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Which is best way to define constants in android, either static class, interface or xml resource?
... advantages of using project resources is the ease of access and that they allow you to organize your project significantly.
static final constants are compiled into the java bytecode; project resources are compiled into a binary format within the apk. Accessing either is extremely efficient... if ...
Entity Framework: There is already an open DataReader associated with this Command
I am using Entity Framework and occasionally i will get this error.
17 Answers
17
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How to add items to a spinner in Android?
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While this may theoretically answer the question, it would be preferable to include the essential parts of the answer here, and provide the link for reference.
– Bill the Lizard
Jan 26 '12 at 21:00
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Disable a Button
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I also get an error if I change (_ sender: ) to UIButton . The error reads: Value of type '(UIButton) -> ()' has no member 'isEnabled'
– user9470831
Feb 5 '19 at 4:25
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E11000 duplicate key error index in mongodb mongoose
... null value.
In other words, a sparse index is ok with multiple documents all having null values.
sparse indexes
From comments:
Your error says that the key is named mydb.users.$email_1 which makes me suspect that you have an index on both users.email and users.local.email (The former being old an...
Remove Object from Array using JavaScript
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This however will remove all the occurrences found, not only the first one
– Flavien Volken
Jul 12 '16 at 6:49
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dplyr: “Error in n(): function should not be called directly”
...ction" specification, like example below:
delay <- dplyr::summarise(by_tailnum,
count = n(),
dist = mean(distance, na.rm = TRUE),
delay = mean(arr_delay, na.rm = TRUE))
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How do you create a Swift Date object?
... dateFromString. If you wanted to return a nil on bad parses, you would ideally use a failible initializer; but you cannot do that now (June 2015), because of a limitation in Swift 1.2, so then you're next best choice is to use a class factory method.
A more elaborate example, which addresses both ...
How to check if std::map contains a key without doing insert?
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Use my_map.count( key ); it can only return 0 or 1, which is essentially the Boolean result you want.
Alternately my_map.find( key ) != my_map.end() works too.
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How can I change my Cygwin home folder after installation?
I just installed Cygwin, and it looks like the home directory in the bash prompt is on my Z: drive. That's not where I want it.
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