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Method call if not null in C#
...nvoke" problem.
===
Prior to C# 6, no: there is no null-safe magic, with one exception; extension methods - for example:
public static void SafeInvoke(this Action action) {
if(action != null) action();
}
now this is valid:
Action act = null;
act.SafeInvoke(); // does nothing
act = delegate...
Android Spinner: Get the selected item change event
...
But what if the user selects the "default" item, the one up the top? Then onItemSelected(...) is not hit. (I know because I just found this out the hard way.)
– Andrew Wyld
Mar 23 '12 at 16:40
...
NuGet Package Restore Not Working
I checked in a project on one computer, checked out on another, and find that the binaries installed by NuGet are missing. I could check them in to source control as well, but it looks like there's a better solution:
...
Inherit from a generic base class, apply a constraint, and implement an interface in C#
...ch is inheriting from a generic base class and is applying a constraint to one of the type parameters. I also want the derived class to implement an interface. For the life of me, I cannot seem to figure out the correct syntax.
...
Is there a way to run Bash scripts on Windows? [closed]
...nd I use Windows 7 Ultimate, and I like to use it to develop applications. One of the down sides (as with every OS) is that I can not run Bash scripts. Is there a way to run Bash scripts on Windows by installing some software? It is ok if it does not work 100%, but as long as the most common functio...
Postgresql: password authentication failed for user “postgres”
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Very nice one. To other new users, DON'T FORGET THE SEMICOLON at the end of the ALTER USER line.
– itsols
Nov 1 '13 at 16:18
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How to Create a circular progressbar in Android which rotates on it?
... answer:
Instead of creating a layer-list, I separated it into two files. One for ProgressBar and one for its background.
This is the ProgressDrawable file (@drawable folder): circular_progress_bar.xml
<?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.c...
java.lang.UnsupportedClassVersionError: Bad version number in .class file?
...Now, all the suggestions on the web indicate that the code was compiled in one version and executed in another version (new on old). However, I only have one version of JRE on my system. If I run the commands:
...
Pro JavaScript programmer interview questions (with answers) [closed]
...ly have that answer, and should probably mention function-level scope. Anyone calling themselves an "advanced" JS programmer should be prepared to talk about locals, implied globals, the window object, function-scope, declaration hoisting, and scope chains. Furthermore, I'd love to hear about [[Do...
Android YouTube app Play Video Intent
...rse("vnd.youtube://" + video_id));
startActivity(intent);
Now that I've done some more research, it looks like I only needed 'vnd.youtube:VIDEO_ID' instead of two slashes after the colon (':' vs. '://'):
http://it-ride.blogspot.com/2010/04/android-youtube-intent.html
I tried most of the suggesti...