Leap Motion Java API Reference  0.8.0
com.leapmotion.leap.ScreenTapGesture Class Reference

The ScreenTapGesture class represents a tapping gesture by a finger or tool. More...

Inherits com.leapmotion.leap.Gesture.

Public Member Functions

Vector direction ()
 The direction of finger tip motion.
 
Pointable pointable ()
 The finger performing the screen tap gesture.
 
Vector position ()
 The position where the screen tap is registered.
 
float progress ()
 The progess value is always 1.0 for a screen tap gesture.
 
 ScreenTapGesture ()
 Constructs a new ScreenTapGesture object.
 
 ScreenTapGesture (Gesture rhs)
 Constructs a ScreenTapGesture object from an instance of the Gesture class.
 
- Public Member Functions inherited from com.leapmotion.leap.Gesture
long duration ()
 The elapsed duration of the recognized movement up to the frame containing this Gesture object, in microseconds.
 
float durationSeconds ()
 The elapsed duration in seconds.
 
boolean equals (Gesture rhs)
 Compare Gesture object equality.
 
Frame frame ()
 The Frame containing this Gesture instance.
 
 Gesture ()
 Constructs a new Gesture object.
 
 Gesture (Gesture rhs)
 Constructs a new copy of an Gesture object.
 
HandList hands ()
 The list of hands associated with this Gesture, if any.
 
int id ()
 The gesture ID.
 
boolean isValid ()
 Reports whether this Gesture instance represents a valid Gesture.
 
PointableList pointables ()
 The list of fingers and tools associated with this Gesture, if any.
 
Gesture.State state ()
 The gesture state.
 
String toString ()
 A string containing a brief, human-readable description of this Gesture.
 
Gesture.Type type ()
 The gesture type.
 

Static Public Member Functions

static Gesture.Type classType ()
 The screen tap gesture type.
 
- Static Public Member Functions inherited from com.leapmotion.leap.Gesture
static Gesture invalid ()
 Returns an invalid Gesture object.
 

Detailed Description

The ScreenTapGesture class represents a tapping gesture by a finger or tool.

A screen tap gesture is recognized when the tip of a finger pokes forward and then springs back to approximately the original postion, as if tapping a vertical screen. The tapping finger must pause briefly before beginning the tap.

Leap_Gesture_Tap2.png

Important: To use screen tap gestures in your application, you must enable recognition of the screen tap gesture. You can enable recognition with:

controller.enableGesture(Gesture.Type.TYPE_SCREEN_TAP);

ScreenTap gestures are discrete. The ScreenTapGesture object representing a tap always has the state, STATE_STOP. Only one ScreenTapGesture object is created for each screen tap gesture recognized.

You can set the minimum finger movement and velocity required for a movement to be recognized as a screen tap as well as adjust the detection window for evaluating the movement using the config attribute of a connected Controller object. Use the following keys to configure screen tap recognition:

Key string Value type Default value Units
Gesture.ScreenTap.MinForwardVelocity float 50 mm/s
Gesture.ScreenTap.HistorySeconds float 0.1 s
Gesture.ScreenTap.MinDistance float 3.0 mm

The following example demonstrates how to set the screen tap configuration parameters:

if(controller.config().setFloat("Gesture.ScreenTap.MinForwardVelocity", 30.0f) &&
controller.config().setFloat("Gesture.ScreenTap.HistorySeconds", .5f) &&
controller.config().setFloat("Gesture.ScreenTap.MinDistance", 1.0f))
controller.config().save();

Constructor & Destructor Documentation

com.leapmotion.leap.ScreenTapGesture.ScreenTapGesture ( )

Constructs a new ScreenTapGesture object.

An uninitialized ScreenTapGesture object is considered invalid. Get valid instances of the ScreenTapGesture class from a Frame object.

com.leapmotion.leap.ScreenTapGesture.ScreenTapGesture ( Gesture  rhs)

Constructs a ScreenTapGesture object from an instance of the Gesture class.

Parameters
rhsThe Gesture instance to specialize. This Gesture instance must be a ScreenTapGesture object.

Member Function Documentation

static Gesture.Type com.leapmotion.leap.ScreenTapGesture.classType ( )
static

The screen tap gesture type.

Returns
Type The type value designating a screen tap gesture.
Vector com.leapmotion.leap.ScreenTapGesture.direction ( )

The direction of finger tip motion.

Returns
Vector A unit direction vector.
Pointable com.leapmotion.leap.ScreenTapGesture.pointable ( )

The finger performing the screen tap gesture.

Returns
Pointable A Pointable object representing the tapping finger.
Vector com.leapmotion.leap.ScreenTapGesture.position ( )

The position where the screen tap is registered.

Returns
Vector A Vector containing the coordinates of screen tap location.
float com.leapmotion.leap.ScreenTapGesture.progress ( )

The progess value is always 1.0 for a screen tap gesture.

Returns
float The value 1.0.