Android: NullPointerException when trying to load videoview through AsyncTask
What is a NullPointerException, and how do I fix it?
How to output multiple image sizes from one design? I am designing an app for Android and as you may know that Android uses 6 different density buckets from LDPI to XXXHDPI.   Is there a way to save multiple outputs of different sizes from one design using either Photoshop, Illustrator, or another software?  If not will I have to resize it 6 times or is there an easy way? Why aliases in a non-interactive Bash shell do not work Is installing wine in Ubuntu safe? $\frac{1}{99989999} = 1.00010002000300050008001300210034005500890144... \times 10^{-8}$    (), which includes the Fibonacci sequence $(1\ 1\ 2\ 3\ 5\ 8\ 13\ 21\ 55\ 89\ 144\ldots )$.  This is fascinating to me but I can't figure out how this works, and a Google search doesn't seem to reveal anything. "invalid use of incomplete type" error with partial template specialization When updating, I get the following error message:   W: The repository 'http://ppa.launchpad.net/mc3man/trusty-media/ubuntu xenial Release' does not have a Release file.   Here, I find another statement on this error:   This recommends removing certain PPAs; and, I'm not sure if I should do that since it might mean not getting the updates that I need.    Is this what I should do? How does Azkaban's management work? I was under the impression that only Dementors are guarding the prison of Azkaban and are only there to keep the inmates on their cells, though after reading again the following passage it put me into thoughts:     'One night, when (the Dementors) opened my door to bring food, I   slipped past them as a dog. It's so much harder for them to sense   animal emotions that they were confused ... I was thin enough to slip   through the bars. I swam as a dog back to the mainland. I journeyed   north and slipped into the Hogwarts grounds as a dog. I've been living   in the Forest ever since.'       Prisoner of Azkaban; chapter 'The Servant of Lord Voldemort'   So Sirius says that he escaped from his cell when the Dementors brought him food.... I say what??? Dementors dont obey anyone, not even the commands of the Ministry of Magic.  So the actual question is, How is the Azkaban prison managed? e.g. who cooks the food? the inmates have blankets, who is washing these blankets etc etc I know there is something wrong with this but I don't know where. It's some kind of a math fallacy and it is driving me crazy. Here it is: $$-1= (-1)^3 = (-1)^{6/2} = \sqrt{(-1)^6}= 1?$$ Can a wizard using an arcane focus quarterstaff and a shield still cast somatic component spells? If there is a wizard that, by some means, has acquired proficiency in the use of shields, can said wizard use his shield in one hand and his arcane focus quarterstaff in the other and still cast somatic component spells?  Since the quarterstaff has been crafted to also be an arcane focus, and the Sage Advice Compendium states that you can provide the somatic components of spells with the same hand wielding the arcane focus, in this case an arcane focus quarterstaff, could that wizard still be able to perform somatic component spells while using a shield in the other?  I understand War Caster is the feat that allows you to cast somatic component spells even while using a shield and weapon or two weapons in each hand, but is this a simple way around those rules seeing as this "weapon" is your arcane focus? I would like to believe it is not, but I'm not fully fluent in the ways of spellcasting. Site.createPortalUser() returning null in test context My friend and I are planning a vacation to Ireland later this year. We'll be there for a week, flying into Dublin and then renting a car and driving around the country.  Both of us are 23. Are there any age restrictions on renting cars in Ireland? What would be the cheapest/best option for us? What was Tauriel doing during the events of The Lord of the Rings movies? [Yes, The Hobbit movies are nonsense. But how could I call myself a fantasy fan if I didn't demand my nonsense be as logical as possible?]  Tauriel is presented as a highly-skilled fighter and a combatant for the side of good. Despite this, she apparently did nothing during Sauron's war on the free peoples.  Was she somehow     still mourning Killi, after all these decades?   Was she dead? Or is there another reason she didn't participate? In logic, a semantics is said to be compact iff if every finite subset of a set of sentences has a model, then so to does the entire set.   Most logic texts either don't explain the terminology, or allude to the topological property of compactness. I see an analogy as, given a topological space X and a subset of it S, S is compact iff for every open cover of S, there is a finite subcover of S. But, it doesn't seem strong enough to justify the terminology.   Is there more to the choice of the terminology in logic than this analogy? Since , how do I uninstall it from my desktop system?  (Please note: This question is not about Unity 7, which is still supported at the time of this writing and should remain installed if present.) Determine the Galois group of the polynomial $(x^3-2)(x^3-3)(x^2-2)$ over $\mathbb{Q}(\sqrt {-3})$ Determine the Galois group of the polynomial $(x^3-2)(x^3-3)(x^2-2)$ over $\mathbb{Q}(\sqrt {-3})$.   I tried to decompose the splitting field into a tower, but then it is very complicated in each step and since the degree is large, I cannot determine the group by guessing. It seems to me that Kummer theory might work, but there are $2$-degree and $3$-degree factors. how to disable system apps without root? Is there a rational number between any two irrationals? Suppose $i_1$ and $i_2$ are distinct irrational numbers with $i_1 &lt; i_2$.  Is it necessarily the case that there is a rational number $r$ in the interval $[i_1, i_2]$?  How would you construct such a rational number?  [I posted this only so that the useful answers at  could be merged here before that question was deleted.] What's wrong with this division? I think there's a lot for me to learn about data types. Why this happens  double result = ((3/8)*100).ToString();   it gives zero .. should be 37,5 ... :( Geometric intuition of improper integrals I am aware that the area under the curve of $\frac{1}{x}$ is infinite yet the area under the curve of $\frac{1}{x^2}$ is finite.   Calculus and series wise, I understand what is going on, but I can't seem to get a good geometric intuition of the problem. Both curves can be shown to converge to $0$ (the curves themselves, not the area), and on the interval from $1$ to infinity, the two curves have nothing intrinsically different. Can someone please provide me with an good geometric intuition of what's going on? I can't find anything on the web, people seem to not want to explain it geometrically. How do I monitor the computer's CPU, memory, and disk usage in Java?