Android Development Series logs-(5)

1. Obtain network text
1. Java code
Create a URL object
Call openconnection () to obtain an httpurlconnection object.
Setconnectiontimeout ()
Get Response Code getresponsecode ()
Getinputstream ()
Read data
Convert to string
2. UI scrolling
Scrollview
Horizontalscrollview

2. Obtain network images
1. function implementation
It is very similar to the text, but after reading the data, it is converted into bitmap. bitmapfactory. decodebytearray ()
2. Cache
After reading data from the server, the data is cached locally.
The last modification time is included in the next request.
The server determines the modification time. If 200 or 304,304 is returned, the server reads the cache. If 200 is returned, the server data is updated and downloaded again.

Iii. JSON
1. What is JSON
JSON is also a way to carry data, similar to XML. The advantage is that it is small.
2. How to resolve
Create a jsonarray object using a string
Traverse the jsonarray object to obtain each jsonobject.
Get data from jsonobject


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