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If turning ~3-4 pages forward and back fixes it, then I just implemented an error check that will help. If turning 8-10 pages forward and back fixes it, then there are a few things I can look into. If neither fixes it, then I have some other ideas to try, but I'm not as thrilled about those.
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That does sound promising! I just managed to get another black page, and can confirm that turning 4 pages ahead, and then back, made the page display correctly again.
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(but turning just 3 pages ahead, and then back, the page was still black.)
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That's very interesting. I buffer three pages backward, so that means when you turned four pages, it released the bitmap that was stored for the black page. Hence when you turned back, it was re-rendered properly. What this tells me is that a black image truly was rendered and saved for some reason. Are you currently using the quality render preference setting, or the speed? I just want to double check which PDF render library I should be using.
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I'm using the quality setting (but I've had black pages with both the quality and speed settings)
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I just wrote an automated test that is sitting here randomly loading songs from the library you provided, and turning each page and then analyzing the image to see if it's completely black or transparent. That way the test can run for hours and I'm bound to eventually see the problem (assuming the problem will happen on my tablet). Here's hoping this works!
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Brilliant! I really hope it will work! Thank you!
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Just wondered how this is going... Has the automated test succeeded in producing any black pages yet?
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Not a single one yet. I had run the test for a day straight and never saw a black page. I'm not done trying this out, but I needed to switch gears to work on a few other things. If the automated test does not work, this would indicate that there is something significant about turning the pages with a finger versus programmatically. Perhaps there is more going on when the black page occurs than just page turns (i.e. gestures being fired like a pinch zoom).
Mike
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I just had a sudden thought regarding this - and if this is indeed important, then I'm sorry I didn't think about this earlier.. I just realized that I do keep my tablet in a faux leather Targus case ( http://www.targus.com/uk/foliostand-note...k-thz459eu), and I guess there is a slight possibility that this case is affecting the tablet in some way or another. I haven't seen any weird behavior in any other apps on this tablet, but I have had experiences in my past with (magnetic) phone cases making my phones do strange things. There are no magnets on this Targus case, but as you can see from the pictures, the case attaches to the tablet with straps around the corners. Though the straps don't cover the screen itself in any way, the slight pressure they make on the tablet corners could maybe be enough to produce undesired effects - such as when turning pages. I'll discard the theory as soon as I get a new black page - but until then, I will try playing without the Targus case and see if this solves the problem.
Could I ask you other guys who have had this problem, if you are also keeping your tablet in similar cases, or if you get the black pages even without using a case?
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Is it possible to check for display [register] contents and generate a crash report of some kind when an all black page is detected/created?
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Yes, in theory I could do this (if I'm able to accurately detect this case in code). This is something I would only want to do with a diagnostic build though, so if you are volunteering to be a guinea pig, we certainly can try it out.
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Starting on Monday, I will have a whole month without any performances, so I would very much like to volunteer as a guinea pig then. That being said, I haven't had a single black page after removing the Targus case - but of course, this may be a coincidence.
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06-17-2016, 11:09 PM
(This post was last modified: 06-17-2016, 11:31 PM by Skip.)
I would be willing also even though I don't seem to have any of the problems others have had.
My case is a verizon folding case from ebay. It may have magnets since it starts up when I open the cover.
I was just wondering if there is a good memory checking app just in case there is a memory hardware problem and MSP is trying to store display info in a malfing memory location.
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A while since my last reply here, as things have been running pretty smooth for several weeks now. BUT - I just got a black screen, and this time without using the leather case - so that's yet another theory proven wrong. Any chance that I could try out the diagnostic build you considered making earlier, as suggested by Skip? I have several major recitals coming up quite soon, and would really like to focus on other things than the fear of lurking black pages... Thank you!
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