SwiftUI Essentials

Views

• Basic building blocks of user interfaces.

• Define a piece of UI

• Prefer smaller, single-purpose view

• The entire SwiftUI framework is oriented around composition of small pieces: organize the code in the same way

• Each view is a Struct,therefore not inheriting anything

• Each view defines a small piece of UI, it doesn’t have to take care of everything

• Views are not persistent objects that we update over time using imperative event-based code.

• Views are defined declaratively as a function of their inputs.

Container Views

• Container views are declared as a composition of other views serving as their content.

• Those Content views are declared within a special kind of closure known as a @ViewBuilder.

For example, use the Form container to make things look like a normal settings screen

$bindings

• We use the leading dollar sign prefix to indicate that we should pass a binding in our state instead of just passing a read-only value.

• A binding is a kind of managed reference that allows one view to edit the state of another view.

Primitive Views

• Text

• Image

• Color

• Shape

• Spacer

• Divider

Controls

• Describe purpose, not visuals

• Adaptive and reusable

• Customizable

• Accessible out of the box

@environment property

• Connected to the environment value.

• We can use its value just like any other property.

• The environment is a great encapsulation for pushing data down through the view hierarchy.