A
UITableView
consists of a vertical list of
sections.
Each section consists of a vertical list of
UITableViewCells.
Each cell
contains a
line
of text
or an
image,
and maybe also an
accessory
such as a
checkmark
or a
disclosure
indicator
(shaped like a >).
To see the classic table,
open the Settings app on your iPhone.
To identify a cell in a table view we must specify its section number, and its row number within that section. Both numbers are zero-based. For example, the first cell in the first section is (0, 0). A table view that is not divided into sections is treated as one big section whose section number is 0.
An
IndexPath
object contains a pair of
Int
properties,
section
and
row,
giving the section number and row number of a
UITableViewCell
within a
UITableView.
For the time being, we will put only two numbers into an
NSIndexPath.
But
a later example
will exploit the fact that an
NSIndexPath
can hold more than two numbers.
When we write them, they are conventionally separated by periods:
10.20.30.40.50.
This series of numbers would be used by apps like the Settings app,
where we navigate from table to table to table.
As we drill deeper, the index path gets longer.
AppDelegate.
I wrote the entire demonstration in the
application(_:didFinishLaunchingWithOptions:)
method.
section = 20 row = 10 index 0 = 10 index 1 = 20 index 2 = 30 index 3 = 40 index 4 = 50 index 0 = 10 index 1 = 20 index 2 = 30 index 3 = 40 index 4 = 50 index 5 = 60