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How to save an activity state using save instance state?
..."MyString", "Welcome back to Android");
// etc.
}
The Bundle is essentially a way of storing a NVP ("Name-Value Pair") map, and it will get passed in to onCreate() and also onRestoreInstanceState() where you would then extract the values from activity like this:
@Override
public void onRestoreI...
Best way to implement Enums with Core Data
...to assign a type property to the entity? In other words, I have an entity called Item with an itemType property that I want to be bound to an enum, what is the best way of going about this.
...
Add a column with a default value to an existing table in SQL Server
...ed for Existing Records.
If your Column is NOT NULL, then it will automatically use the Default Value
for all Existing Records, whether you specify WITH VALUES or not.
How Inserts work with a Default-Constraint:
If you insert a Record into SomeTable and do not Specify SomeCol's value, then it...
map vs. hash_map in C++
...tied to that key.
map is implemented as a balanced binary search tree (usually a red/black tree).
An unordered_map should give slightly better performance for accessing known elements of the collection, but a map will have additional useful characteristics (e.g. it is stored in sorted order, which...
Fling gesture detection on grid layout
...vent e) {
return true;
}
}
}
Attach your gesture listener to all the views you add to the main layout;
// Do this for each view added to the grid
imageView.setOnClickListener(SelectFilterActivity.this);
imageView.setOnTouchListener(gestureListener);
Watch in awe as your overridden ...
How do I remove the file suffix and path portion from a path string in Bash?
...
This is probably the most flexible of all the answers posted, but I think the answers suggesting the basename and dirname commands deserve some attention as well. They may be just the trick if you don't need any other fancy pattern matching.
...
Cleaning `Inf` values from an R dataframe
...ption 1
Use the fact that a data.frame is a list of columns, then use do.call to recreate a data.frame.
do.call(data.frame,lapply(DT, function(x) replace(x, is.infinite(x),NA)))
Option 2 -- data.table
You could use data.table and set. This avoids some internal copying.
DT <- data.table(dat)...
How can I print the contents of a hash in Perl?
I keep printing my hash as # of buckets / # allocated.
How do I print the contents of my hash?
11 Answers
...
Setting the correct encoding when piping stdout in Python
...you must encode it yourself.
A rule of thumb is: Always use Unicode internally. Decode what you receive, and encode what you send.
# -*- coding: utf-8 -*-
print u"åäö".encode('utf-8')
Another didactic example is a Python program to convert between ISO-8859-1 and UTF-8, making everything upper...
Why are quaternions used for rotations?
... multiplication is much faster than 3x3 matrix multiplication).
Note that all of these representations of rotations are used in practice. Euler angles use the least memory; matrices use more memory but don't suffer from Gimbal lock and have nice analytical properties; and quaternions strike a nice ...