MotionPredictor

Kotlin |Java

public final class MotionPredictor
extends Object

java.lang.Object
↳	android.view.MotionPredictor

Calculate motion predictions. Feed motion events to this class in order to generate predicted future events. The prediction functionality may not be available on all devices: check if a specific source is supported on a given input device using isPredictionAvailable(int, int). Send all of the events that were received from the system to record(MotionEvent) to generate complete, accurate predictions from predict(long). When processing the returned predictions, make sure to consider all of the historical samples.

Summary

Public constructors
`MotionPredictor(Context context)` Create a new MotionPredictor for the provided `Context`.

Public methods
`boolean`	`isPredictionAvailable(int deviceId, int source)` Check whether a device supports motion predictions for a given source type.
`MotionEvent`	`predict(long predictionTimeNanos)` Get a predicted event for the gesture that has been provided to `record(MotionEvent)`.
`void`	`record(MotionEvent event)` Record a movement so that in the future, a prediction for the current gesture can be generated.

Inherited methods

From class


        
          java.lang.Object

`Object`	`clone()` Creates and returns a copy of this object.
`boolean`	`equals(Object obj)` Indicates whether some other object is "equal to" this one.
`void`	`finalize()` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
`final Class<?>`	`getClass()` Returns the runtime class of this `Object`.
`int`	`hashCode()` Returns a hash code value for the object.
`final void`	`notify()` Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()` Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()` Returns a string representation of the object.
`final void`	`wait(long timeoutMillis, int nanos)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait()` Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

Public constructors

MotionPredictor

Added in API level 34

public MotionPredictor (Context context)

Create a new MotionPredictor for the provided Context.

Parameters
`context`	`Context`: The context for the predictions. This value cannot be `null`.

Public methods

isPredictionAvailable

Added in API level 34

public boolean isPredictionAvailable (int deviceId, 
                int source)

Check whether a device supports motion predictions for a given source type.

Parameters
`deviceId`	`int`: The input device id.
`source`	`int`: The source of input events.

Returns
`boolean`	True if the current device supports predictions, false otherwise.

See also:

predict

Added in API level 34

public MotionEvent predict (long predictionTimeNanos)

Get a predicted event for the gesture that has been provided to record(MotionEvent). Predictions may not reach the requested timestamp if the confidence in the prediction results is low.

Parameters
`predictionTimeNanos`	`long`: The time that the prediction should target, in the `SystemClock.uptimeMillis()` time base, but in nanoseconds.

Returns
`MotionEvent`	The predicted motion event, or `null` if predictions are not supported, or not possible for the current gesture. Be sure to check the historical data in addition to the latest (`getX()`, `getY()`) coordinates for smooth prediction curves.

record

Added in API level 34

public void record (MotionEvent event)

Record a movement so that in the future, a prediction for the current gesture can be generated. Only gestures from one input device at a time should be provided to an instance of MotionPredictor.

Parameters
`event`	`MotionEvent`: The received event. This value cannot be `null`.

Throws
`IllegalArgumentException`	if an inconsistent MotionEvent stream is sent.