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Android: How can I get the current foreground activity (from a service)?
Is there a native android way to get a reference to the currently running Activity from a service?
12 Answers
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What is the difference between join and merge in Pandas?
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I always use join on indices:
import pandas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l ...
Getting raw SQL query string from PDO prepared statements
...the final SQL query, with parameter values interpolated into it. I understand that this would be useful for debugging, but it is not the way prepared statements work. Parameters are not combined with a prepared statement on the client-side, so PDO should never have access to the query string combi...
Can I exclude some concrete urls from inside ?
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The standard Servlet API doesn't support this facility. You may want either to use a rewrite-URL filter for this like Tuckey's one (which is much similar Apache HTTPD's mod_rewrite), or to add a check in the doFilter() method of th...
How can I configure NetBeans to insert tabs instead of a bunch of spaces?
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Go to Tools-> Options-> Editor-> Formatting and uncheck Expand tabs to spaces:
Ensure you also pick coherent values for "Number of Spaces per indent" and "Tab Size".
Additionally, you can check all the items in the Language combo and make sure they all use the ge...
MySQL > Table doesn't exist. But it does (or it should)
I changed the datadir of a MySQL installation and all the bases moved correctly except for one.
I can connect and USE the database. SHOW TABLES also returns me all the tables correctly, and the files of each table exists on the MySQL data directory.
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Why do we have to specify FromBody and FromUri?
Why are the FromBody and FromUri attributes needed in ASP.NET Web API`?
4 Answers
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PostgreSQL function for last inserted ID
...an id column created with the SERIAL pseudo-type. To avoid relying on this and to feel more clean, you can use instead pg_get_serial_sequence:
INSERT INTO persons (lastname,firstname) VALUES ('Smith', 'John');
SELECT currval(pg_get_serial_sequence('persons','id'));
Caveat: currval() only work...
How to create a unique index on a NULL column?
...f uniques" -- NULL is a special value in SQL (similar in many ways to NaN) and needs to be treated accordingly. It's actually a failure in in SQL Server to honor various SQL specifications: here is a link for a request for the "correct implementation" for what it is worth: connect.microsoft.com/SQLS...
What is the best way to filter a Java Collection?
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Java 8 (2014) solves this problem using streams and lambdas in one line of code:
List<Person> beerDrinkers = persons.stream()
.filter(p -> p.getAge() > 16).collect(Collectors.toList());
Here's a tutorial.
Use Collection#removeIf to modify the collection...