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How do I filter ForeignKey choices in a Django ModelForm?
...yset attribute. Depends on how your form is built. If you build an explicit form, you'll have fields named directly.
form.rate.queryset = Rate.objects.filter(company_id=the_company.id)
If you take the default ModelForm object, form.fields["rate"].queryset = ...
This is done explicitly in the ...
Android studio logcat nothing to show
...thing to show in the logcat. I used the terminal to run ./adb logcat and it works.
60 Answers
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How to find out element position in slice?
How does one determine the position of an element present in slice?
6 Answers
6
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How to remove non-alphanumeric characters?
... like you almost knew what you wanted to do already, you basically defined it as a regex.
preg_replace("/[^A-Za-z0-9 ]/", '', $string);
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Check whether a string is not null and not empty
...t get a null pointer exception from str.isEmpty() if str is null.
Beware, it's only available since Java SE 1.6. You have to check str.length() == 0 on previous versions.
To ignore whitespace as well:
if(str != null && !str.trim().isEmpty())
(since Java 11 str.trim().isEmpty() can be ...
Are trailing commas in arrays and objects part of the spec?
...ECMAScript 3
Section 11.1.5 in the ECMAScript 5 specification:
ObjectLiteral :
{ }
{ PropertyNameAndValueList }
{ PropertyNameAndValueList , }
So yes, it is part of the specification.
Update: Apparently this is new in ES5. In ES3 (page 41), the definition was just:
ObjectLitera...
How do I prevent the modification of a private field in a class?
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but do make sure it's a deep copy, not a shallow copy, of the data. For Strings it makes no difference, for other classes like Date where the content of the instance can be modified it can make a difference.
– jwenting
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Algorithm to detect overlapping periods [duplicate]
...n end date.
I need to detect if my first time period (A) is overlapping with another one(B/C).
In my case, if the start of B is equal to the end of A, they are not overlapping(the inverse too)
I found the following cases:
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Rails 4: assets not loading in production
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config.assets.precompile = ['*.js', '*.css', '*.css.erb']
This works with me. use following command to pre-compile assets
RAILS_ENV=production bundle exec rake assets:precompile
Best of luck!
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How can I get the latest JRE / JDK as a zip file rather than EXE or MSI installer? [closed]
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You can download a Java Portable from PortableApps.com. It will not change your system settings. You can put it on your USB stick.
UPD: for those who needs JDK there's an open-source project OpenJDK Portable
UPD2: there is also a JDK Portable (Oracle)
Some people might be inter...