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How to trigger event when a variable's value is changed?
...ever the value of a field is going to change.
You can have your own EventHandler delegate or you can use the famous System.EventHandler delegate.
Usually there's a pattern for this:
Define a public event with an event handler delegate (that has an argument of type EventArgs).
Define a protected ...
Lambda capture as const reference?
...entifier
& identifier
this
The text only mention capture-by-copy and capture-by-reference and doesn't mention any sort of const-ness.
Feels like an oversight to me, but I haven't followed the standardization process very closely.
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How to create a drop-down list?
...
Best way to do it is:
Preview:
XML:
<Spinner
android:id="@+id/spinner1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@android:drawable/btn_dropdown"
android:spinnerMode="dropdown"/>
Java:
//get the sp...
JFrame in full screen Java
I will be doing a project soon and I will have to use full screen mode in it.
13 Answers
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Check if a row exists, otherwise insert
...erbook a flight, as it will insert a new row when there are 10 tickets max and you are booking 20.
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Difference between numeric, float and decimal in SQL Server
...d have better speed (up to 20x) and you should also consider when they got converted in .NET
What is the difference between Decimal, Float and Double in C#
Decimal vs Double Speed
SQL Server - .NET Data Type Mappings (From MSDN)
main source : MCTS Self-Paced Training Kit (Exam 70-433): Mi...
How do I time a method's execution in Java?
...l Duration.between(start, end).getSeconds(). Duration also has methods to convert to other time units, e.g. toMillis() which converts to milliseconds.
– Emil Lunde
May 29 '18 at 13:29
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Git interoperability with a Mercurial Repository
... I haven't tried this yet.
Finally, Tailor is a project that incrementally converts between a variety of different VCSs. It sounds like development of this won't be aggressively continued.
The first three of these approaches looked lightweight enough to persuade me to investigate. I needed to twea...
Computed / calculated / virtual / derived columns in PostgreSQL
... Postgres 11 generated columns are not supported - as defined in the SQL standard and implemented by some RDBMS including DB2, MySQL and Oracle. Nor the similar "computed columns" of SQL Server.
STORED generated columns are introduced with Postgres 12. Trivial example:
CREATE TABLE tbl (
int1 ...
Retain precision with double in Java
...of 11.4.
Now, a little explanation into why this is happening:
The float and double primitive types in Java are floating point numbers, where the number is stored as a binary representation of a fraction and a exponent.
More specifically, a double-precision floating point value such as the double...