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How to make an Android Spinner with initial text “Select One”?
...our project, e.g. into package com.example.customviews. Now in your layout xml, instead of <Spinner ...> use <com.example.customviews.NoDefaultSpinner ...> The rest of the code can stay the same. Don't forget to add the android:prompt attribute to the <com.example.customviews.NoDefaul...
Passing functions with arguments to another function in Python?
Is it possible to pass functions with arguments to another function in Python?
7 Answers
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Double Iteration in List Comprehension
In Python you can have multiple iterators in a list comprehension, like
10 Answers
10
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How can I add the new “Floating Action Button” between two widgets/layouts
...ttom|right|end
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
...
A python class that acts like dict
... self.__dict__ is not the same as the actual dictionary content. Every python object, regardless of its type, has a _dict__ which contains all the object attributes (methods, fields, etc). You do not want to mess around with this unless you want to write code that is modifying itself...
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How to get the parents of a Python class?
How can I get the parent class(es) of a Python class?
6 Answers
6
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Concurrent.futures vs Multiprocessing in Python 3
Python 3.2 introduced Concurrent Futures , which appear to be some advanced combination of the older threading and multiprocessing modules.
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Define a lambda expression that raises an Exception
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There is more than one way to skin a Python:
y = lambda: (_ for _ in ()).throw(Exception('foobar'))
Lambdas accept statements. Since raise ex is a statement, you could write a general purpose raiser:
def raise_(ex):
raise ex
y = lambda: raise_(Excepti...
u'\ufeff' in Python string
...endian UTF-16 encoding. If you decode the web page using the right codec, Python will remove it for you. Examples:
#!python2
#coding: utf8
u = u'ABC'
e8 = u.encode('utf-8') # encode without BOM
e8s = u.encode('utf-8-sig') # encode with BOM
e16 = u.encode('utf-16') # encode with BOM
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Understanding the map function
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map isn't particularly pythonic. I would recommend using list comprehensions instead:
map(f, iterable)
is basically equivalent to:
[f(x) for x in iterable]
map on its own can't do a Cartesian product, because the length of its output list is ...