Android Training Course (43)

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Arity-1.3.3.jar file is a library for processing computing expressions, the main content is the relevant part of the compilation principle, such as lexical analysis/syntax analysis, calculation expressions and so on. Its source code is available at: http://code.google.com/p/arity /.

The res directory is the directory for storing resource files. The resource content mainly includes images, multilingual strings, and interface arrangement. In applications, images and strings are always displayed, especially on multilingual interfaces. Strings in different countries are also needed. Therefore, these images and resources are maintained independently to improve development efficiency and Software maintainability. At the same time, the screen sizes of different mobile phones are different, but the source code is the same, but the resource sizes are different and the layout is different. For such a requirement, you only need to modify the resources to perfectly solve the problem. To meet this requirement, android applications divide resources into different directories to facilitate reading different configurations.

This directory contains the following directories:

Drawable values-cs values-fr values-pl values-uk

Drawable-hdpi values-da values-it values-pt values-zh-rCN

Drawable-mdpi values-de values-ja values-pt-rPT values-zh-rTW

Layout-land values-el values-ko values-ru

Layout-port values-es values-nb values-sv

Values-es-rUS values-nl values-tr

 

The drawable, drawable-mdpi, and drawable-hdpi directories store Bitmap-related content for program display. In these directories, it is possible to save the image or the xml file that saves the description. Multiple directories are used to support different resolutions:

Differences between drawable-hdpi, drawable-mdpi, and drawable:

(1) The drawable-hdpi contains high-resolution images, such as WVGA (480x800) and FWVGA (480x854)

(2) drawable-mdpi stores medium-resolution images, such as HVGA (320x480)

(3) drawable stores low-resolution images, such as QVGA (240x320)

The system will find the corresponding images in these folders according to the machine resolution.

To be compatible with different screens on different platforms during program development, we recommend that you store images of different versions in different folders as needed.