[Guide] How to use the CLOCK


J'utilise MIT APP inventor depuis peu.
J'ai lu le tutoriel très intéressant.

Par contre, je dois être niais, mais je n'arrive pas à faire afficher une image pendant une durée défini (Exemple : afficher une image pendant 2 secondes puis elle disparaît).

Merci pour votre aide.

You can for examlple When Screen initialize set image visible to true, Set Clock.Timer Interval to 2000 , set Clock.Timer Enabled to true and then use block when Clock.Timer set image.visible to false and Clock.Timer Enabled to false

Oui c'est logique et si simple. :sweat_smile:


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I've been working on a way to set the time on an ESP32 over BLE, eventually I found a way. I used the included Arduino code on the ESP32, adapted with the use of the ESP32Time library, as this allows you to set the RTC directly, most solutions involve connecting to the internet to get the time from an NTP server, my product will be carried around across the world to getting the time from a phone makes much more sense.


  • BLE works with short strings, this meant converting the millis clock to a string, I added "" to it to get that to happen. Other ways are suggested but they didn't work for me.
  • Although the system time took into account the UTC offset, the millis time didn't, adding the result of the 'Z' format didn't work either, the less well-known 'X' format for time zone offset did.

Perhaps it's easier to see by looking at my blocks, there's a bit added for debugging. I'm using a variable tzone1 to pass the UTC offset around.

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Hey everyone.. i read this article a bunch of times, but i still have no clue on how to make a simple delay.. can anyone help?


Thanx. a wonderfull blog page

Hi, Hope help U
Pause.aia (2,1 KB)

Thanks a bunch! it helped :grin:

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It will end in tears if you take that approach!! :rage:

Like this:



hi same here i have also not understand. But, follow these step which is above 'how to make a clock' :slight_smile:

Why is a wait procedure generally a bad idea?
The model of event processing in App Inventor by Lyn

Please Wait method by Scott



I wonder if writing these pause procedures correlates with having a sleep disorder, where the coder retires to their bed at night but just lies there all night staring at their clock?

I knew some one with an autistic child. The child never slept at night. It wrecked the parent's health.

The Clock Timer requires a leap of faith.

It requires you to fall off the end of your current Event block, and accept that control will resume in a Clock Timer or another Event block.

This may come as a surprise to people who started out coding in non-event oriented environments.


Is true, I change my program, with enable a clock, and change the action with a variable, then disable the cloc. Is easier. Thanks TIMAI2

Did you mention which builder are you using, I don't think this is MIT App Inventor, at all :thinking:

Hi I am very new to this site so I don't know anything, this will probably will be of use to me!

Actually looks like it is App Inventor - it's just the colour resolution of the screen the images were captured from?


actually, it looks like kodular, which is not app inventor

and the checkboxes of the properties look so purple but in app inventor it's blue

Actually, it really doesn't matter....


But if the things are different on another builder, I am only concerned abut that...