UITouch Class

Reference

Definition

Namespace:: UIKit

Assembly:: Xamarin.iOS.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Represents a touch event on the screen.

[Foundation.Register("UITouch", true)]
public class UITouch : Foundation.NSObject

type UITouch = class
    inherit NSObject

Inheritance: Object

NSObject
UITouch

Attributes: RegisterAttribute

Remarks

This object encapsulates a touch or a finger movement on the screen.

The UITouch event is typically available from the NSSet passed to the Touch methods and also from the UIEvent instance that is passed to those methods.

TouchesBegan(NSSet, UIEvent): sent when one or more fingers touch the screen. :
TouchesMoved(NSSet, UIEvent): sent when one or more fingers move. :
TouchesEnded(NSSet, UIEvent): sent when one or more fingers are lifted from the screen. :
TouchesCancelled(NSSet, UIEvent): sent when the touch is cancelled by the system (for example if the phone interrupts your application). :

UIViews by default only handle a single touch event at once. If you want your view to handle multiple touches, you must set the MultipleTouchEnabled to true.

iOS creates a UIEvent object any time a finger touches the screen, moves or is removed from the screen. The UIEvent encapsulates all of the touches that are taking place on the screen at this point, even those that do not belong to this view. In addition to the UIEvent, there is an NSSet containing UITouch objects that represent the state of each finger on the screen for this particular view.

Constructors

UITouch()	Default constructor that initializes a new instance of this class with no parameters.
UITouch(IntPtr)	A constructor used when creating managed representations of unmanaged objects; Called by the runtime.
UITouch(NSObjectFlag)	Constructor to call on derived classes to skip initialization and merely allocate the object.

Properties

AltitudeAngle	The altitude, in radians, above horizontal, of the stylus.
Class	(Inherited from NSObject)
ClassHandle	The handle for this class.
DebugDescription	A developer-meaningful description of this object. (Inherited from NSObject)
Description	Description of the object, the Objective-C version of ToString. (Inherited from NSObject)
EstimatedProperties	The set of properties that may vary over the course of a touch.
EstimatedPropertiesExpectingUpdates	The set of properties that are likely to vary over the course of a touch.
EstimationUpdateIndex	If not `null`, a monotonically-increasing index into UITouch objects that have EstimatedProperties.
Force	Gets the force of the touch, where `1.0` represents the system-defined average force.
GestureRecognizers	The UIGestureRecognizers that are receiving this UITouch.
Handle	Handle (pointer) to the unmanaged object representation. (Inherited from NSObject)
IsDirectBinding	(Inherited from NSObject)
IsProxy	(Inherited from NSObject)
MajorRadius	The radius of the touch, governed by the MajorRadiusTolerance setting.
MajorRadiusTolerance	Provides the tolerance for the MajorRadius property. The actual radius is measured by MajorRadius±MajorRadiusTolerance.
MaximumPossibleForce	Gets the maximum force value that the system will recognize.
Phase	The UITouchPhase of this UITouch.
RetainCount	Returns the current Objective-C retain count for the object. (Inherited from NSObject)
Self	(Inherited from NSObject)
Superclass	(Inherited from NSObject)
SuperHandle	Handle used to represent the methods in the base class for this NSObject. (Inherited from NSObject)
TapCount	The number of taps associated with this UITouch. Read-only.
Timestamp	The time when this UITouch was created or last mutated. Read-only.
Type	The UITouchType of the UITouch.
View	The UIView in which this UITouch occurred. Read-only.
Window	The UIWindow in which this UITouch occurred. Read-only.
Zone	(Inherited from NSObject)

Methods

AddObserver(NSObject, NSString, NSKeyValueObservingOptions, IntPtr)	Registers an object for being observed externally (using NSString keyPath). Observed changes are dispatched to the observer’s object ObserveValue(NSString, NSObject, NSDictionary, IntPtr) method. (Inherited from NSObject)
AddObserver(NSObject, String, NSKeyValueObservingOptions, IntPtr)	Registers an object for being observed externally (using string keyPath). Observed changes are dispatched to the observer’s object ObserveValue(NSString, NSObject, NSDictionary, IntPtr) method. (Inherited from NSObject)
AddObserver(NSString, NSKeyValueObservingOptions, Action<NSObservedChange>)	Registers an object for being observed externally using an arbitrary method. (Inherited from NSObject)
AddObserver(String, NSKeyValueObservingOptions, Action<NSObservedChange>)	Registers an object for being observed externally using an arbitrary method. (Inherited from NSObject)
AwakeFromNib()	Called after the object has been loaded from the nib file. Overriders must call base.AwakeFromNib(). (Inherited from NSObject)
BeginInvokeOnMainThread(Action)	(Inherited from NSObject)
BeginInvokeOnMainThread(Selector, NSObject)	Invokes asynchrously the specified code on the main UI thread. (Inherited from NSObject)
Bind(NSString, NSObject, String, NSDictionary)	(Inherited from NSObject)
Bind(String, NSObject, String, NSDictionary)	Obsolete. (Inherited from NSObject)
BindingInfo(String)	Obsolete. (Inherited from NSObject)
BindingOptionDescriptions(String)	Obsolete. (Inherited from NSObject)
BindingValueClass(String)	Obsolete. (Inherited from NSObject)
CommitEditing()	(Inherited from NSObject)
CommitEditing(NSObject, Selector, IntPtr)	(Inherited from NSObject)
ConformsToProtocol(IntPtr)	Invoked to determine if this object implements the specified protocol. (Inherited from NSObject)
Copy()	Performs a copy of the underlying Objective-C object. (Inherited from NSObject)
DangerousAutorelease()	(Inherited from NSObject)
DangerousRelease()	(Inherited from NSObject)
DangerousRetain()	(Inherited from NSObject)
DidChange(NSKeyValueChange, NSIndexSet, NSString)	Indicates a change occurred to the indexes for a to-many relationship. (Inherited from NSObject)
DidChange(NSString, NSKeyValueSetMutationKind, NSSet)	(Inherited from NSObject)
DidChangeValue(String)	Indicates that a change occurred on the specified key. (Inherited from NSObject)
Dispose()	Releases the resources used by the NSObject object. (Inherited from NSObject)
Dispose(Boolean)	Releases the resources used by the NSObject object. (Inherited from NSObject)
DoesNotRecognizeSelector(Selector)	Indicates that this object does not recognize the specified selector. (Inherited from NSObject)
Equals(NSObject)	(Inherited from NSObject)
Equals(Object)	(Inherited from NSObject)
ExposedBindings()	(Inherited from NSObject)
GetAzimuthAngle(UIView)	Returns the rotation of the stylus relative to the plane of the screen, in radians.
GetAzimuthUnitVector(UIView)	Returns the rotation of the pointing device relative to the plane of the screen, as a unit vector.
GetBindingInfo(NSString)	(Inherited from NSObject)
GetBindingOptionDescriptions(NSString)	(Inherited from NSObject)
GetBindingValueClass(NSString)	(Inherited from NSObject)
GetDictionaryOfValuesFromKeys(NSString[])	Retrieves the values of the specified keys. (Inherited from NSObject)
GetHashCode()	Generates a hash code for the current instance. (Inherited from NSObject)
GetMethodForSelector(Selector)	(Inherited from NSObject)
GetNativeField(String)	Obsolete. (Inherited from NSObject)
GetNativeHash()	(Inherited from NSObject)
GetPreciseLocation(UIView)	Returns a precise location for the UITouch.
GetPrecisePreviousLocation(UIView)	Returns the UITouch object's previous precise location.
Init()	(Inherited from NSObject)
InitializeHandle(IntPtr)	(Inherited from NSObject)
InitializeHandle(IntPtr, String)	(Inherited from NSObject)
Invoke(Action, Double)	(Inherited from NSObject)
Invoke(Action, TimeSpan)	(Inherited from NSObject)
InvokeOnMainThread(Action)	(Inherited from NSObject)
InvokeOnMainThread(Selector, NSObject)	Invokes synchrously the specified code on the main UI thread. (Inherited from NSObject)
IsEqual(NSObject)	(Inherited from NSObject)
IsKindOfClass(Class)	(Inherited from NSObject)
IsMemberOfClass(Class)	(Inherited from NSObject)
LocationInView(UIView)	The location of this UITouch, in the coordinate system of the specified UIView.
MarkDirty()	Promotes a regular peer object (IsDirectBinding is true) into a toggleref object. (Inherited from NSObject)
MutableCopy()	Creates a mutable copy of the specified NSObject. (Inherited from NSObject)
ObjectDidEndEditing(NSObject)	(Inherited from NSObject)
ObserveValue(NSString, NSObject, NSDictionary, IntPtr)	Indicates that the value at the specified keyPath relative to this object has changed. (Inherited from NSObject)
PerformSelector(Selector)	(Inherited from NSObject)
PerformSelector(Selector, NSObject)	(Inherited from NSObject)
PerformSelector(Selector, NSObject, Double)	Invokes the selector on the current instance and if the `obj` is not null, it passes this as its single parameter. (Inherited from NSObject)
PerformSelector(Selector, NSObject, Double, NSString[])	(Inherited from NSObject)
PerformSelector(Selector, NSObject, NSObject)	(Inherited from NSObject)
PerformSelector(Selector, NSThread, NSObject, Boolean)	(Inherited from NSObject)
PerformSelector(Selector, NSThread, NSObject, Boolean, NSString[])	(Inherited from NSObject)
PrepareForInterfaceBuilder()	(Inherited from NSObject)
PreviousLocationInView(UIView)	The previous location of this UITouch, in the coordinate system of the specified UIView.
RemoveObserver(NSObject, NSString)	Stops the specified observer from receiving further notifications of changed values for the specified keyPath. (Inherited from NSObject)
RemoveObserver(NSObject, NSString, IntPtr)	Stops the specified observer from receiving further notifications of changed values for the specified keyPath and context. (Inherited from NSObject)
RemoveObserver(NSObject, String)	Stops the specified observer from receiving further notifications of changed values for the specified keyPath. (Inherited from NSObject)
RemoveObserver(NSObject, String, IntPtr)	Stops the specified observer from receiving further notifications of changed values for the specified keyPath and context. (Inherited from NSObject)
RespondsToSelector(Selector)	Whether this object recognizes the specified selector. (Inherited from NSObject)
SetNativeField(String, NSObject)	Obsolete. (Inherited from NSObject)
SetNilValueForKey(NSString)	Sets the value of the specified key to null. (Inherited from NSObject)
SetValueForKey(NSObject, NSString)	Sets the value of the property specified by the key to the specified value. (Inherited from NSObject)
SetValueForKeyPath(IntPtr, NSString)	A constructor used when creating managed representations of unmanaged objects; Called by the runtime. (Inherited from NSObject)
SetValueForKeyPath(NSObject, NSString)	Sets the value of a property that can be reached using a keypath. (Inherited from NSObject)
SetValueForUndefinedKey(NSObject, NSString)	Indicates an attempt to write a value to an undefined key. If not overridden, raises an NSUndefinedKeyException. (Inherited from NSObject)
SetValuesForKeysWithDictionary(NSDictionary)	Sets the values of this NSObject to those in the specified dictionary. (Inherited from NSObject)
ToString()	Returns a string representation of the value of the current instance. (Inherited from NSObject)
Unbind(NSString)	(Inherited from NSObject)
Unbind(String)	Obsolete. (Inherited from NSObject)
ValueForKey(NSString)	Returns the value of the property associated with the specified key. (Inherited from NSObject)
ValueForKeyPath(NSString)	Returns the value of a property that can be reached using a keypath. (Inherited from NSObject)
ValueForUndefinedKey(NSString)	Indicates an attempt to read a value of an undefined key. If not overridden, raises an NSUndefinedKeyException. (Inherited from NSObject)
WillChange(NSKeyValueChange, NSIndexSet, NSString)	Indicates that the values of the specified indices in the specified key are about to change. (Inherited from NSObject)
WillChange(NSString, NSKeyValueSetMutationKind, NSSet)	(Inherited from NSObject)
WillChangeValue(String)	Indicates that the value of the specified key is about to change. (Inherited from NSObject)

Extension Methods

GetDebugDescription(INSObjectProtocol)
LocationInNode(UITouch, SKNode)	The current position of `this` in the coordinate system of `node`.
PreviousLocationInNode(UITouch, SKNode)	The previous location of `this` in the coordinate system of `node`.
GetAccessibilityCustomRotors(NSObject)	Gets the array of UIAccessibilityCustomRotor objects appropriate for `this` object.
SetAccessibilityCustomRotors(NSObject, UIAccessibilityCustomRotor[])	Sets the array of UIAccessibilityCustomRotor objects appropriate for `this` object.

Applies to

通过