大约有 40,000 项符合查询结果（耗时：0.0883秒） [XML]
What is the difference between Strategy design pattern and State design pattern?
...ce to the context object that contains them. Strategies do not.
States are allowed to replace themselves (IE: to change the state of the context object to something else), while Strategies are not.
Strategies are passed to the context object as parameters, while States are created by the context obj...
Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...Pandas Index itself:
df3 = df3[~df3.index.duplicated(keep='first')]
While all the other methods work, the currently accepted answer is by far the least performant for the provided example. Furthermore, while the groupby method is only slightly less performant, I find the duplicated method to be mor...
MenuItemCompat.getActionView always returns null
...
Finally I found the solution.
Changing namespace of actionViewClass from android:actionViewClass to app:actionViewClass
Implementing android.support.v7.widget.SearchView.OnQueryTextListener interface for current activity.
Dir...
How to handle Objective-C protocols that contain properties?
...answered May 10 '09 at 5:46
Kendall Helmstetter GelnerKendall Helmstetter Gelner
72.5k2626 gold badges123123 silver badges146146 bronze badges
...
Min/Max of dates in an array?
...
_.min and _.max work on arrays of dates; use those if you're using Lodash or Underscore, and consider using Lodash (which provides many utility functions like these) if you're not already.
For example,
_.min([
new Date(...
Practicing BDD with python [closed]
... you RSpec-like expectations. Everything you can do with RSpec expectation API, should-dsl does too. You can grab the latestversion from Github.
SpecLoud helps you on running BDD-like unittests. You can install it by doing
pip install specloud
Ludibrio is a library for test doubles (Mocks, Stubs...
Why does one use dependency injection?
...e virtual functions and interfaces (although I do once in a blue moon) and all my configuration is magically serialized into a class using json.net (sometimes using an XML serializer).
...
Naming convention for unique constraint
...primary key and foreign key have commonly used and obvious conventions ( PK_Table and FK_Table_ReferencedTable , respectively). The IX_Table_Column naming for indexes is also fairly standard.
...
How to force a web browser NOT to cache images
...(date, place, title, description, links, etc.) and save it. On that form I allow the administrator to upload an image related to the event. On the HTML page displaying the form, I am also showing a preview of the picture uploaded (HTML img tag).
...
What are unit tests, integration tests, smoke tests, and regression tests?
...re we just check that when the system under test is invoked it returns normally and does not blow up.
Smoke testing is both an analogy with electronics, where the first test occurs when powering up a circuit (if it smokes, it's bad!)...
... and, apparently, with plumbing, where a system of pipes i...