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Fatal error: unexpectedly found nil while unwrapping an Optional values [duplicate]
...delegate to acquire an already allocated cell, in lieu of allocating a new one.
That's determined by the exclamation mark after AnyObject:
AnyObject!
So, first thing to consider is, what is an "Implicitly Unwrapped Optional"?
The Swift Programming Language tells us:
Sometimes it is cle...
How can I ensure that a division of integers is always rounded up?
...swer right the first time - is to approach the problem carefully, solve it one step at a time, and use good engineering principles in doing so.
Start by reading the specification for what you're trying to replace. The specification for integer division clearly states:
The division rounds the resu...
Why are dashes preferred for CSS selectors / HTML attributes?
...m the DOM anyway, which makes the whole dot notation rather useless. Which one would you prefer?
var firstName = $('#first-name');
var firstName = document.querySelector('#first-name');
var firstName = document.forms[0].first_name;
I find the two first options much more preferable, especially sin...
AngularJS - Multiple ng-view in single template
...
You can have just one ng-view.
You can change its content in several ways: ng-include, ng-switch or mapping different controllers and templates through the routeProvider.
...
How to convert a NumPy array to PIL image applying matplotlib colormap
...
Quite a busy one-liner, but here it is:
First ensure your NumPy array, myarray, is normalised with the max value at 1.0.
Apply the colormap directly to myarray.
Rescale to the 0-255 range.
Convert to integers, using np.uint8().
Use Imag...
MySQL “Group By” and “Order By”
...clauses will only apply to the returned column value, not to the discarded ones.
IMPORTANT UPDATE
Selecting non-aggregate columns used to work in practice but should not be relied upon. Per the MySQL documentation "this is useful primarily when all values in each nonaggregated column not named in th...
How to add an integer to each element in a list?
...
and the correspondent lazy computed one: new_list = (x+1 for x in my_list)
– Eduardo Pignatelli
Sep 14 '18 at 13:27
...
What's the role of adapters in Android?
...lass ArrayAdapter<T> extends BaseAdapter implements Filterable {
// One of the constructors
public ArrayAdapter(Context context, int resource, int textViewResourceId, T[] objects) {
init(context, resource, textViewResourceId, Arrays.asList(objects));
}
void manyMoreMethods(){}
}
Lets...
Custom UITableViewCell from nib in Swift
...3. This example will use a single ViewController to load two .xib files -- one for a UITableView and one for the UITableCellView.
For this example you can drop a UITableView right into an empty TableNib.xib file. Inside, set the file's owner to your ViewController class and use an outlet to refer...
Mockito: InvalidUseOfMatchersException
...
doNothing().when(cmd).dnsCheck(HOST, any(InetAddressFactory.class))
uses one raw value and one matcher, when it's required to use either all raw values or all matchers. A correct version might read
doNothing().when(cmd).dnsCheck(eq(HOST), any(InetAddressFactory.class))
...