Module javafx.graphics
Package javafx.scene.input

# Class TouchPoint

java.lang.Object
javafx.scene.input.TouchPoint

All Implemented Interfaces:
  `Serializable`

    public final class TouchPoint
    extends Object
    implements Serializable

Touch point represents a single point of a multi-touch action, typically one finger touching a screen. It is contained in `TouchEvent`.

The touch point has its coordinates, state (see `TouchPoint.State`) and ID. The ID is sequential number of this touch point unique in scope of a single multi-touch gesture.

Each touch point is by default delivered to a single node during its whole trajectory - to the node on which it was pressed. There is a grabbing API to modify this behavior. The above means that when touch point is pressed, it is automatically grabbed by the top-most node on the press coordinates. Any time during the gesture `grab()` and `ungrab()` methods can be used to alter the event delivery target. When grabbed by a different node, it will next time be targeted to it; when ungrabbed, it will be always targeted to the top-most node on the current location.

Since:
  JavaFX 2.2
See Also:
  Serialized Form

- ## Nested Class Summary

  Nested Classes
  Modifier and Type | Class | Description
  --- | --- | ---
  `static class` | `TouchPoint.State` | Represents current state of the touch point

- ## Constructor Summary

  Constructors
  Constructor | Description
  --- | ---
  `TouchPoint​(int id, TouchPoint.State state, double x, double y, double screenX, double screenY, EventTarget target, PickResult pickResult)` | Creates new instance of TouchPoint.

- ## Method Summary

  Modifier and Type | Method | Description
  --- | --- | ---
  `boolean` | `belongsTo​(EventTarget target)` | Distinguishes between touch points targeted to the given node or some of its children from touch points targeted somewhere else.
  `EventTarget` | `getGrabbed()` | Gets event target which has grabbed this touch point.
  `int` | `getId()` | Gets identifier of this touch point.
  `PickResult` | `getPickResult()` | Returns information about the pick.
  `double` | `getSceneX()` | Gets the horizontal position of the touch point relative to the origin of the `Scene` that contains the TouchEvent's source.
  `double` | `getSceneY()` | Gets the vertical position of the touch point relative to the origin of the `Scene` that contains the TouchEvent's source.
  `double` | `getScreenX()` | Gets the absolute horizontal position of the touch point.
  `double` | `getScreenY()` | Gets the absolute vertical position of the touch point.
  `TouchPoint.State` | `getState()` | Gets state of this touch point
  `EventTarget` | `getTarget()` | Gets event target on which the touch event carrying this touch point is fired.
  `double` | `getX()` | Gets the horizontal position of the touch point relative to the origin of the TouchEvent's source.
  `double` | `getY()` | Gets the vertical position of the touch point relative to the origin of the TouchEvent's source.
  `double` | `getZ()` | Depth position of the event relative to the origin of the MouseEvent's source.
  `void` | `grab()` | Grabs this touch point by current event source.
  `void` | `grab​(EventTarget target)` | Grabs this touch point by the given target.
  `String` | `toString()` | Returns a string representation of this `TouchPoint` object.
  `void` | `ungrab()` | Ungrabs this touch point from its target.

  ### Methods inherited from class java.lang.Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

- ## Constructor Details

  - ### TouchPoint

    public TouchPoint​(int id, TouchPoint.State state, double x, double y, double screenX, double screenY, EventTarget target, PickResult pickResult)
    Creates new instance of TouchPoint.
    Parameters:
      `id` - ID of the new touch point
      `state` - state of the new touch point
      `x` - The x with respect to the scene.
      `y` - The y with respect to the scene.
      `screenX` - The x coordinate relative to screen.
      `screenY` - The y coordinate relative to screen.
      `target` - Node or other event target.
      `pickResult` - pick result. Can be null, in this case a 2D pick result without any further values is constructed based on the scene coordinates and target
    Since:
      JavaFX 8.0

- ## Method Details

  - ### belongsTo

    public boolean belongsTo​(EventTarget target)
    Distinguishes between touch points targeted to the given node or some of its children from touch points targeted somewhere else. This allows for testing all touch points carried by one touch event on their relevance for a given node.
    Parameters:
      `target` - Node or other event target to be tested
    Returns:
      true if this touch point is targeted to the given target or some of its children

  - ### getGrabbed

    public EventTarget getGrabbed()
    Gets event target which has grabbed this touch point.
    Returns:
      The current grabbed target, null if the touch point is ungrabbed

  - ### grab

    public void grab()
    Grabs this touch point by current event source. Next event containing this touch point will be targeted to the same node whose event handler called this method.

  - ### grab

    public void grab​(EventTarget target)
    Grabs this touch point by the given target. Next event containing this touch point will be targeted to it.
    Parameters:
      `target` - Target by which to grab the touch point

  - ### ungrab

    public void ungrab()
    Ungrabs this touch point from its target. Since the next event this touch point will be delivered to the top-most node picked on its respective location until it is grabbed again or released.

  - ### getId

    public final int getId()
    Gets identifier of this touch point. The number is sequential and unique in scope of one multi touch gesture. The first pressed touch point has id `1`, each subsequently pressed touch points gets the next ordinal number until all touch points are released and the counter is reset.
    Returns:
      the identifier of this touch point.

  - ### getState

    public final TouchPoint.State getState()
    Gets state of this touch point
    Returns:
      state of this touch point

  - ### getX

    public final double getX()
    Gets the horizontal position of the touch point relative to the origin of the TouchEvent's source.
    Returns:
      the horizontal position of the touch point relative to the origin of the TouchEvent's source.

  - ### getY

    public final double getY()
    Gets the vertical position of the touch point relative to the origin of the TouchEvent's source.
    Returns:
      the vertical position of the touch point relative to the origin of the TouchEvent's source.

  - ### getZ

    public final double getZ()
    Depth position of the event relative to the origin of the MouseEvent's source.
    Returns:
      depth position of the event relative to the origin of the MouseEvent's source.
    Since:
      JavaFX 8.0

  - ### getScreenX

    public final double getScreenX()
    Gets the absolute horizontal position of the touch point.
    Returns:
      the absolute horizontal position of the touch point

  - ### getScreenY

    public final double getScreenY()
    Gets the absolute vertical position of the touch point.
    Returns:
      the absolute vertical position of the touch point

  - ### getSceneX

    public final double getSceneX()
    Gets the horizontal position of the touch point relative to the origin of the `Scene` that contains the TouchEvent's source. If the node is not in a `Scene`, then the value is relative to the boundsInParent of the root-most parent of the TouchEvent's node. Note that in 3D scene, this represents the flat coordinates after applying the projection transformations.
    Returns:
      the horizontal position of the touch point relative to the origin of the `Scene` that contains the TouchEvent's source

  - ### getSceneY

    public final double getSceneY()
    Gets the vertical position of the touch point relative to the origin of the `Scene` that contains the TouchEvent's source. If the node is not in a `Scene`, then the value is relative to the boundsInParent of the root-most parent of the TouchEvent's node. Note that in 3D scene, this represents the flat coordinates after applying the projection transformations.
    Returns:
      the vertical position of the touch point relative to the origin of the `Scene` that contains the TouchEvent's source

  - ### getPickResult

    public final PickResult getPickResult()
    Returns information about the pick.
    Returns:
      new PickResult object that contains information about the pick
    Since:
      JavaFX 8.0

  - ### getTarget

    public EventTarget getTarget()
    Gets event target on which the touch event carrying this touch point is fired.
    Returns:
      Event target for this touch point

  - ### toString

    public String toString()
    Returns a string representation of this `TouchPoint` object.
    Overrides:
      `toString` in class `Object`
    Returns:
      a string representation of this `TouchPoint` object.