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Understanding colors on Android (six characters)
...ed as RGB or ARGB.
http://en.wikipedia.org/wiki/ARGB
In RGB you have two characters for every color (red, green, blue), and in ARGB you have two additional chars for the alpha channel.
So, if you have 8 characters, it's ARGB, with the first two characters specifying the alpha channel. If you remo...
What does the @ symbol represent in objective-c?
...
The @ character isn't used in C or C++ identifiers, so it's used to introduce Objective-C language keywords in a way that won't conflict with the other languages' keywords. This enables the "Objective" part of the language to free...
Build an iOS app without owning a mac? [closed]
...r virtual machine (the name is unimportant, I called it "Mac"). In "Type", select "Mac OS X" and in "Version" select "macOS 10.13 High Sierra (64 bit)" (the Mac version you will install on the virtual machine is actually Catalina, but VirtualBox doesn't have that option yet and it works just fine if...
how to check if a form is valid programmatically using jQuery Validation Plugin
... jQuery Validation plugin:
$("#form_id").valid();
Checks whether the selected form is valid or whether all selected
elements are valid. validate() needs to be called on the form before
checking it using this method.
Where the form with id='form_id' is a form that has already had .validat...
How do I perform the SQL Join equivalent in MongoDB?
...background as well, I would appreciate MongoDB taking a 'result set' (with selected returned fields) as input for a new query in one go, much like nested queries in SQL
– Stijn Sanders
Nov 26 '10 at 23:17
...
Insert the carriage return character in vim
...tored a file in Unix ( \n newlines). I need to insert the carriage return character ( U+000D aka \r ). When I try to paste it from the clipboard ( "+p ) or type it using Ctrl + Shift + u - 000d , the linefeed is inserted ( U+000A ).
...
MySQL - ORDER BY values within IN()
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SELECT id, name
FROM mytable
WHERE name IN ('B', 'A', 'D', 'E', 'C')
ORDER BY FIELD(name, 'B', 'A', 'D', 'E', 'C')
The FIELD function returns the position of the first string in the remaining list of strings.
However, it i...
Learning assembly [closed]
...y contents (in assembly language, hexadecimal or ASCII), make changes, and selectively execute COM, EXE and other file types.
It also has several subcommands which are used to access specific disk
sectors, I/O ports and memory addresses. MS-DOS Debug runs at a
16-bit process level and therefor...
How to find a table having a specific column in postgresql
...
you can query system catalogs:
select c.relname
from pg_class as c
inner join pg_attribute as a on a.attrelid = c.oid
where a.attname = <column name> and c.relkind = 'r'
sql fiddle demo
...
Why is using the rails default_scope often recommend against?
...ate) posts. So far so good.
2.1.1 :001 > Post.all
Post Load (0.2ms) SELECT "posts".* FROM "posts" WHERE "posts"."published" = 't'
Well this is pretty much what we expect. Now lets try:
2.1.1 :004 > Post.new
=> #<Post id: nil, title: nil, published: true, created_at: nil, update...