UIFieldBehavior Class

Reference

Definition

Namespace:: UIKit

Assembly:: Xamarin.iOS.dll

Important

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A UIDynamicBehavior that models a field, such as gravity, electricity, or turbulence.

[Foundation.Register("UIFieldBehavior", true)]
[ObjCRuntime.Introduced(ObjCRuntime.PlatformName.iOS, 9, 0, ObjCRuntime.PlatformArchitecture.All, null)]
public class UIFieldBehavior : UIKit.UIDynamicBehavior

type UIFieldBehavior = class
    inherit UIDynamicBehavior

Inheritance: Object

NSObject

UIDynamicBehavior
UIFieldBehavior

Attributes: RegisterAttribute IntroducedAttribute

Remarks

UIFieldBehavior objects apply a force vector to one or more IUIDynamicItem objects (such as UIView objects). The vector depends on the type of field generated, as shown in the following:

A UIFieldBehavior only applies to the IUIDynamicItem objects in its Items array. The following example creates a vortex field centered in the main screen. The field applies to each of the items in the wanderers array of UIView objects. Once the UIFieldBehavior is created and applied to the UIDynamicItemBehavior objects associated with the views in wanderers, the behavior is added to the UIDynamicAnimator.

let fieldBehavior = UIFieldBehavior.CreateVortexField()
fieldBehavior.Position <- new CGPoint(this.View.Frame.Left + this.View.Frame.Width / nfloat 2.0, this.View.Frame.Top + this.View.Frame.Height / nfloat 2.0)
fieldBehavior.MinimumRadius <- nfloat 5.0

let animator = new UIDynamicAnimator(this.View)

let wanderers = 
    seq { 20.0 .. 60.0 .. (Math.Floor(float frame.Height)) }
    |> Seq.map (fun y -> new CGRect(20.0, y, 20.0, 20.0))
    |> Seq.map (fun frame -> 
        let v = new UIView(frame)
        v.BackgroundColor <- UIColor.Red
        v
        ) |> Array.ofSeq
this.View.AddSubviews(wanderers)

wanderers 
|> Seq.map (fun w -> new UIDynamicItemBehavior([| w :> IUIDynamicItem|])) 
|> Seq.iter (fun itemBehavior ->
    itemBehavior.Density <- nfloat 0.01
    itemBehavior.Resistance <- nfloat 0.0
    itemBehavior.Friction <- nfloat 0.0
    itemBehavior.AllowsRotation <- true
    itemBehavior.Charge <- nfloat -1.0
    animator.AddBehavior(itemBehavior)
    )

wanderers |> Seq.iter fieldBehavior.AddItem

animator.AddBehavior(fieldBehavior)

The vortex force vectors are shown here:

Developers may visualize the field with PerformSelector(new ObjCRuntime.Selector("setDebugEnabled:"), Foundation.NSObject.FromObject(true)).

Constructors

UIFieldBehavior(IntPtr)	A constructor used when creating managed representations of unmanaged objects; Called by the runtime.
UIFieldBehavior(NSObjectFlag)	Constructor to call on derived classes to skip initialization and merely allocate the object.

Properties

Action	The NSAction that executes during dynamic animation. (Inherited from UIDynamicBehavior)
AnimationSpeed	In noise and turbulence fields, the multiplier for animation.
ChildBehaviors	The children UIDynamicBehaviors of this UIDynamicBehavior. Read-only. (Inherited from UIDynamicBehavior)
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)
Direction	The direction of motion in linear and gravity fields.
DynamicAnimator	The UIDynamicAnimator associated with this UIDynamicBehavior. Read-only. (Inherited from UIDynamicBehavior)
Falloff	The rate of field diminishment at distances greater than MinimumRadius.
Handle	Handle (pointer) to the unmanaged object representation. (Inherited from NSObject)
IsDirectBinding	(Inherited from NSObject)
IsProxy	(Inherited from NSObject)
Items	The set of IUIDynamicItem objects to which this field applies.
MinimumRadius	Objects closer than this distance are calculated as if they were at this minimum distance.
Position	The location of the center of the field, in view coordinates.
Region	This, with Position, determines the limits of the field's effects.
RetainCount	Returns the current Objective-C retain count for the object. (Inherited from NSObject)
Self	(Inherited from NSObject)
Smoothness	In noise or turbulence fields, the amount of noise or turbulence, in the range 0 (maximum) to 1 (minimum).
Strength	The strength of the field, in arbitrary units that differ among fields
Superclass	(Inherited from NSObject)
SuperHandle	Handle used to represent the methods in the base class for this NSObject. (Inherited from NSObject)
Zone	(Inherited from NSObject)

Methods

AddChildBehavior(UIDynamicBehavior)	Adds a UIDynamicBehavior to this UIDynamicBehavior's ChildBehaviors. (Inherited from UIDynamicBehavior)
AddItem(IUIDynamicItem)	Adds the `item` to this UIFieldBehavior.
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)
CreateCustomField(UIFieldCustomEvaluator)	Creates a custom field defined by `evaluator`.
CreateDragField()	Factory method to create a field that mimics drag.
CreateElectricField()	Factory method to create a field that mimics an EM field interacting with Charge.
CreateLinearGravityField(CGVector)	Factory method to create a field that mimics gravity pulling in a single direction.
CreateMagneticField()	Factory method to create a field that mimics gravity pulling in a single direction.
CreateNoiseField(nfloat, nfloat)	Factory method to create a field with random forces.
CreateRadialGravityField(CGPoint)	Factory method to create a field that attracts objects to a point.
CreateSpringField()	Factory method to create a field that acts like a spring.
CreateTurbulenceField(nfloat, nfloat)	Factory method to create a field that simulates turbulence.
CreateVelocityField(CGVector)	Factory method to create a field that applies a linear velocity to affected items.
CreateVortexField()	Factory method to create a spiraling field.
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)
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)
Init()	(Inherited from NSObject)
InitializeHandle(IntPtr, String)	(Inherited from NSObject)
InitializeHandle(IntPtr)	(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)
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, NSObject, Double, NSString[])	(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, NSObject)	(Inherited from NSObject)
PerformSelector(Selector, NSObject)	(Inherited from NSObject)
PerformSelector(Selector, NSThread, NSObject, Boolean, NSString[])	(Inherited from NSObject)
PerformSelector(Selector, NSThread, NSObject, Boolean)	(Inherited from NSObject)
PerformSelector(Selector)	(Inherited from NSObject)
PrepareForInterfaceBuilder()	(Inherited from NSObject)
RemoveChildBehavior(UIDynamicBehavior)	Removes a UIDynamicBehavior from this UIDynamicBehavior's ChildBehaviors. (Inherited from UIDynamicBehavior)
RemoveItem(IUIDynamicItem)	Removes `item` from Items.
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, NSString)	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)
RemoveObserver(NSObject, String)	Stops the specified observer from receiving further notifications of changed values for the specified keyPath. (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)
WillMoveToAnimator(UIDynamicAnimator)	Indicates that this UIDynamicBehavior has been added or removed from a UIDynamicAnimator. (Inherited from UIDynamicBehavior)

Extension Methods

GetDebugDescription(INSObjectProtocol)
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

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