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Error message “No exports were found that match the constraint contract name”
This morning I faced a problem while opening my Visual Studio solution, and when I tried to run it, it said:
26 Answers
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Checking if an object is null in C#
... List<Object>();
Even better: since it's a field, make it private. And if there's nothing preventing you, make it also readonly. Just good practice.
Aside
The correct way to check for nullity is if(data != null). This kind of check is ubiquitous for reference types; even Nullable<T> ...
Duplicate ID, tag null, or parent id with another fragment for com.google.android.gms.maps.MapFragme
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The answer Matt suggests works, but it cause the map to be recreated and redrawn, which isn't always desirable.
After lots of trial and error, I found a solution that works for me:
private static View view;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bund...
How to flip windows in vim? [duplicate]
...tate in a 'column' or 'row' of split windows, C-wC-r
The following commands can be used to change the window layout. For example,
when there are two vertically split windows, CTRL-W K will change that in
horizontally split windows. CTRL-W H does it the other way around.
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initialize a numpy array
Is there way to initialize a numpy array of a shape and add to it? I will explain what I need with a list example. If I want to create a list of objects generated in a loop, I can do:
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Update value of a nested dictionary of varying depth
...ight general idea, i.e. a recursive solution, but somewhat peculiar coding and at least one bug. I'd recommend, instead:
Python 2:
import collections
def update(d, u):
for k, v in u.iteritems():
if isinstance(v, collections.Mapping):
d[k] = update(d.get(k, {}), v)
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Visual Studio 2010 annoyingly opens documents in wrong MDI pane
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Did you perhaps use the "New Horizontal Tab Group" command to split #1 into #1 and #2, then move your errors window into that?
I would just try resetting the window layout and see if that fixes it.
First, Window -> Close All Documents
Then, Window -> Reset Window Layout
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How do I uninstall a Windows service if the files do not exist anymore?
...xe) included in the Resource Kit.
(included with Windows 7/8)
Open a Command Prompt and enter
sc delete <service-name>
Tool help snippet follows:
DESCRIPTION:
SC is a command line program used for communicating with the
NT Service Controller and services.
delete---------...
NullPointerException accessing views in onCreate()
...d-generated code.
The view is in the fragment layout (fragment_main.xml) and not in the activity layout (activity_main.xml). onCreate() is too early in the lifecycle to find it in the activity view hierarchy, and a null is returned. Invoking a method on null causes the NPE.
The preferred solution...
Position: absolute and parent height?
I have some containers and their children are only absolute / relatively positioned. How to set containers height so their children will be inside of them?
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