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How to correctly save instance state of Fragments in back stack?
...
This is not related to question, onSaveInstance is not called when fragment is putted to backstack
– Tadas Valaitis
Jan 7 '15 at 10:14
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Dictionaries and default values
...collections import defaultdict
a = defaultdict(lambda: "default", key="some_value")
a["blabla"] => "default"
a["key"] => "some_value"
You can pass any ordinary function instead of lambda:
from collections import defaultdict
def a():
return 4
b = defaultdict(a, key="some_value")
b['absent...
Differences between socket.io and websockets
...ds can i conclude that the following statement is wrong? Socket.IO is actually more than a layer over WebSockets.
– Pulak Kanti Bhattacharyya
Aug 9 '14 at 15:18
3
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Python Pandas merge only certain columns
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You can use .loc to select the specific columns with all rows and then pull that. An example is below:
pandas.merge(dataframe1, dataframe2.iloc[:, [0:5]], how='left', on='key')
In this example, you are merging dataframe1 and dataframe2. You have chosen to do an outer left jo...
Flatten an Array of Arrays in Swift
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Just to state this more generally, flatMap is available as of Swift 1.2.
– Mick MacCallum
Apr 24 '15 at 4:56
3
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How to test android referral tracking?
...ust run in a terminal:
adb shell
am broadcast -a com.android.vending.INSTALL_REFERRER -n <your.package>/.<path.up.until.your.BroadcastReceiver> --es "referrer" "utm_source=test_source\&utm_medium=test_medium\&utm_term=test_term\&utm_content=test_content\&utm_campaign=te...
Storing SHA1 hash values in MySQL
...INARY(20) and CHAR(40).
CREATE TABLE `binary` (
`id` int unsigned auto_increment primary key,
`password` binary(20) not null
);
CREATE TABLE `char` (
`id` int unsigned auto_increment primary key,
`password` char(40) not null
);
With million of records binary(20) takes 44.56M, whil...
How to handle WndProc messages in WPF?
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Actually, as far as I understand such a thing is indeed possible in WPF using HwndSource and HwndSourceHook. See this thread on MSDN as an example. (Relevant code included below)
// 'this' is a Window
HwndSource source = HwndSou...
How to Copy Text to Clip Board in Android?
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In androidx it actually becomes ClipboardManager clipboard = getSystemService(getContext(), ClipboardManager.class);
– HoratioCain
Apr 25 '19 at 18:30
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How do I break out of a loop in Scala?
...nt) {
sum += i; if (sum < max) addTo(i+1,max)
}
addTo(0,1000)
(1c) Fall back to using a while loop
var sum = 0
var i = 0
while (i <= 1000 && sum <= 1000) { sum += 1; i += 1 }
(2) Throw an exception.
object AllDone extends Exception { }
var sum = 0
try {
for (i <- 0 to 1...