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How do I show/hide a UIBarButtonItem?
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Save your button in a strong outlet (let's call it myButton) and do this to add/remove it:
// Get the reference to the current toolbar buttons
NSMutableArray *toolbarButtons = [self.toolbarItems mutableCopy];
// This is how you remove the button from the toolbar and ...
Is a memory leak created if a MemoryStream in .NET is not closed?
...se. A MemoryStream, on the other hand, stores a managed byte array in its _buffer variable, which is not freed at disposal time. In fact, the _buffer is not even nulled in the MemoryStream's Dispose method, which is a SHAMEFUL BUG IMO because nulling the reference could make the memory eligible fo...
How do you change the size of figures drawn with matplotlib?
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figure tells you the call signature:
from matplotlib.pyplot import figure
figure(num=None, figsize=(8, 6), dpi=80, facecolor='w', edgecolor='k')
figure(figsize=(1,1)) would create an inch-by-inch image, which would be 80-by-80 pixels unless you...
Use CSS3 transitions with gradient backgrounds
...und-size: 100% 90px;
background-position: 0 -30px;
-webkit-transition: all 0.2s linear;
-moz-transition: all 0.2s linear;
-o-transition: all 0.2s linear;
transition: all 0.2s linear;
}
Hover state
.btn:hover {
background-position: 0 0;
}
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scheduleAtFixedRate vs scheduleWithFixedDelay
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Try adding a Thread.sleep(1000); call within your run() method... Basically it's the difference between scheduling something based on when the previous execution ends and when it (logically) starts.
For example, suppose I schedule an alarm to go off with a f...
Do HTML WebSockets maintain an open connection for each client? Does this scale?
.../HTML requests. However, that doesn't mean WebSockets is a replacement for all uses of AJAX/HTML.
Each TCP connection in itself consumes very little in terms server resources. Often setting up the connection can be expensive but maintaining an idle connection it is almost free. The first limitation...
Django class-based view: How do I pass additional parameters to the as_view method?
...endation of practices, and in python community it's a rule of thumb to use all of these practices as much as possible to avoid further problems. My linter is always empty when I commit my code :) no matter what.
– holms
Apr 6 '18 at 18:23
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What is the most efficient Java Collections library? [closed]
...ding a lot of functionality over the normal collections in the JDK.
Personally (and I'm biased) I love Guava (including the former Google Java Collections project). It makes various tasks (including collections) a lot easier, in a way which is at least reasonably efficient. Given that collection op...
Should I use an exception specifier in C++?
...y, InterprocessObjectNotImplemented, HardwareUnresponsive );
You could really write that as
throw( ... )
The first is not extensible, the second is overambitious and the third is really what you mean, when you write virtual functions.
Legacy code
When you write code which relies on another lib...
Why is creating a new process more expensive on Windows than Linux?
...eerden: NT has been designed for multi-user from day one, so this is not really a reason. However, you are right about that process creation plays a less important role on NT than on Unix as NT, in contrast to Unix, favors multithreading over multiprocessing.
Rob, it is true that fork is relatively...