Swift 4 NEW Tutorial-2 (Strings are Collections Again)

Prior to Swift 3, Strings are collection types, Now again in Swift 4 they are collections.

Swift 3 

-------------------------------------------------------------------------

var str = “Hello World!”

str.characters.count

str.characters.append(“appending….”)

-------------------------------------------------------------------------

Swift 4 

-------------------------------------------------------------------------

var str = “iOS Solves”

str.count        // 10

str.append(“ Blog”)      // iOS Solves Blog

-------------------------------------------------------------------------

Multiline strings :-

Swift 3

let name = “name1 \n name2 \n name3”

Output:

name1

name2

name3

Swift 4

Use 3 double quotes to specify it as a multiline string.

-------------------------------------------------------------------------

let name = “””

name1

name2

name3

“””

Output:

name1

name2

name3

-------------------------------------------------------------------------

Use spaces for indentation

-------------------------------------------------------------------------

let name = “””

  name1

  name2

  name3

“””

Output:

  name1

  name2

  name3

-------------------------------------------------------------------------

Hope this post is useful. Feel free to comment incase of any queries.

Swift 3 UITableView Dynamic cell height based on content

Let’s take an example of chat application, where chat bubbles dimensions vary dynamically based on the chatted text.

We can achieve this dynamic size of cell by calculating size of cell based on displaying text font, size and length.This is very tedious. We can achieve this simply using autolayouts and UITableView automatic dimension setting for row height.

First, Take your label and give below constraints. Constraint constants can be of your choice.

1. top
2. leading
3. trailing &
4. bottom

After that make label as multiline by giving number of Lines as 0 and Line Break as 'Word Wrap'.

Lines - 0

Line Break - Word Wrap

In the code, give the below settings to UITableView.

  

        self.tableViewRank.estimatedRowHeight = 500

      self.tableViewRank.rowHeight = UITableViewAutomaticDimension

That’s it. Now, Table view’s cells will be of dynamic height based on the label’s content.

Hope this post is useful. Feel free to comment incase of any queries.