先从assets目录下读取文件到sd卡中
public static String CopySqliteFileFromRawToDatabases(String SqliteFileName) throws IOException {
// 第一次运行应用程序时，加载数据库到data/data/当前包的名称/database/<db_name>
File dir = new File("data/data/" + MyApplication.getContext().getPackageName() + "/databases");
if (!dir.exists() || !dir.isDirectory()) {
dir.mkdir();
}
File file = new File(dir, SqliteFileName);
InputStream inputStream = null;
OutputStream outputStream = null;
//通过IO流的方式，将assets目录下的数据库文件，写入到SD卡中。
if (!file.exists()) {
try {
file.createNewFile();
inputStream = MyApplication.getContext().getClass().getClassLoader().getResourceAsStream("assets/" + SqliteFileName);
outputStream = new FileOutputStream(file);
byte[] buffer = new byte[1024];
int len;
while ((len = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, len);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (outputStream != null) {
outputStream.flush();
outputStream.close();
}
if (inputStream != null) {
inputStream.close();
}
}
}
return file.getPath();
}
然后通过sql语句进行操控
/**
* 操作数据库进行查询
*
* @return
*/
private List<LoginBean> getProvincesFromSQLite() {
//数据库所在SD卡路径
String path = "data/data/" + MyApplication.getContext().getPackageName() + "/databases/linepower.sqlite";
SQLiteDatabase db = SQLiteDatabase.openDatabase(path, null, SQLiteDatabase.CONFLICT_NONE);
//查询数据
Cursor cursor = db.rawQuery("select description from exception values；", null);
List<LoginBean> list = new ArrayList<>();
LoginBean loginBean = null;
while (cursor.moveToNext()) {
String description = cursor.getString(cursor.getColumnIndex("description"));
loginBean = new LoginBean(description);
list.add(loginBean);
}
return list;
}
