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Scope function selectionAt present, there are let, run, with and apply   and   also five scope functions.The official document has a table to illustrate the differences between them:    To sum up, there are several differences:1. apply and also return context objects.2,let,run   And with return lambda results.3. The ref ...

preface Background tasks in Android include JobScheduler, Loader, Service and other schemes  ， The emergence of WorkManager is used to replace all the above Android background task schemes, providing a unified solution for background tasks and ensuring the consistency and stability of api. At the same time, Google also takes into account ...

Handler is an asynchronous callback mechanism provided in Android, which can also be understood as a message mechanism between threads. In order to avoid ANR, we usually put some time-consuming operations (such as network request, I/O operation, complex calculation, etc.) into the sub thread for execution. When the sub thread needs to modify th ...

1, Lambda introduction As mentioned above, it has been widely used in Java, but this Lambda expression was only supported in Java 8. In other programming languages (for example, Scala). This expression is one of the grammatical sugars. Fortunately, Kotlin has supported this syntax as soon as open source matures. The essence of Lambda exp ...

Learning and error correction process of ListView control for Android School experiment implementation: establish a ListView component in the program interface. The component is divided into four lines with three items in each line. It displays "Zhao Linnan 20; Qian jienan 24; sun hongnv 22; Li Chengnan 29" respectively. Click a line ...

When we open an app at random, the interface displayed in front of us is displayed by the layout or the layout containing controls layout     Layout is how to arrange the controls it contains. Common layouts include linear layout, RelativeLayout and. FrameLayout. Of course, there are other layouts that I rarely use in development. ...

Problem environment: 1. WeChat Developer Tools 1.05.2110290 (hereinafter referred to as "Tools") 2. True machine debugging version 1.0 (does not distinguish between IOS and Android) 3. WeChat's editor component for rich text input (including pictures, multiple formats, etc.) in your own projects The Editor interface effect is shown in ...

1. Enter a value and return its data type function type(para) { return Object.prototype.toString.call(para) } Copy code 2. Array de duplication function unique1(arr) { return [...new Set(arr)] } function unique2(arr) { var obj = {}; return arr.filter(ele => { if (!obj[ele]) { ob ...

This is the second MAD Skills series on navigation. This is the third article in the navigation component series. If you want to review the content published in the past, please refer to the following link: Overview of navigation componentsNavigate to the dialog boxUse SafeArgs when navigating in an appUse deep link navigationBuild your firs ...

brief introduction NE, the full name of Native Exception, in Android, mainly refers to exceptions in native programs or natvie libraries running in user space. NE problems usually lead to program collapse, resulting in unstable functional modules. Common types of NE problems The following describes several common Native Crash situations: ...