´«ÖDz¥¿Íjavaѧϰ 3gÊÖ»ú¿ª·¢Android 3
½ñÌìÊÇѧϰ
Android
µÄµÚÈýÌ죬½ñÌìÖ÷ҪѧÁË
Android
ÄÚÖõÄ
SQLite
Êý¾Ý¿â£¬Ñ§Ï°ÁËÔöɾ¸Ä²é¡£
SharedPreferences
½øÐÐÊý¾Ý´æ´¢
:
Android
ƽ̨¸øÎÒÃÇÌṩÁËÒ»¸ö
SharedPreferences
À࣬ËüÊÇÒ»¸öÇáÁ¿¼¶µÄ´æ´¢Àà£¬ÌØ±ðÊʺÏÓÃÓÚ±£´æÈí¼þÅäÖòÎÊý¡£Ê¹ÓÃ
SharedPreferences
±£´æÊý¾Ý£¬Æä±³ºóÊÇÓÃ
xml
Îļþ´æ·ÅÊý¾Ý£¬Îļþ´æ·ÅÔÚ
/data/data/<package
name>/shared_prefs
Ŀ¼Ï£º
SharedPreferences
±³ºóÊÇʹÓÃ
xml
Îļþ±£´æÊý¾Ý£¬
getSharedPreferences(name,mode)
·½·¨µÄµÚÒ»¸ö²ÎÊýÓÃÓÚÖ¸¶¨¸ÃÎļþµÄÃû³Æ£¬Ãû³Æ²»Óôøºó׺£¬ºó׺»áÓÉ
Android
×Ô¶¯¼ÓÉÏ¡£
ʹÓÃ
SQLite
Êý¾Ý¿â´æ´¢Êý¾Ý£º
SQLite
£¬
SQLite3
Ö§³Ö
NULL
¡¢
INTEGER
¡¢
REAL
£¨¸¡µãÊý×Ö£©¡¢
TEXT(
×Ö·û´®Îı¾
)
ºÍ
BLOB(
¶þ½øÖƶÔÏó
)
Êý¾ÝÀàÐÍ£¬ËäÈ»ËüÖ§³ÖµÄÀàÐÍÖ»ÓÐÎåÖÖ£¬µ«Êµ¼ÊÉÏ
sqlite3
Ò²½ÓÊÜ
varchar(n)
¡¢
char(n)
¡¢
decimal(p,s)
µÈÊý¾ÝÀàÐÍ£¬Ö»²»¹ýÔÚÔËËã»ò±£´æÊ±»áת³É¶ÔÓ¦µÄÎåÖÖÊý¾ÝÀàÐÍ¡£
SQLite
×î´óµÄÌØµãÊÇÄã¿ÉÒÔ±£´æÈκÎÀàÐ͵ÄÊý¾Ýµ½ÈκÎ×Ö¶ÎÖУ¬ÎÞÂÛÕâÁÐÉùÃ÷µÄÊý¾ÝÀàÐÍÊÇʲô¡£ÀýÈ磺¿ÉÒÔÔÚ
Integer
ÀàÐ͵Ä×Ö¶ÎÖдæ·Å×Ö·û´®£¬»òÕßÔÚ²¼¶ûÐÍ×Ö¶ÎÖдæ·Å¸¡µãÊý£¬»òÕßÔÚ×Ö·ûÐÍ×Ö¶ÎÖдæ·ÅÈÕÆÚÐÍÖµ¡£
µ«ÓÐÒ»ÖÖÇé¿öÀýÍ⣺¶¨ÒåΪ
INTEGER PRIMARY KEY
µÄ×Ö¶ÎÖ»ÄÜ´æ´¢
64
λÕûÊý£¬
µ±ÏòÕâÖÖ×Ö¶ÎÖб£´æ³ýÕûÊýÒÔÍâµÄÊý¾Ýʱ£¬½«»á²úÉú´íÎó¡£
SQLiteOpenHelper
¶ÔÊý¾Ý¿â½øÐа汾¹ÜÀí£º
ÎÒÃÇ¿ª·¢µÄÈí¼þ¿ÉÄܻᰲװÔڳɰÙÉÏǧ¸öÓû§µÄÊÖ»úÉÏ£¬Èç¹ûÓ¦ÓÃʹÓõ½ÁË
SQLite
Êý
¾Ý¿â£¬ÎÒÃDZØÐëÔÚÓû§³õ´ÎʹÓÃÈí¼þʱ´´½¨³öÓ¦ÓÃʹÓõ½µÄÊý¾Ý¿â±í½á¹¹¼°Ìí¼ÓһЩ³õʼ»¯¼Ç¼£¬ÁíÍâÔÚÈí¼þÉý¼¶µÄʱºò£¬Ò²ÐèÒª¶ÔÊý¾Ý±í½á¹¹½øÐиüС£ÄÇô£¬ÎÒ
ÃÇÈçºÎ²ÅÄÜʵÏÖÔÚÓû§³õ´ÎʹÓûòÉý¼¶Èí¼þʱ×Ô¶¯ÔÚÓû§µÄÊÖ»úÉÏ´´½¨³öÓ¦ÓÃÐèÒªµÄÊý¾Ý¿â±íÄØ£¿×ܲ»ÄÜÔÚÿ¸öÐèÒª°²×°´ËÈí¼þµÄÊÖ»úÉÏͨ¹ýÊÖ¹¤·½Ê½´´½¨Êý¾Ý¿â±í
°É£¿ÒòΪÕâÖÖÐèÇóÊÇÿ¸öÊý¾Ý¿âÓ¦Óö¼ÒªÃæÁٵģ¬ËùÒÔÔÚ
Android
ϵͳ£¬ÎªÎÒÃÇÌṩÁËÒ»¸öÃûΪ
SQLiteOpenHelper
µÄ³éÏóÀ࣬±ØÐë¼Ì³ÐËü²ÅÄÜʹÓã¬Ë
Ïà¹ØÎĵµ£º
Çë¿´ÏÂÃæÒ»Àý£º
public class TestAbstract {
int count;
public void operation(){
System.out.println("count = " + (++count));
}
}
public class Test extends TestAbstract {
public static void main(String[] args) {
Test test = new Test();
TestAbstract testAb = new TestAbstract();
testAb.operati ......
Java °´×Ö½Ú½ØÈ¡´øÓкº×ÖµÄ×Ö·û´®µÄ½â·¨£¬ÍøÉÏÓв»ÉÙÌÖÂÛ¡£ÕâÀïÎÒÒ²¸ø³öÒ»ÖÖÎÒ×Ô¼ºµÄ´¦Àí£¬»ù±¾ÔÀí»¹ÊÇͳ¼ÆÒª½ØÈ¡µÄ×Ö½ÚÊýÖÐÊDZíʾºº×ÖµÄ×Ö½ÚÊýÊÇ·ñÊÇżÊý¸ö£¬¼´ÊÇ·ñ¸ÕºÃ°üÀ¨ÁËÍêÕûµÄºº×Ö¡£
/**
* ±à³Ì£º±àдһ¸ö½ØÈ¡×Ö·û´®µÄº¯Êý£¬ÊäÈëΪһ¸ö×Ö·û´®ºÍ×Ö½ÚÊý£¬Êä³öΪ°´×Ö½Ú½ØÈ¡µÄ×Ö·û´®¡£ µ«ÊÇÒª±£Ö¤ºº×Ö²»±»½Ø°ë¸ ......
ÔÚËùÓÐ×é¼þ¶¼·Åµ½JFrameÖ®ºó£¬ÏÈsetSize()£¬È»ºóÔÙsetVisible() ¡£
ÉèÖÃÁË´°¿ÚµÄSize,²¼¾Ö¹ÜÀíÆ÷²ÅÄÜΪ¸÷¸ö×é¼þ°²ÅźÏÊʵÄλÖÃ,Ö®ºóÔÙ°Ñ´°ÌåÏÔʾ³öÀ´setVisible()£¬±ÈÈçÄ㻹²»ÖªµÀ³§·¿µÄ´óС£¬Õâʱ¾ÍÎÞ·¨¾ö¶¨É豸°²·ÅµÄλÖᣠ......
Integer n1 = new Integer(1);
Integer n2 = new Integer(1);
System.out.println(n1==n2); // false
Integer n1 = new Integer(3);
Integer n2 = new Integer(3);
System.out.println(n1.equals(n2)); //true
equals()ĬÈÏÒ²ÊDZȽÏreference£¬µ«ÊÇJavaÖеÄclass¸²¸ÇÁËequals()·½·¨ ......
ÎÒ½ñÌìѧϰÁËëÀÏʦ½²µÄ
svn cvs
֪ʶ£¬ÎÒ×öÁ˼òµ¥µÄ±Ê¼Ç£º
°æ±¾¿ØÖÆ
: °æ±¾¿ØÖÆ(Revision
control)ÊÇά»¤¹¤³ÌÀ¶Í¼µÄ±ê×¼×ö·¨£¬ÄÜ×·×Ù¹¤³ÌÀ¶Í¼´Óµ®ÉúÒ»Ö±µ½¶¨°¸µÄ¹ý³Ì¡£´ËÍ⣬°æ±¾¿ØÖÆÒ²ÊÇÒ»ÖÖÈíÌ幤³Ì¼¼ÇÉ£¬½è´ËÄÜÔÚÈíÌ忪·¢µÄ¹ý³ÌÖУ¬È·±£Óɲ»Í¬ÈËËù±à¼µÄͬһÎļþµµ°¸¶¼ÄܵÃÒÔͬ²½¡£
Subver ......