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Check if a given key already exists in a dictionary and increment it
...on 2.5+). This
from collections import defaultdict
my_dict = defaultdict(int)
my_dict[key] += 1
will do what you want.
For regular Python dicts, if there is no value for a given key, you will not get None when accessing the dict -- a KeyError will be raised. So if you want to use a regular dict...
Dilemma: when to use Fragments vs Activities:
...ould decide by yourself what's best for you. It's usually not that hard to convert an activity to a fragment and vice versa.
I've created a post about this dillema here, if you wish to read some further.
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How to lay out Views in RelativeLayout programmatically?
...d () Added in API level 17. It Generates a value suitable for use in setId(int). This value will not collide with ID values generated at build time by aapt for R.id. Example: tv[l_idx].setId(View.generateViewId());
– AndrewBloom
May 3 '17 at 13:28
...
generating GUID without hyphen
...rcase. A Guid with only uppercase letters can only be achieved by manually converting them all to uppercase, example:
Guid.NewGuid().ToString("N").ToUpper();
A guid with only either letter or digits makes no sense. A guid string representation is hexadecimal, and thus will always (well most likel...
Executing Batch File in C#
...nd out what's happening:
static void ExecuteCommand(string command)
{
int exitCode;
ProcessStartInfo processInfo;
Process process;
processInfo = new ProcessStartInfo("cmd.exe", "/c " + command);
processInfo.CreateNoWindow = true;
processInfo.UseShellExecute = false;
// ...
How to get unique values in an array
...t you have to use Array.from(... new Set(a)) since Set can't be implicitly converted to an array type. Just a heads up!
– Zachscs
Apr 27 '18 at 21:25
5
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Given a DateTime object, how do I get an ISO 8601 date in string format?
...e correct. FYI the formatexception's message is: "A UTC DateTime is being converted to text in a format that is only correct for local times. This can happen when calling DateTime.ToString using the 'z' format specifier, which will include a local time zone offset in the output."
...
Create an empty list in python with certain size
...ate a list.
... s1.append(i)
... return s1
...
>>> print display()
[0, 1, 2, 3, 4, 5, 6, 7, 8]
List comprehension (Using the squares because for range you don't need to do all this, you can just return range(0,9) ):
>>> def display():
... return [x**2 for x in r...
Why are interface variables static and final by default?
Why are interface variables static and final by default in Java?
15 Answers
15
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Should I initialize variable within constructor or outside constructor [duplicate]
...
@Cromm yes, you can do that, but my point is that it is not a good practice, in my opinion: - if you have a logic, that is not related to actual construction, - if your logic can cause an exception, then you are opening a door to a potential usage of incomplete ...