Android study notes

The following 4 animation effects are provided in android:  

1. AlphaAnimation transparency animation effect  

2, ScaleAnimation zoom animation effect  

3, TranslateAnimation displacement animation effect  

4, RotateAnimation Rotation animation effect 

 

Android's NetworkOnMainThreadException exception

http://blog.csdn.net/mad1989/article/details/25964495

 

 

query

SQLiteDatabase dbInstance;

Cursor cursor = dbInstance.query(String table,String []Columns, String selection, String[]selectionArgs, String having, string 　orderBy);

 

table: table name, cannot be null

columns: The name of the column to be queried, which can be multiple or null, which means query all columns

selection: query conditions, such as id=? and name=? can be null

selectionArgs: Assign a value to the query condition, a question mark corresponds to a value, can be null in order

having: syntax have, can be null

orderBy: syntax, sort by xx, can be null

 

Android layout and image usage specifications 

http://blog.csdn.net/u011733020/article/details/51861682

 

In order to save memory, the Android system generally does not support the direct display of gif pictures. Even if you force the setting, only the first frame of the picture will be displayed.