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A Better Django Admin ManyToMany Field Widget
...lt models.ManyToManyField widget to be cumbersome to use. It's the HTML select element and if you have a lot of Objects of the "other" model then it's quite impractical to actually find the "other" Objects you want to associate with "this" Object. And if you have a lot of objects of the "other...
How to create a drop-down list?
...eated one.
dropdown.setAdapter(adapter);
Notes:
You can use a setOnItemSelectedListener with this.
You can add a strings list from xml
There is an appCompat version of this view.
More information:
This is the basics but there is more to be self taught with experimentation.
https://developer....
How to split last commit into two in Git
...do and unstage all of the changes from the last commit:
git reset HEAD^
Selectively stage the first round of changes:
git add -p
Commit:
git commit
Commit the rest of the changes:
git commit -a
(In either step, if you undid a commit that added a brand new file and want to add this to the...
What is a NullReferenceException, and how do I fix it?
... to find out where the reference is or isn't set, right-click its name and select "Find All References". You can then place a breakpoint at every found location and run your program with the debugger attached. Every time the debugger breaks on such a breakpoint, you need to determine whether you exp...
How to implement custom JsonConverter in JSON.NET to deserialize a List of base class objects?
...o match a divierd class based on the class given to the serilaizer
/// Selected class will be the first class to match all properties in the json object.
/// </summary>
public class KnownTypeConverter : JsonConverter
{
public override bool CanConvert(Type objectType)
...
Is there a rule-of-thumb for how to divide a dataset into training and validation sets?
...o training and validation (again, 80/20 is a fair split).
Subsample random selections of your training data, train the classifier with this, and record the performance on the validation set
Try a series of runs with different amounts of training data: randomly sample 20% of it, say, 10 times and obs...
Convert List into Comma-Separated String
...s before you Aggragate to string. So you can do something like this: list.Select(x => string.Format("{0}:{1}", x.Key, x.Value)).Aggregate((a, x) => a+ ", " + x);
– bets
Jul 20 '17 at 8:14
...
INNER JOIN vs LEFT JOIN performance in SQL Server
...(ID, Name) VALUES (4, 'Four')
INSERT #Test2 (ID, Name) VALUES (5, 'Five')
SELECT *
FROM #Test1 t1
INNER JOIN #Test2 t2
ON t2.Name = t1.Name
SELECT *
FROM #Test1 t1
LEFT JOIN #Test2 t2
ON t2.Name = t1.Name
DROP TABLE #Test1
DROP TABLE #Test2
If you run this and view the execution plan, you'll se...
How to use conditional breakpoint in Eclipse?
...t editor margin or in the Breakpoints
view in the Debug perspective, and select the breakpoint’s properties.
In the dialog box, check Enable Condition, and enter an arbitrary Java
condition, such as list.size()==0. Now, each time the breakpoint is
reached, the expression is evaluated in th...
Visual Studio: Make view code default
...
Right-click on a file and select "Open With..."
Select "CSharp Editor" and then click "Set as Default".
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