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Django: multiple models in one template using forms [closed]
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This really isn't too hard to implement with ModelForms. So lets say you have Forms A, B, and C. You print out each of the forms and the page and now you need to handle the POST.
if request.POST():
a_valid = formA.is_valid()
b_valid = formB.is_valid()
c...
Why does UITableViewCell remain highlighted?
...l to remain highlighted after being touched? I click the cell and can see it stays highlighted as a detail view is pushed. Once the detail view is popped, the cell is still highlighted.
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Why shouldn't Java enum literals be able to have generic type parameters?
Java enums are great. So are generics. Of course we all know the limitations of the latter because of type erasure. But there is one thing I don't understand, Why can't I create an enum like this:
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Defining a variable with or without export
...ss. You would use this for (say) loop variables, temporary variables etc.
It's important to note that exporting a variable doesn't make it available to parent processes. That is, specifying and exporting a variable in a spawned process doesn't make it available in the process that launched it.
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Getting the last element of a list
...ist[-1] is the shortest and most Pythonic.
In fact, you can do much more with this syntax. The some_list[-n] syntax gets the nth-to-last element. So some_list[-1] gets the last element, some_list[-2] gets the second to last, etc, all the way down to some_list[-len(some_list)], which gives you the f...
Why is it faster to check if dictionary contains the key, rather than catch the exception in case it
...to be unwound etc.
On the other hand, accessing a value in a dictionary by its key is cheap, because it's a fast, O(1) operation.
BTW: The correct way to do this is to use TryGetValue
obj item;
if(!dict.TryGetValue(name, out item))
return null;
return item;
This accesses the dictionary only ...
How to check that a string is an int, but not a double, etc.?
...eger beforehand, so that I can give a helpful error message to the user if it's wrong. PHP has is_int() , but that returns false for string like "2" .
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Git alias with positional parameters
...most obvious way is to use a shell function:
[alias]
files = "!f() { git diff --name-status \"$1^\" \"$1\"; }; f"
An alias without ! is treated as a Git command; e.g. commit-all = commit -a.
With the !, it's run as its own command in the shell, letting you use stronger magic like this.
UPD...
How to get the return value from a thread in python?
...utures
def foo(bar):
print('hello {}'.format(bar))
return 'foo'
with concurrent.futures.ThreadPoolExecutor() as executor:
future = executor.submit(foo, 'world!')
return_value = future.result()
print(return_value)
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Are there conventions on how to name resources?
...ow whether there are any official recommendations.
For ids in my layouts with widgets and containers, I use the convention:
<layout>_<widget/container>_<name>
I do the same strategy for any dimens, strings, numbers, and colors I use in those layouts. However, I do try generaliz...