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Unique BooleanField value in Django?
...what I've done is override the save method for the model and have it check if any other model has the flag already set (and turn it off).
class Character(models.Model):
name = models.CharField(max_length=255)
is_the_chosen_one = models.BooleanField()
def save(self, *args, **kwargs):
...
Android Gallery on Android 4.4 (KitKat) returns different URI for Intent.ACTION_GET_CONTENT
...
Try this:
if (Build.VERSION.SDK_INT <19){
Intent intent = new Intent();
intent.setType("image/jpeg");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, getResources().g...
How to check if type of a variable is string?
Is there a way to check if the type of a variable in python is a string , like:
20 Answers
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When is std::weak_ptr useful?
...d to keep those in memory, so you get rid of the strong pointer.
But what if that object is in use and some other code holds a strong pointer to it? If the cache gets rid of its only pointer to the object, it can never find it again. So the cache keeps a weak pointer to objects that it needs to fin...
How can I verify if one list is a subset of another?
I need to verify if a list is a subset of another - a boolean return is all I seek.
15 Answers
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How to check if current thread is not main thread
I need to check if the thread running a certain piece of code is the main (UI) thread or not. How can I achieve this?
9 Ans...
How to tell if browser/tab is active [duplicate]
I have a function that is called every second that I only want to run if the current page is in the foreground, i.e. the user hasn't minimized the browser or switched to another tab. It serves no purpose if the user isn't looking at it and is potentially CPU-intensive, so I don't want to just waste ...
Remove blank attributes from an Object in Javascript
... test3 : 3,
}
function clean(obj) {
for (var propName in obj) {
if (obj[propName] === null || obj[propName] === undefined) {
delete obj[propName];
}
}
}
clean(test);
If you're concerned about this property removal not running up object's proptype chain, you can also:
funct...
How to ignore xargs commands if stdin input is empty?
...
For GNU xargs, you can use the -r or --no-run-if-empty option:
--no-run-if-empty
-r If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extensi...
Understanding the basics of Git and GitHub [closed]
...ng with other people, but I don't collaborate with anybody so I don't know if this would be helpful for me.
3 Answers
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