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What is the relationship between Looper, Handler and MessageQueue in Android?
...: it reads and processes items from a MessageQueue. The Looper class is usually used in conjunction with a HandlerThread (a subclass of Thread).
A Handler is a utility class that facilitates interacting with a Looper—mainly by posting messages and Runnable objects to the thread's MessageQueue. Wh...
Preventing Laravel adding multiple records to a pivot table
...ems()->where('foreign_key', $foreignKey)->count() Which, well, actually performs an additional query too '^^ But I don't need to fetch and hydrate the whole collection unless I really need it.
– Silence
May 24 '15 at 13:57
...
How do I modify fields inside the new PostgreSQL JSON datatype?
...a":[null,{"b":[1,2,3]}]}'
For inserting into JSON array (while preserving all of the original values), the jsonb_insert() function can be used (in 9.6+; this function only, in this section):
SELECT jsonb_insert('{"a":[null,{"b":[1]}]}', '{a,1,b,0}', jsonb '2')
-- will yield jsonb '{"a":[null,{"b":[...
How to add pandas data to an existing csv file?
...
Thanks for the answer. This will allow me append new df on row-wise. But could you let me know how can I append the new df on column-wise?
– datanew
Nov 9 '18 at 21:30
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How to add local .jar file dependency to build.gradle file?
...
If you really need to take that .jar from a local directory,
Add next to your module gradle (Not the app gradle file):
repositories {
flatDir {
dirs 'libs'
}
}
dependencies {
implementation name: 'gson-2.2.4'
}
...
Can you organize imports for an entire project in eclipse with a keystroke?
Wouldn't it be nice to just do a keystroke and have eclipse organize all imports in all java classes instead of just the one you are looking at? Is this possible? Is there a keystroke for it?
...
How to find the statistical mode?
...max, and returns the first-appearing value of the set of modes. To return all modes, use this variant (from @digEmAll in the comments):
Modes <- function(x) {
ux <- unique(x)
tab <- tabulate(match(x, ux))
ux[tab == max(tab)]
}
...
How to set caret(cursor) position in contenteditable element (div)?
....setStart(el.childNodes[2], 5)
range.collapse(true)
sel.removeAllRanges()
sel.addRange(range)
}
<div id="editable" contenteditable="true">
text text text<br>text text text<br>text text text<br>
</div>
<button id="button" onclick="setCaret()">f...
Why can't enum's constructor access static fields?
...tatic fields and methods? This is perfectly valid with a class, but is not allowed with an enum.
5 Answers
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Array or List in Java. Which is faster?
I have to keep thousands of strings in memory to be accessed serially in Java. Should I store them in an array or should I use some kind of List ?
...