Pop Up Toast
You can get the control object first in OnCreate
The package name of the/data/data/program/file read/write under this directory may become unreliable due to changes in the package name.
This can be an activity, or it can be a context
This.getfiledir (); data/data/Package Name/files
File
Shared
Use the API to dynamically acquire SD cards, and to determine if there is an SD card
The "mounted" status is found.
File sccardfile = Environment.getexternalstoragedirectory ();
Read and write SD card requires permission,
Get the remaining free space on the SD card
Get Cache Directory
Android Read and Write permissions issues
/data/data/Package Name/files/aaa.txt
Openfileoutput ("Aaa.txt", Context.)
Permission-related
1. Private files
2. Writable files
3. Readable files
4. Readable and writable files
Read other people's things can not be dynamically acquired, Roar
Sharedperference: Where to store it:
XML serialization and parsing
POM: A little analysis, can stop, use more
Dom: Read all to Memory
Sax: A little parsing, can't stop
Generating an XML file using the Pull parser
Write XML to Local
Parsing from native XML
Data storage and access, permissions under Android