Closing a compiled App leaves a black empty screen.

ndrorian

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Apr 7, 2019, 12:49:27 PM4/7/19

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I am testing my compiled App on a mobile phone, Moto E4+ with Android 7.1.1. After closing the App the main app screen will go away but a black screen with the App logo will remain on my screen and needs to be closed again. This is not an expected behavior right? and will this be fixed?

SteveJG

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Apr 7, 2019, 12:57:30 PM4/7/19

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This might be a bug or it just might be how you code screen changes. You might make a small example that exhibits this behavior Noel and post it here in the forum (an aia is fine) so someone can see what is happening.

When will it be fixed? Probably sometime after someone can recreate your situation and determine if it is a bug.

Regards,

Steve

ndrorian

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Apr 8, 2019, 1:15:35 PM4/8/19

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Hi Steve,

I have attached the .aia of a mini app that behaves the same way.

Thanks

Noel

TODTest.aia

TimAI2

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Apr 8, 2019, 2:49:42 PM4/8/19

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No issues here with that TODTest app on Samsung A3 Android 6.01

ndrorian

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Apr 9, 2019, 12:38:23 PM4/9/19

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So, what's next?

Does MIT have a lab that can test this with different phones and current Android version?

BodyMindPower

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Apr 9, 2019, 2:14:41 PM4/9/19

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"...a black screen with the App logo will remain on my screen..."

what App logo, where it come from?

make a screenshot of that and post it

Anke

Chris Ward

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Apr 9, 2019, 2:16:29 PM4/9/19

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Tested APK on:

Lenovo A816 OS 4.4.4

Samsung S8 OS 9.0

No issue, so I suspect it might be a Motorola thing?

However, your App Exit is not "clean" - the Clock timer is not switched off. Try this:

ndrorian

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Apr 10, 2019, 2:17:41 PM4/10/19

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I have the same issue after adding "set Clock1.TimerEnabled to False".

Screen shot:

Screen Shot 2019-04-10 at 11.16.39 AM.png

Chris Ward

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Apr 10, 2019, 4:59:15 PM4/10/19

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Hi ndorian

Do you have a non-motorola device to perform the same test on?

BodyMindPower

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Apr 10, 2019, 5:09:12 PM4/10/19

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Try if the problem arises even without a clock component. So just use a button to close the app. If the problem persists then it will certainly depend on the device.

Anke

BodyMindPower

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Apr 11, 2019, 5:09:03 AM4/11/19

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... and try also this:

at least one of them should work ...

(but I think there is no need to close app from the app itself)

ndrorian

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Apr 11, 2019, 12:40:40 PM4/11/19

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1- I tested BodyMindPower suggestion by creating a CLOSETest.apk with only the two buttons. Close screen and close application work the same way by just hiding the application. Same issue.

2- I tested the CLOSETest and my main app on a Samsung Galaxy Tab A, Model SM-T280 with Android 5.1.1. I have the same behavior as on Motorolla. The black App screen remains.

Thanks,

Noel

BodyMindPower

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Apr 11, 2019, 1:51:49 PM4/11/19

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Close screen and close application work the same way by just hiding the application. Same issue.

Does this mean that if you press the button close screen, has the same result as if you simply press the "back" button of the device? The black window with the app icon remains? That would be really a strange issue.

Anke

ndrorian

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Apr 12, 2019, 12:07:19 PM4/12/19

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Yes, Close screen has the same result as if you press the back button.

Chris Ward

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Apr 12, 2019, 12:20:18 PM4/12/19

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Hi ndrorian

Your post is assigned to MIT, who may contact you directly. Please be patient, they are very busy.

Evan Patton

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Apr 12, 2019, 2:35:44 PM4/12/19

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The screenshot you show indicates to me that whatever customizations Motorola made to the version of Android running on your device, it seems to be interpreting the app as wanting to go into a split-screen mode. I'm not sure why that is, and I'm not sure that it's something we can fix since all we are doing is calling Android's finishActivity method to close the activity (recursively doing so in the case of close application). Is it possible this is something controlled by the Android Settings?

Regards,

Evan

ndrorian

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Apr 13, 2019, 12:32:16 PM4/13/19

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The same behavior happens on 3 devices. A Samsung J3 with Android 7.1.1, Samsung Galaxy Tab A, Model SM-T280 with Android 5.1.1 and my Moto E4+ with Android 7.1.1.

Regards,

Noel

BodyMindPower

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Apr 13, 2019, 3:41:30 PM4/13/19

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Is this behavior only with AI2 apps (APKs)? Maybe a compiling issue. If yes, upload your APK to Google Drive oder anywhere and send me the link by Mail. I can check ...

Anke

Chris Ward

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Apr 14, 2019, 6:15:23 AM4/14/19

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Hello Noel

That knocks the Motorola theory on it's head then :)

What Browser (Name/Version) are you using to run App Inventor?

BodyMindPower

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Apr 14, 2019, 7:08:09 AM4/14/19

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no issues with APK on several devices (also Motorola) at all ...

Chris Ward

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Apr 14, 2019, 7:53:48 AM4/14/19

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Another thought Noel

Looking for a common denominator across your range of devices. Something they all have installed that results in this issue. Of most interest, something that runs when the device is switched on - an anti-virus app for example.

ndrorian

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Apr 14, 2019, 11:48:29 AM4/14/19

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All my devices are vanilla.

Currently I use Chrome Version 73.0.3683.86 (Official Build) (64-bit)

Previously I used Safari Version 12.0.3 (14606.4.5)

Builds with both browsers have the same issue.

On MacBook Pro (13-inch, 2017, Two Thunderbolt 3 ports) with Mac Os Mojave version 10.14.3.

Thanks

Noel

Chris Ward

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Apr 14, 2019, 6:32:06 PM4/14/19

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Right - so the devices should be good to go, but what about the Mac? Does it have an anti-virus application? I'm wondering if App Inventor's compiling is regarded as suspicious. Certainly on Windows OS there have been cases where the AV, in checking files, introduced corruption (not seen it happen to App Inventor).

Do you have access to another PC to try?

Chris Ward

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Apr 25, 2019, 6:21:32 PM4/25/19

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Hi Noel

Any luck?

ndrorian

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Apr 25, 2019, 9:09:27 PM4/25/19

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I don't have access to another PC but I tested the issue by building the CLOSETest.apk on a MACBOOK Air and the build has the same issue as my builds.

This seems to be an issue with AI2 on MAC.

Chris Ward

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Apr 26, 2019, 8:57:07 AM4/26/19

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I think you are right. Do not have a clue as to how or why though. When App Inventor is ready to produce iOS Apps on the Mac, we might learn more.

ndrorian

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Apr 26, 2019, 11:17:00 AM4/26/19

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Will this issue be added to the list of things to be fixed in the future?

Chris Ward

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Apr 26, 2019, 11:45:27 AM4/26/19

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Hi Noel

If MIT can reproduce it, then yes.

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