iOS, It is a mobile operating system developed by Apple Inc.
Features of iOS
The power of iOS felt with some of the following features provided as a part of the device.
- iCloud Facility
- In-App purchase
- Apple Pay
- Home Screen
- Notification Centre
- Game Center
- Camera integration
- Location services
- Notification Center
- Powerful APIs
- High end processor
- Email, contacts, web pages and messages etc.
iOS – UI Elements
UI elements are the visual elements that eventually we can see in our applications. Some of these elements respond to user interactions such as buttons, text fields and others are informative such as images, labels.
We can add UI elements both in code and with the help of interface builder. Depending on the need we can further use either one of them.
UI Specific Elements
|Sr.No.||UI Specific Elements|
|1||Text Fields: It is an UI element that enables the app to get user input eventually.|
|2||Input types – TextFields: We can set the type of input that user can give additionally by using the keyboard property of UITextField.|
|3||Buttons: It is used for handling user actions.|
|4||Label: It is used for displaying static content.|
|5||Toolbar: It is used if we want to manipulate something based on our current view.|
|6||Status Bar: It displays the key information of device.|
|7||Navigation Bar: It contains the navigation buttons of a navigation controller, which is a stack of view controllers hence can push and popped.|
|8||Tab bar: However, it generally used to switch between various subtasks, views or models within the same view.|
|9||Image View: It is used to display a simple image or sequence of images.|
|10||Scroll View: It is used to display content that is more than the area of screen.|
|11||Table View: It is used for displaying scrollable list of data in multiple rows and sections.|
|12||Split View: It is used for displaying two panes with master pane controlling the information on detail pane.|
|13||Text View: It is used for diplaying scrollable list of text information that is optionally editable.|
|14||View Transition: It especially explains the various view transitions between views.|
|15||Pickers: It is used for displaying for selecting a specific data from a list.|
|16||Switches: It is used as disable and enable for actions.|
|17||Sliders: It is used to allow users to make adjustments to a value or process throughout a range of allowed values.|
|18||Alerts: It is used to give important information to users.|
|19||Icons: It is an image representation used for an action or depict something related to the application.|
Views are the fundamentals of iOS application development, and because of this UIView is one of the most used object in the object library. The views are the basic building block of the iOS application, which renders the content within its bounds rectangle and also handles any interaction with the content.
UIViews are the fundamentals and the connection point of the iOS application with the user.
In iOS applications, whenever we need to display the single column containing vertically scrolling content, we use tableview. The tableview can display multiple records (divided into rows), which can also scroll vertically if needed. Thus each row of the tableview presents each record of the data source. For example, in the contact app, we display each contact name in the separate row of the tableview, and we get the details related to the contact on the click to that row.
When we add the collectionview to the application interface, iOS application responsibility to manage the data associated with the collectionview. CollectionView object works similar to the tableview since it gets the data from the DataSource object, which conforms to the UICollectionViewDataSource protocol.
The data associated with the collection view treated as the individual items which further grouped into the sections to represent into a grid layout on the iPhone screen. Moreover the UICollectionView used in most of the iOS applications, where we want the data to be horizontally scrollable.
Model View Controller
MVC is the most common and the easiest pattern to follow in the iOS application. Commonly it used beginner-level software architecture design pattern made with the following objects.
- The Model contains the things that used to handle the data of the application. It used to parse the request and then response with the server’s API. Such as things like persistence, model objects, parsers, managers, and networking code reside here.
- The View treated as the face of the application. The object such as UILabel and UITextField are the view objects that present the data on the screen. However, the view doesn’t contain any domain-specific logic.
- The controller used as the mediator between the Model and the view via the delegation pattern. Though the controller doesn’t need to know the concrete view it is working for. However, the controller contains the business logic to present the data, it parsed by the model and displayed by the view objects.