Stopwatch Timer Accurate to milliseconds

[Quentin Sanders]

Hello I am currently trying to make a stopwatch using app inventor 2.  I need the stopwatch to be accurate to 1/1000th of a second.  I have been able to get it to be accurate to a 1/100th of a second, but anytime I try to make the stopwatch more accurate it runs far to slow.  Does anyone know anyways to solve this problem?  Thanks. 

[SteveJG]

Probably not possible Quentin  ... see  http://gamasutra.com/view/feature/171774/getting_high_precision_timing_on_.php?print=1  there might be something there you can use.

An additional problem is that that the AI2 graphics are notoriously slow when compared with apps built with Java based compilers.  If you post the timing data to the screen in real time, there will be a lag.  This might be mitigated by posting only the beginning and ending time, without the intervening  1/1000th seconds.  Realize 1/1000 is —300x faster than a human blink

[Taifun]

you will get the best result, if after starting you store the start time and in the end calculate end time - start time

Taifun

[Quentin Sanders]

Would you happen to have an example of what that would look like? 

[Quentin Sanders]

@Taifun

[Taifun]

what have you tried?

see also Scott's example here https://groups.google.com/d/msg/app-inventor-developers-library/6eknWf2cJN0/nuZ_6NmjHnMJ

Taifun

[Quentin Sanders]

Scott's method is the method that I tried initially, and how my code currently looks now more or less. I had tried modifying that code so that it only showed seconds and milliseconds.  But it always seemed to run to slow or would never match up correctly with the clock on my computer. 

[Scott Ferguson]

This example shows how I would attempt to set a counter for 100ths of a second.

The Clock component is set to an interval of 0.

Set Label3.Text to 0 initially.

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sf