Added in API level 1

Summary: Nested Classes | Ctors | Methods | Inherited Methods

GestureDetector

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Kotlin |Java

public class GestureDetector
extends Object

java.lang.Object
↳	android.view.GestureDetector

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Detects various gestures and events using the supplied MotionEvents. The OnGestureListener callback will notify users when a particular motion event has occurred. This class should only be used with MotionEvents reported via touch (don't use for trackball events). To use this class:

• Create an instance of the GestureDetector for your View
• In the View#onTouchEvent(MotionEvent) method ensure you call onTouchEvent(android.view.MotionEvent). The methods defined in your callback will be executed when the events occur.
• If listening for OnContextClickListener#onContextClick(MotionEvent) you must call onGenericMotionEvent(android.view.MotionEvent) in View#onGenericMotionEvent(MotionEvent).

Summary

Nested classes
interface	GestureDetector.OnContextClickListener The listener that is used to notify when a context click occurs.
interface	GestureDetector.OnDoubleTapListener The listener that is used to notify when a double-tap or a confirmed single-tap occur.
interface	GestureDetector.OnGestureListener The listener that is used to notify when gestures occur.
class	GestureDetector.SimpleOnGestureListener A convenience class to extend when you only want to listen for a subset of all the gestures.

Public constructors
GestureDetector(GestureDetector.OnGestureListener listener, Handler handler) This constructor is deprecated. Use GestureDetector(android.content.Context, android.view.GestureDetector.OnGestureListener, android.os.Handler) instead.
GestureDetector(GestureDetector.OnGestureListener listener) This constructor is deprecated. Use GestureDetector(android.content.Context, android.view.GestureDetector.OnGestureListener) instead.
GestureDetector(Context context, GestureDetector.OnGestureListener listener) Creates a GestureDetector with the supplied listener.
GestureDetector(Context context, GestureDetector.OnGestureListener listener, Handler handler) Creates a GestureDetector with the supplied listener that runs deferred events on the thread associated with the supplied Handler.
GestureDetector(Context context, GestureDetector.OnGestureListener listener, Handler handler, boolean unused) Creates a GestureDetector with the supplied listener that runs deferred events on the thread associated with the supplied Handler.

Public methods
boolean	isLongpressEnabled()
boolean	onGenericMotionEvent(MotionEvent ev) Analyzes the given generic motion event and if applicable triggers the appropriate callbacks on the OnGestureListener supplied.
boolean	onTouchEvent(MotionEvent ev) Analyzes the given motion event and if applicable triggers the appropriate callbacks on the OnGestureListener supplied.
void	setContextClickListener(GestureDetector.OnContextClickListener onContextClickListener) Sets the listener which will be called for context clicks.
void	setIsLongpressEnabled(boolean isLongpressEnabled) Set whether longpress is enabled, if this is enabled when a user presses and holds down you get a longpress event and nothing further.
void	setOnDoubleTapListener(GestureDetector.OnDoubleTapListener onDoubleTapListener) Sets the listener which will be called for double-tap and related gestures.

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

GestureDetector

Added in API level 1

public GestureDetector (GestureDetector.OnGestureListener listener, 
                Handler handler)

This constructor is deprecated.
Use GestureDetector(android.content.Context, android.view.GestureDetector.OnGestureListener, android.os.Handler) instead.

Creates a GestureDetector with the supplied listener. This variant of the constructor should be used from a non-UI thread (as it allows specifying the Handler).

Parameters
listener	GestureDetector.OnGestureListener: the listener invoked for all the callbacks, this must not be null.
handler	Handler: the handler to use This value may be null.

Throws
NullPointerException	if listener is null.

GestureDetector

Added in API level 1

public GestureDetector (GestureDetector.OnGestureListener listener)

This constructor is deprecated.
Use GestureDetector(android.content.Context, android.view.GestureDetector.OnGestureListener) instead.

Creates a GestureDetector with the supplied listener. You may only use this constructor from a UI thread (this is the usual situation).

Parameters
listener	GestureDetector.OnGestureListener: the listener invoked for all the callbacks, this must not be null.

Throws
NullPointerException	if listener is null.

See also:

• Handler.Handler()

GestureDetector

Added in API level 3

public GestureDetector (Context context, 
                GestureDetector.OnGestureListener listener)

Creates a GestureDetector with the supplied listener. You may only use this constructor from a Looper thread.

Parameters
context	Context: An Activity or a Context created from Context#createWindowContext(int, Bundle) This value may be null.
listener	GestureDetector.OnGestureListener: the listener invoked for all the callbacks, this must not be null. If the listener implements the OnDoubleTapListener or OnContextClickListener then it will also be set as the listener for these callbacks (for example when using the SimpleOnGestureListener).

Throws
NullPointerException	if listener is null.

See also:

• Handler.Handler()

GestureDetector

Added in API level 3

public GestureDetector (Context context, 
                GestureDetector.OnGestureListener listener, 
                Handler handler)

Creates a GestureDetector with the supplied listener that runs deferred events on the thread associated with the supplied Handler.

Parameters
context	Context: An Activity or a Context created from Context#createWindowContext(int, Bundle) This value may be null.
listener	GestureDetector.OnGestureListener: the listener invoked for all the callbacks, this must not be null. If the listener implements the OnDoubleTapListener or OnContextClickListener then it will also be set as the listener for these callbacks (for example when using the SimpleOnGestureListener).
handler	Handler: the handler to use for running deferred listener events. This value may be null.

Throws
NullPointerException	if listener is null.

See also:

• Handler.Handler()

GestureDetector

Added in API level 8

public GestureDetector (Context context, 
                GestureDetector.OnGestureListener listener, 
                Handler handler, 
                boolean unused)

Creates a GestureDetector with the supplied listener that runs deferred events on the thread associated with the supplied Handler.

Parameters
context	Context: An Activity or a Context created from Context#createWindowContext(int, Bundle) This value may be null.
listener	GestureDetector.OnGestureListener: the listener invoked for all the callbacks, this must not be null.
handler	Handler: the handler to use for running deferred listener events. This value may be null.
unused	boolean: currently not used.

Throws
NullPointerException	if listener is null.

See also:

• Handler.Handler()

Public methods

isLongpressEnabled

Added in API level 1

public boolean isLongpressEnabled ()

Returns
boolean	true if longpress is enabled, else false.

onGenericMotionEvent

Added in API level 23

public boolean onGenericMotionEvent (MotionEvent ev)

Analyzes the given generic motion event and if applicable triggers the appropriate callbacks on the OnGestureListener supplied.

Parameters
ev	MotionEvent: The current motion event. This value cannot be null.

Returns
boolean	true if the OnGestureListener consumed the event, else false.

onTouchEvent

Added in API level 1

public boolean onTouchEvent (MotionEvent ev)

Analyzes the given motion event and if applicable triggers the appropriate callbacks on the OnGestureListener supplied.

Parameters
ev	MotionEvent: The current motion event. This value cannot be null.

Returns
boolean	true if the OnGestureListener consumed the event, else false.

setContextClickListener

Added in API level 23

public void setContextClickListener (GestureDetector.OnContextClickListener onContextClickListener)

Sets the listener which will be called for context clicks.

Parameters
onContextClickListener	GestureDetector.OnContextClickListener: the listener invoked for all the callbacks, or null to stop listening for context clicks.

setIsLongpressEnabled

Added in API level 1

public void setIsLongpressEnabled (boolean isLongpressEnabled)

Set whether longpress is enabled, if this is enabled when a user presses and holds down you get a longpress event and nothing further. If it's disabled the user can press and hold down and then later moved their finger and you will get scroll events. By default longpress is enabled.

Parameters
isLongpressEnabled	boolean: whether longpress should be enabled.

setOnDoubleTapListener

Added in API level 3

public void setOnDoubleTapListener (GestureDetector.OnDoubleTapListener onDoubleTapListener)

Sets the listener which will be called for double-tap and related gestures.

Parameters
onDoubleTapListener	GestureDetector.OnDoubleTapListener: the listener invoked for all the callbacks, or null to stop listening for double-tap gestures.