Скачать или смотреть Use the android proximity sensor

The proximity sensor lets you determine how far away an object is from a device. The proximity sensor is usually used to determine how far away a person's head is from the face of a handset device (for example, when a user is making or receiving a phone call). Most proximity sensors return the absolute distance, in cm, but some return only near and far values. On some device models, the proximity sensor is located underneath the screen, which can cause a blinking dot to appear on the screen if enabled while the screen is on. Some proximity sensors return binary values that represent "near" or "far." In this case, the sensor usually reports its maximum range value in the far state and a lesser value in the near state. Typically, the far value is a value greater than 5 cm, but this can vary from sensor to sensor.
Watch more Android-powered devices with built-in sensors that measure motion, orientation, and various environmental conditions in the playlist :
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