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What do I have to do to get Core Data to automatically migrate models?
...re to look.
In my AppDelegate I set-up the NSPersistentStoreCoordinator - and you need to add some options to this to tell it to handle auto-migrate:
NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithBool:YES], NSMigratePersistentStoresAutomaticallyOption,
[...
Do threads have a distinct heap?
... a common heap.
Each thread has a private stack, which it can quickly add and remove items from. This makes stack based memory fast, but if you use too much stack memory, as occurs in infinite recursion, you will get a stack overflow.
Since all threads share the same heap, access to the allocat...
Android mock location on device?
...ou have to enable mock locations in the development panel in your settings and add
<uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" />
to your manifest.
Now you can go in your code and create your own mock location provider and set the location of this provider...
How to convert local time string to UTC?
...igure out what the local timezone is, construct a timezone object from it, and manipulate and attach it to the naive datetime.
Finally, use datetime.astimezone() method to convert the datetime to UTC.
Source code, using local timezone "America/Los_Angeles", for the string "2001-2-3 10:11:12":
imp...
Standard way to embed version into python package?
Is there a standard way to associate version string with a python package in such way that I could do the following?
17 Ans...
Is there a difference between single and double quotes in Java?
Is there a difference between single and double quotes in Java?
4 Answers
4
...
vs
What is the difference between stdint.h and cstdint ?
3 Answers
3
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RE error: illegal byte sequence on Mac OS X
...for cross-compiling to iOS. The string has embedded double quotes. The command is:
7 Answers
...
Is there a JavaScript function that can pad a string to get to a determined length?
I am in need of a JavaScript function which can take a value and pad it to a given length (I need spaces, but anything would do). I found this:
...
Can you use if/else conditions in CSS?
...class="normal">Text</p>
<p class="active">Text</p>
and in your CSS file:
p.normal {
background-position : 150px 8px;
}
p.active {
background-position : 4px 8px;
}
That's the CSS way to do it.
Then there are CSS preprocessors like Sass. You can use conditionals there...