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Sqlite primary key on multiple columns
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@pratnala In standard SQL, yes. In SQLite, NULL is allowed in primary keys. This answer emphasizes that if you want more standard behavior, you need to add the NOT NULL yourself. My answer is just the very basic syntax for a multi-column primary key.
– B...
In absence of preprocessor macros, is there a way to define practical scheme specific flags at proje
... The simplest example is the DEBUG=1 macro that is defined by default for all Xcode projects in the default scheme for the Run build. One could query #ifdef DEBUG ... and make decisions in the code accordingly, even compiling out non-necessary code.
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How can I get a Dialog style activity window to fill the screen?
...tivity with the dialog theme set, and I want it to be full screen. I tried all sorts of things, even going through the WindowManager to expand the window to full width and height manually, but nothing works.
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ScrollIntoView() causing the whole page to move
...ou want to scroll, you'll need to change the scrollTop of each one individually, based on the offsetTops of the intervening elements. This should give you the fine-grained control to avoid the problem you're having.
EDIT: offsetTop isn't necessarily relative to the parent element - it's relative t...
How do I disable the resizable property of a textarea?
... elements:
textarea {
resize: none;
}
To disable it for some (but not all) textareas, there are a couple of options.
To disable a specific textarea with the name attribute set to foo (i.e., <textarea name="foo"></textarea>):
textarea[name=foo] {
resize: none;
}
Or, using an id...
Bootstrap: How do I identify the Bootstrap version?
I want to update Bootstrap on a site, but I don't know the installed version.
11 Answers
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Defining an abstract class without any abstract methods
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Of course.
Declaring a class abstract only means that you don't allow it to be instantiated on its own.
Declaring a method abstract means that subclasses have to provide an implementation for that method.
The two are separate concepts, though obviously you can't have an abstract method ...
What does gcc's ffast-math actually do?
...tside of IEEE standards, but I can't seem to find information on what is really happening when it's on. Can anyone please explain some of the details and maybe give a clear example of how something would change if the flag was on or off?
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Create a List of primitive int?
... add "int" into this list.
When you add int to this list, it is automatically boxed to Integer wrapper type. But it is a bad idea to use raw type lists, or for any generic type for that matter, in newer code.
I can add anything into this list.
Of course, that is the dis-advantage of using r...
Gson custom seralizer for one variable (of many) in an object using TypeAdapter
...a great question because it isolates something that should be easy but actually requires a lot of code.
To start off, write an abstract TypeAdapterFactory that gives you hooks to modify the outgoing data. This example uses a new API in Gson 2.2 called getDelegateAdapter() that allows you to look up...