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View contents of database file in Android Studio
...t; 3.0:
Open DDMS via Tools > Android > Android Device Monitor
Click on your device on the left.
You should see your application:
Go to File Explorer (one of the tabs on the right), go to /data/data/databases
Select the database by just clicking on it.
Go to the top right corner of the ...
Detect the Internet connection is offline?
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You can determine that the connection is lost by making failed XHR requests.
The standard approach is to retry the request a few times. If it doesn't go through, alert the user to check the connection, and fail gracefully.
Sidenote: To put the entire application in an "off...
Python argparse command line flags without arguments
...nt w is expecting a value after -w on the command line. If you are just looking to flip a switch by setting a variable True or False, have a look at http://docs.python.org/dev/library/argparse.html#action (specifically store_true and store_false)
import argparse
parser = argparse.ArgumentParser()
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Find an element in a list of tuples
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If you just want the first number to match you can do it like this:
[item for item in a if item[0] == 1]
If you are just searching for tuples with 1 in them:
[item for item in a if 1 in item]
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When should you use a class vs a struct in C++?
...d recommend using structs as plain-old-data structures without any class-like features, and using classes as aggregate data structures with private data and member functions.
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When to use thread pool in C#? [closed]
...out when it is best to use a thread pool vs. create my own threads. One book recommends using a thread pool for small tasks only (whatever that means), but I can't seem to find any real guidelines. What are some considerations you use when making this programming decision?
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Should we pass a shared_ptr by reference or by value?
When a function takes a shared_ptr (from boost or C++11 STL), are you passing it:
10 Answers
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How can i get the session object if i have the entity-manager
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JPA 1.0
With JPA 1.0, you'd have to use EntityManager#getDelegate(). But keep in mind that the result of this method is implementation specific i.e. non portable from application server using Hibernate to the other. For example with JBoss you would do:
org.hibernate.Session session = (Session) m...
What is the meaning of prepended double colon “::”?
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@NoniA. are you asking what the second set of double colons does?
– FCo
Jun 2 '17 at 18:48
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Select rows of a matrix that meet a condition
...me(). In that case the previous answers (using subset or m$three) will work, otherwise they will not.
To perform the operation on a matrix, you can define a column by name:
m[m[, "three"] == 11,]
Or by number:
m[m[,3] == 11,]
Note that if only one row matches, the result is an integer vector...