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Reflection There are two problems before analyzing the source code When a sub-thread uses Toast directly, it throws an exception "Can't create handler in thread that has not called Looper. prepare ()", and searches for "Looper" in the Toast class and cannot find it. Where was the exception thrown? Use Toa ...

Preface This article mainly introduces the UI Application, UI Windows and the start-up process of the program. Through this article, I believe that you will understand the iOS application start-up process and app application level knowledge better. UIApplication Brief introduction One of the main tasks of UI Application is to process use ...

origin Recently, when Symbol was used as a unique value, it was found that Symbol can't do the new operation, it can only be used as a function, and type errors will occur whenever new is used new Symbol() // error Uncaught TypeError: Symbol is not a constructor at new Symbol (<anonymous>) at <anonymous>:1:1 Regardless of t ...

Activity Manager Service Analysis (2) - Activity Management (Note: The source code is android-8.1) 0. Preface In the article Android Source Reading Analysis: Activity Manager Service Analysis (1) - Start Process In this paper, we analyzed how the Activity Manager Service was created and started, and the initialization opera ...

Tree structure and Java implementation CatalogPrefaceWhen referring to the data structure "tree", I believe that many people think of "binary tree" first. Indeed, as an important data structure, binary tree combines the advantages of arrays and chained lists and has many important applications. As we all know, arrays are ch ...

Network Communications Purpose of using the network Link multiple parties together for data transmission; Network programming is to allow software on different computers to transfer data, that is, inter-process communication. ip address The concept and function of ip address What is the IP address: some numbers like 192.168.1.1; ip address: use ...

Dead work Install MySQL on windows and Ubuntu. Specific installation steps can be queried by csdn forum. Command-line scripts Operation of database Connect to the database Note: The sql statement ends with a semicolon. mysql -uroot -p; Enter the password to enter the database. Exit the database qiut，exit，ctrl + d ...

Today, we will share with you how to download and install Pycharm locally. The specific tutorials are as follows: 1. Go to Pycharm's official website first, or enter the web address directly: http://www.jetbrains.com/pycharm/download/#section=windows , download the PyCharm installation package, select it according to your computer's operating ...

1. Familiar with window structure diagram: 2. Understanding PhoneWindow, DecorView, Windows Manager, ViewRootImpl and other keywords. 2.1 PhoneWindow Every Activity has an instance of a Windows object, which is actually PhoneWindow type, so it can be seen that PhoneWindow is a subclass of Windows. Knowledge: Every Activit ...

ActivityManagerService Activity Manager Service (AMS) is one of the three core functions of the Android kernel, and the other two are Windows Manager Service and View. Activity Manager Service manages four components. Android wants to obscure the role of process and replace it with the concept of component. Activity Manger Ser ...