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Change the name of a key in dictionary
...>>> dictionary['ONE'] = dictionary.pop(1)
Traceback (most recent call last):
File "<input>", line 1, in <module>
KeyError: 1
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Android add placeholder text to EditText
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Thanks! I didn't know what they call it in android, I just know that on iOS it's called placeholder.
– Mona
Nov 22 '11 at 4:24
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What is meaning of boolean value returned from an event-handling method in Android
... in the rest of the events in that gesture. A "gesture" in this case means all events until the final ACTION_UP or ACTION_CANCEL. Returning false from an ACTION_DOWN means you do not want the event and other views will have the opportunity to handle it. If you have overlapping views this can be a si...
Java Enum definition
...? By making the type argument the new type itself. So if I've got an enum called StatusCode, it would be equivalent to:
public class StatusCode extends Enum<StatusCode>
Now if you check the constraints, we've got Enum<StatusCode> - so E=StatusCode. Let's check: does E extend Enum<S...
Difference between decimal, float and double in .NET?
...n a decimal form, and expect exact results in decimal representations; not all decimal numbers are exactly representable in binary floating point – 0.1, for example – so if you use a binary floating point value you'll actually get an approximation to 0.1. You'll still get approximations when usi...
Remove the last three characters from a string
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read last 3 characters from string [Initially asked question]
You can use string.Substring and give it the starting index and it will get the substring starting from given index till end.
myString.Substring(myString.Length-3)
Retrieves a substring from this...
How do I query between two dates using MySQL?
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Personally, I find the term 'from' and 'to' a sneaky way to remember the order in which the query should be written.
– KeaganFouche
Jan 21 '19 at 22:04
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Django using get_user_model vs settings.AUTH_USER_MODEL
...s.AUTH_USER_MODEL will delay the retrieval of the actual model class until all apps are loaded. get_user_model will attempt to retrieve the model class at the moment your app is imported the first time.
get_user_model cannot guarantee that the User model is already loaded into the app cache. It mi...
How to set delay in android?
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This solution explained all the questions that I had with handlers at some lines of code.
– Sierisimo
May 19 '15 at 17:55
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Why does scanf() need “%lf” for doubles, when printf() is okay with just “%f”?
...cross-use" %lf with float or %f with double.
But there's no reason to actually do it in practice. Don't use %f to printf arguments of type double. It is a widespread habit born back in C89/90 times, but it is a bad habit. Use %lf in printf for double and keep %f reserved for float arguments.
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