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Placeholder in UITextView

My application uses an UITextView . Now I want the UITextView to have a placeholder similar to the one you can set for an UITextField . ...
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How to install packages offline?

...env2. python -m virtualenv myenv2 cd myenv2 source bin/activate cd - ls now you can go to your offline folder where your requirements.txt and tranferred_packages folder are in there. download the packages with following code and put all of them to tranferred_packages folder. pip download -r requ...
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What is Type-safe?

... Personally, I prefer to have my compiler tell me if I made that mistake. Now, back to C#... C# supports a language feature called covariance, this basically means that you can substitute a base type for a child type and not cause an error, for example: public class Foo : Bar { } Here, I cre...
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SQLAlchemy default DateTime

...key=True) created_date = Column(DateTime, default=datetime.datetime.utcnow) share | improve this answer | follow | ...
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How to get object size in memory? [duplicate]

I need to know how much bytes my object consumes in memory (in C#). for example how much my Hashtable , or SortedList , or List<String> . ...
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How to add property to a class dynamically?

... I suppose I should expand this answer, now that I'm older and wiser and know what's going on. Better late than never. You can add a property to a class dynamically. But that's the catch: you have to add it to the class. >>> class Foo(object): ... ...
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How to enable C++11 in Qt Creator?

...elete your duplicate/incomplete answer, all I could do was to downvote it. Now that you have edited it to make it more presentable, I am happy with just the downvote. – nurettin Aug 21 '14 at 12:55 ...
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What are the main performance differences between varchar and nvarchar SQL Server data types?

... @cbmeeks: I don't code for what I don't know. But if you can use it with no noticeable performance hit, then your databases aren't big enough for it to matter... – gbn Mar 7 '12 at 15:48 ...
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All Ruby tests raising: undefined method `authenticate' for nil:NilClass

...er! function is part of Rails 3 (using the new devise feature, of which I know little about). If the app can't find the User model (either because of namespace issues or whatever reason) then the method will fail. The "enki" application you linked to is now a Rails 3 application. It could be expe...
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Use cases for the 'setdefault' dict method

...or them: headers = parse_headers( msg ) # parse the message, get a dict # now add all the optional headers for headername, defaultvalue in optional_headers: headers.setdefault( headername, defaultvalue ) share ...