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Android add placeholder text to EditText
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In Android Studio you can add Hint (Place holder) through GUI. First select EditText field on designer view. Then Click on Component Tree Left side of IDE (Normally it's there, but it may be there minimized) There you can see Properties of selected EditText. Find Hint field as below Image
T...
Is there a way to recover from an accidental “svn revert”?
...ou will find local history option, where you will find all the history for selected file, including all the operation you did with that file (update,commit, revert ).
Good luck,
Arkde
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Rails find record with zero has_many records associated [duplicate]
..._joins(:photos).where(photos: {id: nil})
which will result in SQL like:
SELECT cities.*
FROM cities LEFT OUTER JOIN photos ON photos.city_id = city.id
WHERE photos.id IS NULL
Using includes:
City.includes(:photos).where(photos: {id: nil})
will have the same result, but will result in much ug...
Select element based on multiple classes
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You mean two classes? "Chain" the selectors (no spaces between them):
.class1.class2 {
/* style here */
}
This selects all elements with class1 that also have class2.
In your case:
li.left.ui-class-selector {
}
Official documentation : CSS2 class ...
How do I select an element in jQuery by using a variable for the ID?
For example, the following selects a division with id="2":
6 Answers
6
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Remove columns from dataframe where ALL values are NA
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dplyr now has a select_if verb that may be helpful here:
library(dplyr)
temp <- data.frame(x = 1:5, y = c(1,2,NA,4, 5), z = rep(NA, 5))
not_all_na <- function(x) any(!is.na(x))
not_any_na <- function(x) all(!is.na(x))
> temp
...
What's the difference between IQueryable and IEnumerable
...to execute the entire query against the underlying data source (like using SELECT TOP 1 in SQL).
See:
The .NET Standard Query Operators
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foll...
@import vs #import - iOS 7
...box), then move it to the "Frameworks" group. It will save many developers from the cryptic "Linker error" messages.
You don't actually need to use the @import keyword. If you opt-in to using modules, all #import and #include directives are mapped to use @import automatically. That means that you do...
Any reason to clean up unused imports in Java, other than reducing clutter?
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One would be that if you remove the class referenced by the import from the classpath, you won't get a silly compiler error that served no purpose. And you won't get false positives when you perform a "where used" search.
Another (but this would be very specific in nature) would be if the u...
SQL Server Text type vs. varchar data type [closed]
...ts in your database
If you do not search on the value of the column
If you select this column rarely and do not join on it.
VARCHAR is good:
If you store little strings
If you search on the string value
If you always select it or use it in joins.
By selecting here I mean issuing any queries that ...