How To Change Screen Resolution After Install Ubuntu In VirtualBox

After installing Ubuntu in VirtualBox and log in to the Ubuntu OS, I find the ubuntu os screen resolution is configured at 800*600, this is not a good screen resolution for usage. I want to change it to at least 1920*1080. After investigate I finally find the method to change it.

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What Is Decorator In Python With Example

Decorators can add new functions or restrictions to the decorated objects without modifying the original source code. There are many kinds of decorators, including function decorators and class decorators. The name of decorator is different in many programming languages. It embodies the decoration pattern in the design pattern and emphasizes the open and closed principle.

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How To Fix Unresolved Import Issues In Eclipse PyDev Project

When I use eclipse to open an existing PyDev project, I find an error message like Unresolved import: smtplib. This error means the python3 built-in library smtplib can not be found and imported in python source code now. This error is because the python interpreter is not configured correctly, now I will tell you how

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How To Use iOS UISegmentedControl In Swift Programmatically Example

This example will tell you how to add and use the iOS UISegmentedControl object both in the Main.storyboard visually and programmatically in swift source code. There are two UISegmentedControl objects on the app screen. The above one is added to the Main.storyboard visually, when click it’s item, it will display the item title or image

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How To Use UITextField And UITextView In Swift Programmatically Example

We have introduced how to use UITextField and UITextView in the article iOS UITextField And UITextView Swift Example. In that article, we use interface builder and storyboard to create the user interface, assign delegate protocol to the view controller, implement delegate methods to respond to user action ( for example: begin editing a text field,

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Swift Xcode 11 iOS 13 Scene Delegate Life Cycle Example

When you create an iOS 13 project in Xcode 11 use a single view app template, you will find Xcode 11 add a SceneDelegate.swift file automatically beside the AppDelegate.swift file. It defines a SceneDelegate class in the SceneDelegate.swift file, and this class takes over some UI life cycle functions which are implemented by AppDelegate class

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How To Fix Error Use Of Unresolved Identifier ‘RootViewController’ In Xcode Swift Project

When I develop an iOS project in Xcode, I create a custom class RootViewController in RootViewController.swift file, this class is a subclass of UIViewController. But during the development process, when I use this custom class to create an object in another swift file ( for example SceneDelegate.swift ), I meet an error which said Use

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How To Fix Error Could Not Find A Storyboard Named ‘Main’ In Bundle NSBundle In Xcode 11.0

When I follow the article How To Create A Swift App Without Storyboard to learn how to create an iOS app without using the storyboard, after I remove the Main.storyboard file and run it. I meet an error message like this Could not find a storyboard named ‘Main’ in bundle NSBundle.

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