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MVVM in WPF - How to alert ViewModel of changes in Model… or should I?
...ke this:
// Attach EventHandler
PlayerModel.PropertyChanged += PlayerModel_PropertyChanged;
...
// When property gets changed in the Model, raise the PropertyChanged
// event of the ViewModel copy of the property
PlayerModel_PropertyChanged(object sender, PropertyChangedEventArgs e)
{
if (e....
How to create local notifications?
...thorizationOptionAlert)
completionHandler:^(BOOL granted, NSError * _Nullable error) {
if (!error) {
NSLog(@"request authorization succeeded!");
[self showAlert];
}
}];
-(void)showAlert {
UIAlertController *objAlertControlle...
What is the Python equivalent of static variables inside a function?
...e at the top instead of the bottom, you can create a decorator:
def static_vars(**kwargs):
def decorate(func):
for k in kwargs:
setattr(func, k, kwargs[k])
return func
return decorate
Then use the code like this:
@static_vars(counter=0)
def foo():
foo.coun...
Get the first element of each tuple in a list in Python [duplicate]
...
Use a list comprehension:
res_list = [x[0] for x in rows]
Below is a demonstration:
>>> rows = [(1, 2), (3, 4), (5, 6)]
>>> [x[0] for x in rows]
[1, 3, 5]
>>>
Alternately, you could use unpacking instead of x[0]:
res_li...
BLE协议—广播和扫描 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...广播方式的报文有4种，分别为可连接的非定向广播（ADV_IND）、可连接的定向广播（ADV_DIRECT_IND）、可扫描非定向广播（ADV_SCAN_IND）、不可连接的非定向广播（ADV_NONCONN_IND）
4种广播的使用场景各不相同
可连接的非定向广播（A...
What is the best way to ensure only one instance of a Bash script is running? [duplicate]
...e
### HEADER ###
LOCKFILE="/var/lock/`basename $0`"
LOCKFD=99
# PRIVATE
_lock() { flock -$1 $LOCKFD; }
_no_more_locking() { _lock u; _lock xn && rm -f $LOCKFILE; }
_prepare_locking() { eval "exec $LOCKFD>\"$LOCKFILE\""; trap _no_more_locking EXIT; }
# ON START
_prepare_l...
Are there any reasons to use private properties in C#?
... them if I need to cache a value and want to lazy load it.
private string _password;
private string Password
{
get
{
if (_password == null)
{
_password = CallExpensiveOperation();
}
return _password;
}
}
...
How do I pass parameters into a PHP script through a webpage?
...cript over the web) is using the query string and access them through the $_GET superglobal:
Go to http://yourdomain.com/path/to/script.php?argument1=arg1&argument2=arg2
... and access:
<?php
$argument1 = $_GET['argument1'];
$argument2 = $_GET['argument2'];
?>
If you want the script t...
Is it true that one should not use NSLog() on production code?
... line number to make it easier to track down log statements.
#define DEBUG_MODE
#ifdef DEBUG_MODE
#define DebugLog( s, ... ) NSLog( @"<%p %@:(%d)> %@", self, [[NSString stringWithUTF8String:__FILE__] lastPathComponent], __LINE__, [NSString stringWithFormat:(s), ##__VA_ARGS__] )
#else
...
JavaScript function similar to Python range()
...to xrange in Python2:
function range(low, high) {
return {
__iterator__: function() {
return {
next: function() {
if (low > high)
throw StopIteration;
return low++;
}
...