I keep running into this, and it's extremely frustrating.
The basic problem is that, in a large number of cases, instead of a screenshot, I get a black screen for some set of devices which reads:
'Could not retrieve the screenshot from this device'.
When I have been able to get the 'Save all screenshots in one .zip file' link to work (it usually doesn't) I have been able to verify that the zipfile is missing the screenshots in question as well.
It appears to be random, in that some screenshots will show up for a device, while others will not be present.
This is not a condition I've experienced when running these automated tests in other environments besides the testdroid cloud.
I have logging before I call solo.takeScreenshot(), which is showing up in the logcat output. However, the corresponding screenshot oftentimes does not show up. While it's possible that this log statement is isused while the screenshot is actually not taken (screenshots are taken on a different thread) this seems unlikely, as many times the missing screenshots will be from the middle of a test where there are screenshots present from later in the test.
I'm running with the 'Automatic screenshots' checkbox disabled, and a 'Screenshot directory' of /sdcard/Robotium-Screenshots.
Any ideas what might be going on? This is severly impacting my ability to diagnose failures.
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