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How to do SELECT COUNT(*) GROUP BY and ORDER BY in Django?
...rize this relationship for each book
in the QuerySet.
Per-object summaries can be generated using the annotate() clause.
When an annotate() clause is specified, each object in the QuerySet
will be annotated with the specified values.
The order by clause is self explanatory.
To summarize: you group ...
Git: How to remove file from historical commit?
... the steps briefly here:
git filter-branch --index-filter \
'git rm --cached --ignore-unmatch path/to/mylarge_50mb_file' \
--tag-name-filter cat -- --all
Like the rebasing option described before, filter-branch is rewriting operation. If you have published history, you'll have to --force ...
What is routes.IgnoreRoute(“{resource}.axd/{*pathInfo}”)
...
.axd files don't exist physically. ASP.NET uses URLs with .axd extensions (ScriptResource.axd and WebResource.axd) internally, and they are handled by an HttpHandler.
Therefore, you should keep this rule, to prevent ASP.NET MVC from trying to handle th...
Difference between document.addEventListener and window.addEventListener?
...mple, the "DOMContentLoaded" event is only on the document object.
So basically, you need to know which object receives the event you are interested in and use .addEventListener() on that particular object.
Here's an interesting chart that shows which types of objects create which types of events:...
Type of conditional expression cannot be determined because there is no implicit conversion between
...round this:
int? number = true ? (int?)5 : null;
Here we are still in the case where only one of x and y has a type. Note that null still does not have a type yet the compiler won't have any problem with this because (int?)5 and null are both implicitly convertible to int? (§6.1.4 and §6.1.5).
Th...
Infinite scrolling with React JS
...
Basically when scrolling you want to decide which elements are visible and then rerender to display only those elements, with a single spacer element on top and bottom to represent the offscreen elements.
Vjeux made a fiddle her...
Why does int num = Integer.getInteger(“123”) throw NullPointerException?
...nteger(String) doesn't do what you think it does
It returns null in this case
the assignment from Integer to int causes auto-unboxing
Since the Integer is null, NullPointerException is thrown
To parse (String) "123" to (int) 123, you can use e.g. int Integer.parseInt(String).
References
J...
Non-type template parameters
... the non-type template parameter should be a constant integral expression. Can someone shed light why is it so ?
4 Answers
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Android - Dynamically Add Views into View
... the view where you need it.
LayoutInflater vi = (LayoutInflater) getApplicationContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = vi.inflate(R.layout.your_layout, null);
// fill in any details dynamically here
TextView textView = (TextView) v.findViewById(R.id.a_text_view);
tex...
How do I enable TODO/FIXME/XXX task tags in Eclipse?
... the task list. Apparently this is something that is disabled by default because I have been using those tags for as long as I've been using Eclipse and I have never seen one of them appear in the task list. Can anyone indicate how to enable this feature? I see no preferences option anywhere that sa...