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尝试环境:
Android2.2(源码) SDK
android-ndk-r7
尝试在NDK下面使用C语言做Android的SQLite3数据库存储功能。做了如下尝试:
在Android的源代码中找到sqlite3.h和libsqlite.so拷贝到NDK的lib(D:\android\android-ndk-r7-linux\platforms\android-3\arch-arm\usr\lib)和include(D:\android\android-ndk-r7-linux\platforms\android-3\arch-arm\usr\include)目录下。
测试代码:
/* -- START -- */
/*
*代码借用:http://www.cnblogs.com/sardine/archive/2011/07/30/2121853.html
*/
#include
#include
static int _sql_callback(void * notused, int argc, char ** argv, char ** szColName)
{
int i;
for ( i=0; i < argc; i++ )
{
printf( "%s = %s\n", *szColName, argv == 0 ? "NUL" : *argv );
}
return 0;
}
int main()
{
const char * sSQL1 = "create table users(userid varchar(20) PRIMARY KEY,age int,regtime datetime);";
const char * sSQL2 = "insert into users values('guilh',29,'2009-7-16');";
const char * sSQL3 = "select * from users;";
sqlite3 * db = 0;
char * pErrMsg = 0;
int ret = 0;
const char* const dbname = "gtest.db";
//打开数据库,如果数据库不存在,会建立一个数据库
ret = sqlite3_open(dbname, &db);
if ( ret != SQLITE_OK )
{
printf("open error! : %s", sqlite3_errmsg(db));
return(1);
}
printf("open db OK!\n");
// 执行建表SQL
sqlite3_exec( db, sSQL1, 0, 0, &pErrMsg );
if ( ret != SQLITE_OK )
{
//fprintf(stderr, "SQL error: %s\n", pErrMsg);
printf("SQL error: %s\n", pErrMsg);
sqlite3_free(pErrMsg);
}
// 执行插入记录SQL
sqlite3_exec( db, sSQL2, 0, 0, &pErrMsg);
// 查询数据表
sqlite3_exec( db, sSQL3, _sql_callback, 0, &pErrMsg);
// 关闭数据库
sqlite3_close(db);
db = 0;
return 0;
}
Android.mk: Android的make文件
#### START ####
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)
#include $(LOCAL_PATH)/../config.mk
LOCAL_SRC_FILES:= test.cpp
LOCAL_LDLIBS := -lcutils -licuuc -licui18n -lutils -licudata -lsqlite
#LOCAL_PRELINK_MODULE := false
LOCAL_MODULE := sqlite3
include $(BUILD_EXECUTABLE)
### END ###
如果此时直接编译的话会有如下提示:
$ make APP=sqlite3
Android NDK: Building for application 'sqlite3'
Executable : sqlite3
D:/android/android-ndk-r7-linux/toolchains/arm-linux-androideabi-4.4.3/prebuilt/windows/bin/../lib/gcc/arm-linux-androideabi/4.4.3/http://www.cnblogs.com/http://www.cnblogs.com/arm-linux-androideabi/bin/ld.exe: warning: libicuuc.so, needed by ./platforms/android-3/arch-arm/usr/lib/libsqlite.so, not found (try using -rpath or -rpath-link)
D:/android/android-ndk-r7-linux/toolchains/arm-linux-androideabi-4.4.3/prebuilt/windows/bin/../lib/gcc/arm-linux-androideabi/4.4.3/http://www.cnblogs.com/http://www.cnblogs.com/arm-linux-androideabi/bin/ld.exe: warning: libicui18n.so, needed by ./platforms/android-3/arch-arm/usr/lib/libsqlite.so, not found (try using -rpath or -rpath-link)
D:/android/android-ndk-r7-linux/toolchains/arm-linux-androideabi-4.4.3/prebuilt/windows/bin/../lib/gcc/arm-linux-androideabi/4.4.3/http://www.cnblogs.com/http://www.cnblogs.com/arm-linux-androideabi/bin/ld.exe: warning: libutils.so, needed by ./platforms/android-3/arch-arm/usr/lib/libsqlite.so, not found (try using -rpath or -rpath-link)
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `ucol_getShortDefinitionString_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `ucol_close_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `utf32_to_utf8'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `ucol_open_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `unorm_next_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `u_isalpha_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `ucol_strcollIter_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `ucol_getSortKey_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `utf8_length_from_utf32'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `utf8_appendCharSafeBody_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `ucol_strcoll_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `utf8_length'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `uiter_setUTF8_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `u_toupper_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `u_strtok_r_4_2'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `utf32_at'
./platforms/android-3/arch-arm/usr/lib/libsqlite.so: undefined reference to `ucol_setAttribute_4_2'
collect2: ld returned 1 exit status
build/core/build-binary.mk:324: recipe for target `out/apps/sqlite3/armeabi/sqlite3' failed
make: *** [out/apps/sqlite3/armeabi/sqlite3] Error 1
按照上面提示,依次从目标环境(源码或是你手机中)拷贝libcutils.so libicuuc.so libicui18n.so libutils.so libicudata.so到NDK的lib目录(见上)下。
如果出现如下错误:
$ make APP=sqlite3
Android NDK: Building for application 'sqlite3'
Executable : sqlite3
./platforms/android-3/arch-arm/usr/lib/libcutils.so: undefined reference to `ioprio_set'
./platforms/android-3/arch-arm/usr/lib/libicuuc.so: undefined reference to `mbstowcs'
./platforms/android-3/arch-arm/usr/lib/libcutils.so: undefined reference to `ioprio_get'
./platforms/android-3/arch-arm/usr/lib/libicuuc.so: undefined reference to `wcstombs'
collect2: ld returned 1 exit status
build/core/build-binary.mk:324: recipe for target `out/apps/sqlite3/armeabi/sqlite3' failed
make: *** [out/apps/sqlite3/armeabi/sqlite3] Error 1
拷贝目标环境的libc.so替换掉你开发环境里面的。
###执行结果如下:
# ./sqlite3
./sqlite3
open db OK!
userid = guilh
userid = guilh
userid = guilh
生成的数据库如下:
![使用NDK开发SQLite3_第1张图片](http://img.e-com-net.com/image/info8/618f3e00ed6e41a4864651929bb5cafb.png)
整个测试项目源代码:SQLite3.rar
数据库里面的regtime不对,是应该sql语句里面的时间不对。改下就ok:
const char * sSQL2 = "insert into users values('guilh',29,'2012-12-30 00:00:00');";
函数在线列表:http://www.sqlite.org/c3ref/funclist.html
sqlite取表函数(推荐):
int sqlite3_get_table(
sqlite3 *db, /* An open database */
const char *zSql, /* SQL to be evaluated */
char ***pazResult, /* Results of the query */
int *pnRow, /* Number of result rows written here */
int *pnColumn, /* Number of result columns written here */
char **pzErrmsg /* Error msg written here */
);
void sqlite3_free_table(char **result);
API说明文件:http://www.sqlite.org/c3ref/free_table.html