Titlebook: Beginning iPhone Development with Swift 5; Exploring the iOS SD Wallace Wang Book 20195th edition Wallace Wang 2019 Swift.ios.iPhone.tvOS.w

anarchist

Image Analysis and Processing IIAlmost every app needs to display and accept data from the user. The simplest way to display data is through a label, but sometimes you need to display data and give the user a way to respond. In that case, you need to use an alert controller.

吸气

Xiaotian Yan,Fang Meng,Hongbin ZhaSince the iPhone and iPad come in different screen sizes, every iOS app needs to adapt to these different screen sizes depending on the type of iOS device it’s running on. To define the position and spacing of different user interface objects, you can use constraints.

opportune

Danilo Avola,Luigi Cinque,Giuseppe PlacidiOnly the simplest apps consist of a single view such as the Calculator app. Most apps usually need two or more views to display information. While you could create buttons and link them to different views, this can be a clumsy solution. A far better solution is to organize related views together.

绕着哥哥问

Martin Horn,Michael R. BertholdLike a Navigation Controller, a Tab Bar Controller also groups related view controllers together. The main difference is that a Navigation Controller can only display view controllers in sequential order. On the other hand, a Tab Bar Controller can jump to another view controller directly.

过于平凡

Elisa Ricci,Samuel Rota Bulò,Nicu SebeOne unique way to display the contents of two or more view controllers is through a Page View Controller, which lets users swipe left and right. Each swipe displays a different view controller like swiping through pages in an e-book.

向下五度才偏

Understanding iOS Programming,All programming involves the same task of writing commands for a computer to follow. To learn iOS programming, you need to learn three different skills:

连系

Using Common User Interface Objects,A user interface must display information to the user. In addition, a user interface must also allow the user to input data such as text or numbers. Finally, a user interface must allow the user to control the app. Displaying data, accepting data, and accepting commands form the heart of any user interface.

nautical

Steppers, Sliders, Progress Views, and Activity Indicator Views,Labels, text fields, and buttons are the three most common types of user interface objects, but they aren’t the only ones used to display information, allow input, and allow interaction from the user. Four other user interface objects that can display information, allow input, and allow interaction in different ways include

外表读作

Buttons, Switches, and Segmented Controls,Besides displaying data or letting users input data, the second most important purpose of a user interface is to allow users to control an app. At the simplest level, users can use buttons where each button represents a single command. Of course if you want to display multiple options, displaying multiple buttons on the screen can get crowded.

胎儿

Touch Gestures,Allowing the user to control an app through buttons, switches, or segmented controls is handy, but all of these controls take up space on the screen. To eliminate the need for extra objects on the user interface, your app can also detect and respond to touch gestures that allow direct manipulation of items displayed on the screen.