A simple review of Android and a review of android

A simple review of Android and a review of android
The Android system allows applications to create private files that can only be accessed by themselves, and the files are stored in the internal memory of the device.


ScrollView
Drag a SeekBar
RatingBar


Android Architecture


Application: Calendar, Address Book, email client, browser
Application Framework:


Function library Android Runtime


Linux Kernel


Android SDK: it can be understood as an Android System Simulator on a computer. It is a development environment and can install the APK software.
SDK soft development kit is generally a collection of application software development tools used by software engineers for specific software packages, software frameworks, hardware platforms, and operating systems. You can install the Android simulator to run the APK software. (A set of environments and tools required for Android development ).




To add a view object to the current dialog box, follow these steps:
View view = LayoutInflater. from (this). inflate (R. layout. main, null );


Common android. util. Log methods include Log. v () Log. d () Log. I () Log. w () and Log. e (). Corresponds to VERBOSE, DEBUG, INFO, WARN, and ERROR according to the first letter.
1. the debugging color of Log. v is black, and any message will be output. Here v stands for verbose, which is usually used as Log. v ("","");
2. The output color of Log. d is blue and only the meaning of debug debugging is output. However, it outputs the upper-layer information, which can be selected through the Logcat tag of DDMS.
3. The output of Log. I is green. Generally, it indicates message information. It does not output information of Log. v and Log. d, but displays information of I, w, and e.
4. Log. w indicates orange. It can be seen as a warning of warning. Generally, we need to optimize the Android code and select it to output Log. e.
5. Log. e is red. You can think of an error. Here, only red error messages are displayed.


Advantages and disadvantages of Android
Advantage: the open-source feature is supported by many vendors.
The system is developing fast, and the UI of the interface is well optimized.
Disadvantages: Quick updates, version inconsistencies, and inconsistent user experience.