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How do negative margins in CSS work and why is (margin-top:-5 != margin-bottom:5)?
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Negative margins are valid in css and understanding their (compliant) behaviour is mainly based on the box model and margin collapsing. While certain scenarios are more complex, a lot of common mistakes can be avoided after studying the spec.
For instance, r...
How to measure time in milliseconds using ANSI C?
...nction only measures the amount of time that a process has spent executing and is not accurate on many systems.
You can use this function like this:
struct timeval tval_before, tval_after, tval_result;
gettimeofday(&tval_before, NULL);
// Some code you want to time, for example:
sleep(1);
g...
Best practice to mark deprecated code in Ruby?
...a method as deprecated, so the people using it can easily check their code and catch up. In Java you set @Deprecated and everybody knows what this means.
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SQLiteDatabase.query method
...By using the Where/Bind -Args version you get automatically escaped values and you don't have to worry if input-data contains '.
Unsafe: String whereClause = "column1='" + value + "'";
Safe: String whereClause = "column1=?";
because if value contains a ' your statement either breaks and you get ex...
How does push notification technology work on Android?
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From what I've heard during an Android developers conference in Israel:
There is simply a TCP socket waiting in accept mode on a cloud Google server. The TCP connection had been initiated by the Google Play application. That's why Google Play must be inst...
Most simple but complete CMake example
... by how CMake works. Every time I think that I am getting closer to understand how CMake is meant to be written, it vanishes in the next example I read. All I want to know is, how should I structure my project, so that my CMake requires the least amount of maintainance in the future. For example, I ...
Can I start the iPhone simulator without “Build and Run”?
I want to delete an app in the simulator before I "build and run". How can I start the simulator so I can do the deletion? If I start it by "build and run" I get a long log output that takes a while because of a bug I'm trying to fix. I'd like to avoid that.
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How can I measure the speed of code written in PHP? [closed]
... two solutions :
The quite "naïve" one is using microtime(true) tobefore and after a portion of code, to get how much time has passed during its execution ; other answers said that and gave examples already, so I won"t say much more.
This is a nice solution if you want to benchmark a couple of in...
Stretch and scale a CSS image in the background - with CSS only
I want that my background image stretch and scale depending on the browser viewport size.
22 Answers
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How do I include a file over 2 directories back?
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@Brian Well, that’s nonsense, you’re comparing apples and oranges. You’re right that a define would be used here but (1) that wasn’t even remotely the question here. And (2) you’d still use a relative path in your define, Unless you actually hard-code the whole absolute se...