFirstResponder
Return ValueYES if the receiver is the first responder, NO otherwise.
AvailabilityAvailable in iOS 2.0 and later.
See Also becomeFirstResponder (page 11) resignFirstResponder (page 18)
Related Sample CodeEADemoGeocoderDemo
Declared inUIResponder.h
motionBegan:withEvent:
Tells the receiver that a motion event has begun.
- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event
Parametersmotion
An event-subtype constant indicating the kind of motion. A common motion is shaking, which is indicated
by UIEventSubtypeMotionShake.
event
An object representing the event associated with the motion.
DiscussioniOS informs the first responder only when a motion event starts and when it ends; for example, it doesnt report
individual shakes. The receiving object must be the first responder to receive motion events.
UIResponder Class ReferenceInstance Methods
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The default implementation of this method does nothing. However immediate UIKit subclasses of UIResponder,
particularly UIView, forward the message up the responder chain.
AvailabilityAvailable in iOS 3.0 and later.
See Also motionEnded:withEvent: (page 16) motionCancelled:withEvent: (page 15)
Declared inUIResponder.h
motionCancelled:withEvent:
Tells the receiver that a motion event has been cancelled.
- (void)motionCancelled:(UIEventSubtype)motion withEvent:(UIEvent *)event
Parametersmotion
An event-subtype constant indicating the kind of motion associated with event. A common motion is
shaking, which is indicated by UIEventSubtypeMotionShake.
event
An object representing the event associated with the motion.
DiscussionThis method is invoked when the Cocoa Touch framework receives an interruption requiring cancellation of
the motion event. This interruption is something that might cause the application to be no longer active or
the view to be removed from the window. The method can also be invoked if the shaking goes on too long.
All responders that handle motion events should implement this method; in it they should clean up any state
information that was established in the motionBegan:withEvent: (page 14) implementation.
The default implementation of this method does nothing. However immediate UIKit subclasses of UIResponder,
particularly UIView, forward the message up the responder chain.
AvailabilityAvailable in iOS 3.0 and later.
See Also motionBegan:withEvent: (page 14) motionEnded:withEvent: (page 16)
UIResponder Class ReferenceInstance Methods
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Declared inUIResponder.h
motionEnded:withEvent:
Tells the receiver that a motion event has ended.
- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event
Parametersmotion
An event-subtype constant indicating the kind of motion. A common motion is shaking, which is indicated
by UIEventSubtypeMotionShake.
event
An object representing the event associated with the motion.
DiscussioniOS informs the responder only when a motion event starts and when it ends; for example, it doesnt report
individual shakes.
The default implementation of this method does nothing. However immediate UIKit subclasses of UIResponder,
particularly UIView, forward the message up the responder chain.
AvailabilityAvailable in iOS 3.0 and later.
See Also motionBegan:withEvent: (page 14) motionCancelled:withEvent: (page 15)
Declared inUIResponder.h
nextResponder
Returns the receiver'snext responder, or nil if it has none.
- (UIResponder *)nextResponder
Return ValueThe next object in the responder chain to be presented with an event for handling.
UIResponder Class ReferenceInstance Methods
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DiscussionThe UIResponder class does not store or set the next responder automatically, instead returning nil by
default. Subclasses must override this method to set the next responder. UIView implements this method by
returning the UIViewController object that manages it (if it has one) or its superview (if it doesnt);
UIViewController implements the method by returning its views superview; UIWindow returns the
application object, and UIApplication returns nil.
AvailabilityAvailable in iOS 2.0 and later.
See Also isFirstResponder (page 14)
Declared inUIResponder.h
reloadInputViews
Updates the custom input and accessory views when the object is the first responder.
- (void)reloadInputViews
DiscussionYou can use this method to refresh the custom input view or input accessory view associated with the current
object when it is the first responder. The views are replaced immediatelythat is, without animating them
into place. If the current object is not the first responder, this method has no effect.
AvailabilityAvailable in iOS 3.2 and later.
Declared inUIResponder.h
remoteControlReceivedWithEvent:
Sent to the receiver when a remote-control event is received.
- (void)remoteControlReceivedWithEvent:(UIEvent *)event
UIResponder Class ReferenceInstance Methods
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Parametersevent
An event object encapsulating a remote-control command. Remote-control events have a type of
UIEventTypeRemoteControl.
DiscussionRemote-control events originate as commands from external accessories, including headsets. An application
responds to these commands by controlling audio or video media presented to the user. The receiving responder
object should examine the subtype of event to determine the intended commandfor example, play
(UIEventSubtypeRemoteControlPlay)and then proceed accordingly.
To allow delivery of remote-control events, you must call the beginReceivingRemoteControlEvents
method of UIApplication; to turn off delivery of remote-control events, call
endReceivingRemoteControlEvents.
AvailabilityAvailable in iOS 4.0 and later.
Declared inUIResponder.h
resignFirstResponder
Notifies the receiver that it has been asked to relinquish its status as first responder in its window.
- (BOOL)resignFirstResponder
DiscussionThe default implementation returns YES, resigning first responder status. Subclasses can override this method
to update state or perform some action such as unhighlighting the selection, or to return NO, refusing to
relinquish first responder status. If you override this method, you must call super (the superclass
implementation) at some point in your code.
AvailabilityAvailable in iOS 2.0 and later.
See Also isFirstResponder (page 14) canResignFirstResponder (page 13)
Related Sample CodeAdvancedURLConnectionsAirDrop Examples
UIResponder Class ReferenceInstance Methods
2013-09-18 | Copyright 2013 Apple Inc. All Rights Reserved.
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EADemoSimple Core Data RelationshipsUICatalog
Declared inUIResponder.h
targetForAction:withSender:
Returns the target object that responds to an action.
- (id)targetForAction:(SEL)action withSender:(id)sender
Parametersaction
A selector that identifies a method associated with a command.
sender
The object calling this method. For the editing menu commands, this is the shared UIApplication
object. Depending on the context, you can query the sender for information to help you determine the
target of the command.
Return ValueThe object whose action method is invoked to execute the command.
DiscussionThis method is called whenever an action needs to be invoked by the object. The default implementation calls
the canPerformAction:withSender: (page 12) method to determine whether it can invoke the action. If the
object can invoke the action, it returns itself, otherwise it passes the request up the responder chain. Your app
should override this method if it wants to override how a target is selected.
AvailabilityAvailable in iOS 7.0 and later.
Declared inUIResponder.h
touchesBegan:withEvent:
Tells the receiver when one or more fingers touch down in a view or window.
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
UIResponder Class ReferenceInstance Methods
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Parameterstouches
A set of UITouch instances that represent the touches for the starting phase of the event represented
by event.
event
An object representing the event to which the touches belong.
DiscussionThe default implementation of this method does nothing. However immediate UIKit subclasses of UIResponder,
particularly UIView, forward the message up the responder chain. To forward the message to the next responder,
send the message to super (the superclass implementation); do not send the message directly to the next
responder. For example,
[super touchesBegan:touches withEvent:event];
If you override this method without calling super (a common use pattern), you must also override the other
methods for handling touch events, if only as stub (empty) implementations.
Multiple touches are disabled by default. In order to receive multiple touch events you must set the a
multipleTouchEnabled property of the corresponding view instance to YES.
AvailabilityAvailable in iOS 2.0 and later.
See Also touchesMoved:withEvent: (page 22) touchesEnded:withEvent: (page 21) touchesCancelled:withEvent: (page 20)
Declared inUIResponder.h
touchesCancelled:withEvent:
Sent to the receiver when a system event (such as a low-memory warning) cancels a touch event.
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
UIResponder Class ReferenceInstance Methods
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Parameterstouches
A set of UITouch instances that represent the touches for the ending phase of the event represented
by event.
event
An object representing the event to which the touches belong.
DiscussionThis method is invoked when the Cocoa Touch framework receives a system interruption requiring cancellation
of the touch event; for this, it generates a UITouch object with a phase of UITouchPhaseCancel. The
interruption is something that might cause the application to be no longer active or the view to be removed
from the window
When an object receives a touchesCancelled:withEvent:message it should clean up any state information
that was established in its touchesBegan:withEvent: (page 19) implementation.
The default implementation of this method does nothing. However immediate UIKit subclasses of UIResponder,
particularly UIView, forward the message up the responder chain. To forward the message to the next responder,
send the message to super (the superclass implementation); do not send the message directly to the next
responder. For example,
[super touchesCancelled:touches withEvent:event];
If you override this method without calling super (a common use pattern), you must also override the other
methods for handling touch events, if only as stub (empty) implementations.
AvailabilityAvailable in iOS 2.0 and later.
See Also touchesBegan:withEvent: (page 19) touchesMoved:withEvent: (page 22) motionEnded:withEvent: (page 16)
Declared inUIResponder.h
touchesEnded:withEvent:
Tells the receiver when one or more fingers are raised from a view or window.
UIResponder Class ReferenceInstance Methods
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- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
Parameterstouches
A set of UITouch instances that represent the touches for the ending phase of the event represented
by event.
event
An object representing the event to which the touches belong.
DiscussionThe default implementation of this method does nothing. However immediate UIKit subclasses of UIResponder,
particularly UIView, forward the message up the responder chain. To forward the message to the next responder,
send the message to super (the superclass implementation); do not send the message directly to the next
responder. For example,
[super touchesEnded:touches withEvent:event];
When an object receives a touchesEnded:withEvent: message it should clean up any state information
that was established in its touchesBegan:withEvent: (page 19) implementation.
Multiple touches are disabled by default. In order to receive multiple touch events you must set the a
multipleTouchEnabled property of the corresponding view instance to YES.
If you override this method without calling super (a common use pattern), you must also override the other
methods for handling touch events, if only as stub (empty) implementations.
AvailabilityAvailable in iOS 2.0 and later.
See Also touchesBegan:withEvent: (page 19) touchesMoved:withEvent: (page 22) touchesCancelled:withEvent: (page 20)
Declared inUIResponder.h
touchesMoved:withEvent:
Tells the receiver when one or more fingers associated with an event move within a view or window.
UIResponder Class ReferenceInstance Methods
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- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
Parameterstouches
A set of UITouch instances that represent the touches that are moving during the event represented by
event.
event
An object representing the event to which the touches belong.
DiscussionThe default implementation of this method does nothing. However immediate UIKit subclasses of UIResponder,
particularly UIView, forward the message up the responder chain. To forward the message to the next responder,
send the message to super (the superclass implementation); do not send the message directly to the next
responder. For example,
[super touchesMoved:touches withEvent:event];
Multiple touches are disabled by default. In order to receive multiple touch events you must set the a
multipleTouchEnabled property of the corresponding view instance to YES.
If you override this method without calling super (a common use pattern), you must also override the other
methods for handling touch events, if only as stub (empty) implementations.
AvailabilityAvailable in iOS 2.0 and later.
See Also touchesBegan:withEvent: (page 19) touchesEnded:withEvent: (page 21) touchesCancelled:withEvent: (page 20)
Declared inUIResponder.h
UIResponder Class ReferenceInstance Methods
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This table describes the changes to UIResponder Class Reference .
NotesDate
Added new APIs introduced in iOS 7.2013-09-18
Added caveats about calling super for the touch-handling methods and
for resignFirstResponder.
2011-03-07
Improved description of default behavior of touch- and motion-event
handling methods.
2010-08-03
Added a description of the remoteControlReceivedWithEvent: method
(iOS 4.0).
2010-04-15
Updated for iOS 3.2.2010-02-25
Made minor corrections.2009-05-27
Added descriptions of the methods added for iOS 3.0: undoManager,
canPerformAction:withSender:, and the motion-handling methods.
2009-03-08
New document describing the class that defines an interface for objects
responding to and handling events.
2008-06-26
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Document Revision History
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UIResponder Class ReferenceContentsUIResponder Class ReferenceOverviewTasksManaging the Responder ChainManaging Input ViewsResponding to Touch EventsResponding to Motion EventsResponding to Remote-Control EventsGetting the Undo ManagerValidating CommandsAccessing the Available Key CommandsManaging the Text Input Mode
PropertiesinputAccessoryViewinputViewkeyCommandstextInputContextIdentifiertextInputModeundoManager
Class MethodsclearTextInputContextIdentifier:
Instance MethodsbecomeFirstRespondercanBecomeFirstRespondercanPerformAction:withSender:canResignFirstResponderisFirstRespondermotionBegan:withEvent:motionCancelled:withEvent:motionEnded:withEvent:nextResponderreloadInputViewsremoteControlReceivedWithEvent:resignFirstRespondertargetForAction:withSender:touchesBegan:withEvent:touchesCancelled:withEvent:touchesEnded:withEvent:touchesMoved:withEvent:
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