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How to make an app's background image repeat
I have set a background image in my app, but the background image is small and I want it to be repeated and fill in the whole screen. What should I do?
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JPA: unidirectional many-to-one and cascading delete
...cade REMOVE operations so that EntityManager.remove will remove the parent and the children. You can also specify orphanRemoval as true, to delete any orphaned children when the child entity in the parent collection is set to null, i.e. remove the child when it is not present in any parent's collect...
Hash Map in Python
... The second example just builds a dict in the same ways as before and then copies it. The other use dict, which would be more appopriate in this context, is dict(key1=value1, key2=value2, ...) but that requires the keys to strings which are also valid Python identifiers (and internally, thi...
Select rows which are not present in other table
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There are basically 4 techniques for this task, all of them standard SQL.
NOT EXISTS
Often fastest in Postgres.
SELECT ip
FROM login_log l
WHERE NOT EXISTS (
SELECT -- SELECT list mostly irrelevant; can just be empty in Postgres
FROM ip_location
WHERE ip = l.ip
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IE10 renders in IE7 mode. How to force Standards mode?
...ssumption that most webpages were written to target earlier versions of IE and looks at the doctype, meta tags and HTML to determine the best compatibility mode (sometimes incorrectly). Even with a HTML5 doctype IE will still place your website in compatibility mode if it's an intranet site.
To ens...
RESTful API methods; HEAD & OPTIONS
I'm writing a RESTful API module for an application in PHP, and I'm a bit mixed on the verbs HEAD and OPTIONS .
3 Answer...
Python Pandas merge only certain columns
...e to only merge some columns? I have a DataFrame df1 with columns x, y, z, and df2 with columns x, a ,b, c, d, e, f, etc.
5...
How can I make a div not larger than its contents?
...nter the parent of the table by setting "text-align:center" on it's parent and "text-align:left" on it (e.g. <body style="text-align:center"><span style="text-align:left; display:inline-block;"><table>...</table></span></body>)
– bernstein
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How to log a method's execution time exactly in milliseconds?
...Since(methodStart)
print("Execution time: \(executionTime)")
Easy to use and has sub-millisecond precision.
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Authorative way to override onMeasure()?
...ding onMeasure()? I've seen various approaches. For example, Professional Android Development uses MeasureSpec to calculate the dimensions, then ends with a call to setMeasuredDimension(). For example:
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