Good idea. How does this read?
Old version:
The code uses ‘this’ as the receiver, so the Sudoku class needs
to implement the OnClickListener interface and define a
method called onClick: (footnote: We could have used an
anonymous inner class to handle clicks, but according to the
Android developers, every new inner class takes up an extra
1KB of memory.)
New version:
The setOnClickListener method needs to be passed
an object that implements the OnClickListener Java interface.
We’re passing it the ‘this’ variable so we had better make
the current class (Sudoku) implement that interface or we’ll get
a compiler error. OnClickListener has one method in it called
onClick so we have to add that method to our class as well:
(footnote: If you’re a Java expert you may be wondering why we
didn’t use an anonymous inner class to handle the clicks.
You could, but according to the Android developers, every
new inner class takes up an extra 1KB of memory.)