tree 253a199287ee65732afeb76a68ae9b981927d103
parent f1034a4131ca824d3d7ca1b9d65473ea90bc3525
author Burcu Dogan <jbd@google.com> 1444415418 -0700
committer Burcu Dogan <jbd@google.com> 1445289710 +0000

exp/sensor: don't enable a sensor on a sender

The underlying implementation was not enabling the sensors on a
particular sender even though the Enable signature accepts different
instances of Sender to enable.

Consider the following program:

  type A struct{}
  func (a A) Send(ev interface{}) {}

  type B struct{}
  func (b B) Send(ev interface{}) {}

  sensor.Enable(A{}, sensor.Gyroscope, time.Millisecond)
  sensor.Enable(B{}, sensor.Accelerometer, time.Millisecond)

is going to compile but only A will be notified when there are new
gyroscope and accelerometer events.

In order to improve the misleading APIs, this CL introduces a
Notify function that users can register a Sender implementation to
listen the changes. If set nil, the sensor package will keep
reading the events but will won't notify.

  sensor.Notify(A{})
  sensor.Enable(sensor.Gyroscope, time.Millisecond)
  sensor.Enable(sensor.Accelerometer, time.Millisecond)

Change-Id: I25e43349e4ae682930baa2d32430f46f24b588b7
Reviewed-on: https://go-review.googlesource.com/15650
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>