Swift

I want to implement an effect that when the iOS app starts, it popup an alert dialog on the screen and displays some messages. But during the process, I meet an error message like below, and the alert dialog is not displayed as I want. This article will tell you how to fix this issue.

If you want to import objective-c class’s .h and .m file into the swift project, Xcode will create an Objective-C Bridging Header file in the swift project automatically. But sometimes you will find it does not create the objective-c bridging header file, so you need to create and configure it manually. This article will tell

When we define a swift function, we can provide function parameters to it, and each function parameter can have an external name and an internal name. External name is used by the caller to pass value to the parameter, internal name is used by the function body to get the parameter value. Below is a

Xcode project organizes project resource files use Asset Catalog. Each asset catalog can contain multiple asset sets such as app icon set, image set, color set, etc. When you create an Xcode project use one project template such as Single View App, it will create a default asset catalog file Assets.xcassets in the project files

Swift UIKit.UIFont class is used to specify the label text font. You can use a system built-in text font, or you can customize the text font by providing the font name and font size. This example will tell you how to specify system font or provide customize text font to swift label component. It will

UIKit.UILabel class is used to create a label in iOS swift source code programmatically. You can change label text, label text color, label background color, label border width, label border color by setting it’s properties. You can also change the label text alignment by change the UILabel object’s textAlignment property value t0 NSTextAlignment.left, NSTextAlignment.center or NSTextAlignment.right.

This example will show you how to implement animation for the UIView object in swift. It will tell you how to implement the below three swift UIView animations. The first uiview animation moves a red view from the screen top left to the bottom right use swift code. It is a spring animation. The second

A swift view can have subviews, the subview can have it’s own subview also. So you can implement a view tree in swift, all the subviews are saved in a subview array, later added subview will override previously added subview. This article will show you an example to tell you how to add, insert, move

When I develop an iOS example application use swift, I meet a strange situation. When I click the run button to start my iOS example, it runs well. My example iOS app has a button, so I click it to trigger a Touch Up Inside event for this button, but this action makes my iOS