Precise metronome for android

Question

The answer to this question states that we can make a reliable and precise metronome on Android using AudioTrack . We can use MediaPlayer , SoundPool , Thread and Timer as well, but they are always causing a delay. Instead of generating a synthesized sound using AudioTrack , how can we achieve the same effect using custom audio files?

Answer 1

You can try to create your own time counter using System.nanoTime() , when you need precision, you always can use this.

public static long nanoTime()

Returns the current value of the most precise available system timer, in nanoseconds. This method can only be used to measure elapsed time and is not related to any other notion of system or wall-clock time. The value returned represents nanoseconds since some fixed but arbitrary time (perhaps in the future, so values may be negative). This method provides nanosecond precision, but not necessarily nanosecond accuracy. No guarantees are made about how frequently values change. Differences in successive calls that span greater than approximately 292 years (263 nanoseconds) will not accurately compute elapsed time due to numerical overflow.

For example, to measure how long some code takes to execute:

long startTime = System.nanoTime(); // ... the code being measured ... long estimatedTime = System.nanoTime() - startTime;
Returns: The current value of the system timer, in nanoseconds. Since: 1.5

Source:

Oracle Documentation https://docs.oracle.com/javase/1.5.0/docs/api/java/lang/System.html#nanoTime()