Saving and calling resources of third-party libraries of cocos2dx sqlite

Saving and calling resources of third-party libraries of cocos2dx sqlite

Sqlite3 is a simple front-end database. It is very convenient for games that store more data than before.

 

 

# Ifndef _ Sqlite3Test _ DataBaseHelper __

# Define _ Sqlite3Test _ DataBaseHelper __

 

# Include

 

# Include "sqlite3.h"

# Include

# Include

 

# Define DBNOTFOUND INT_MAX

 

Class DataBaseHelper

{// ===== Database operation handle ====

Public:

Static DataBaseHelper * sharedDataBaseHelper ();

~ DataBaseHelper ();

Int countForTable (const char * table );

Sqlite3_stmt * queryTable (const char * table, const char * fields, const char * condition, int offset = 0, int count = 0 );

Static void destroy ();

Void openSqliteInAndroid ();

 

Private:

DataBaseHelper ();

Static DataBaseHelper * dataBaseHelper;

Sqlite3 * database;

};

 

 

Template

Class DataBaseTable

{// Database table class

Protected:

DataBaseTable (){}

Virtual void parseStatement (sqlite3_stmt *) = 0;

Public:

Static T findDataById (int tid)

{// ===== Locate data by ID =======

Char condition [20];

Sprintf (condition, "id = % d", tid );

Sqlite3_stmt * stmt = DataBaseHelper: sharedDataBaseHelper ()-> queryTable (T: tableName (), NULL, condition, 0, 1 );

T t;

T. _ id = DBNOTFOUND;

If (sqlite3_step (stmt) = SQLITE_ROW ))

{

T. parseStatement (stmt );

}

Sqlite3_finalize (stmt );

Return t;

}

 

 

Static T findDataByTmp (const char * tmp, int tid)

{

Char condition [30];

Sprintf (condition, "% s = % d", tmp, tid); // based on conditions

Sqlite3_stmt * stmt = DataBaseHelper: sharedDataBaseHelper ()-> queryTable (T: tableName (), NULL, condition );

T t;

// T. _ id = DBNOTFOUND;

If (sqlite3_step (stmt) = SQLITE_ROW ))

{

T. parseStatement (stmt );

}

Sqlite3_finalize (stmt );

Return t;

}

 

 

 

Static T findDataByIdAndName (int tid, const char * name)

{// Locate the data by ID and name

Char condition [30];

Sprintf (condition, "id = % d and name = '% S'", tid, name );

Sqlite3_stmt * stmt = DataBaseHelper: sharedDataBaseHelper ()-> queryTable (T: tableName (), NULL, condition );

T t;

T. _ id = DBNOTFOUND;

If (sqlite3_step (stmt) = SQLITE_ROW ))

{

T. parseStatement (stmt );

}

Sqlite3_finalize (stmt );

Return t;

}

// The vector container template obtains the data.

Static std: vector FindData (const char * condition = NULL, int offset = 0, int count = 0)

{

Std: vector Res;

Sqlite3_stmt * stmt = DataBaseHelper: sharedDataBaseHelper ()-> queryTable (T: tableName (), NULL, condition );

While (sqlite3_step (stmt) = SQLITE_ROW ))

{

T t;

T. parseStatement (stmt );

Res. push_back (t );

}

Sqlite3_finalize (stmt );

Return res;

}

 

 

Static int count ()

{// Returns the size of the database table

Return DataBaseHelper: sharedDataBaseHelper ()-> countForTable (T: tableName ());

}

};

 

 

# Endif/* defined (_ Sqlite3Test _ DataBaseHelper __)*/

 

 

 

 

 

# Include "DataBaseHelper. h"

# Include

# Include "../CCFileUtils. h"

# Include

# Include

# Include "cocos2d. h"

 

 

Using namespace std;

Using namespace cocos2d;

 

DataBaseHelper * DataBaseHelper: dataBaseHelper = NULL;

 

DataBaseHelper: DataBaseHelper ()

{

# If (CC_TARGET_PLATFORM = CC_PLATFORM_IOS)

// If you need to open the corresponding database path on IOS platform

Std: string path = cocos2d: CCFileUtils: sharedFileUtils ()-> fullPathForFilename ("data/gameDataBean. db ");

CCLog ("------ % s -------------", path. c_str ());

Int res = sqlite3_open (path. c_str (), & database );

If (res! = SQLITE_ OK)

{

CCLog ("--> open db fail, error code is % d", res );

}

 

# Elif (CC_TARGET_PLATFORM = CC_PLATFORM_ANDROID)

OpenSqliteInAndroid ();

# Endif

 

}

 

Void DataBaseHelper: openSqliteInAndroid ()

{

// The android system cannot perform fopen operations on files under the assets Directory. Therefore, copy the files to/data/package name/files/and perform subsequent operations.

Std: string path = cocos2d: CCFileUtils: sharedFileUtils ()-> fullPathForFilename ("data/gameDataBean. db ");

Std: string writalePath = CCFileUtils: sharedFileUtils ()-> getWritablePath () + "gameDataBean. db ";

 

Unsigned long len = 0;

Unsigned char * data = NULL;

 

Data = CCFileUtils: sharedFileUtils ()-> getFileData (path. c_str (), "r", & len );

 

FILE * fp = fopen (writalePath. c_str (), "r ");

If (! Fp)

{

// If the database exists, do not copy it.

FILE * fp1 = fopen (writalePath. c_str (), "w + ");

Fwrite (data, sizeof (char), len, fp1 );

Fclose (fp1 );

} Else {

Fclose (fp );

}

 

 

Int res = sqlite3_open (writalePath. c_str (), & database );

If (res! = SQLITE_ OK)

{

CCLog ("--> open db fail, error code is % d", res );

}

}

 

DataBaseHelper * DataBaseHelper: sharedDataBaseHelper (){

If (! DataBaseHelper ){

DataBaseHelper = new DataBaseHelper ();

: Atexit (destroy );

}

Return dataBaseHelper;

}

 

Void DataBaseHelper: destroy ()

{

If (dataBaseHelper)

{

Delete dataBaseHelper;

}

}

 

DataBaseHelper ::~ DataBaseHelper ()

{

Sqlite3_close (database );

}

Int DataBaseHelper: countForTable (const char * table) {// number of returned tables

Char * SQL = (char *) malloc (strlen (table) + 22 );

Int count =-1;

Sprintf (SQL, "select count (*) from % s", table );

 

// The specific content of the sqlite3_stmt structure is not defined in sqlite. It is just an abstract type and is usually operated with its pointer during use,

// The sqlite3_stmt pointer is actually a pointer to the Vdbe struct.

Sqlite3_stmt * statement;

 

If (sqlite3_prepare_v2 (database, SQL,-1, & statement, NULL) = SQLITE_ OK) {// sqlite3_prepare_v2 query database interface

If (sqlite3_step (statement) = SQLITE_ROW)

{

Count = sqlite3_column_int (statement, 0 );

}

}

Free (SQL );

Return count;

}

 

// Query the table

Sqlite3_stmt * DataBaseHelper: queryTable (const char * table, const char * fields, const char * condition, int offset, int count)

{

String SQL = string ("select ");

If (fields ){

SQL. append (fields );

} Else {

SQL. append ("*");

}

SQL. append ("from ");

SQL. append (table );

If (condition ){

SQL. append ("where ");

SQL. append (condition );

}

 

If (count)

{

SQL. append ("limit ");

Char tmp [20];

Sprintf (tmp, "% d, % d", offset, count );

SQL. append (tmp );

}

SQL. append (";");

// Sqlite3_stmt it is an internal data structure that has resolved SQL statements and marked records by sqlite itself.

Sqlite3_stmt * statement;

 

If (sqlite3_prepare_v2 (database, SQL. c_str (),-1, & statement, NULL) = SQLITE_ OK ){

Return statement;

}

Return NULL;

}