using SQLCipher with android shipped sqlite database file

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无人共我
无人共我 2020-12-09 23:21

I have a database file reset in the assets file.

How can I use SQLCipher to encrypt the database in android?

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  •  忘掉有多难
    2020-12-09 23:47

    The following code excerpt can be used to create multiple tables in an SQLite Cipher database:

    Use these imports:

    import java.sql.SQLException;
    import net.sqlcipher.database.SQLiteDatabase;
    import net.sqlcipher.database.SQLiteOpenHelper;
    import android.content.ContentValues;  
    import android.content.Context;  
    import android.database.Cursor;  
    import android.util.Log;
    
    /** Helper to the database, manages versions and creation */
    
        public class DBAdapter extends SQLiteOpenHelper {
            private static final String DATABASE_NAME = "Test";
            private static final int DATABASE_VERSION = 1;
    
            // Table name
            public static final String TABLE_1 = "Table1";
            public static final String TABLE_2 = "Table2";
    
            // Column names for Table1 table
            static final String KEY_PASSWORD = "password";
            static final String KEY_USER = "user";
    
            // Column names for Table2 table
            static final String KEY_EVENT = "event";
            static final String KEY_USERNAME = "username";
    
    
            public DBAdapter(Context context) {
                super(context, DATABASE_NAME, null, DATABASE_VERSION);
            }
    
            @Override
            public void onCreate(SQLiteDatabase db) {
                String sql1 = "create table " + Table_1 + " (" + KEY_USER + " text primary key, " + KEY_PASSWORD + " text not null);";
                String sql2 = "create table " + Table_2 + " (" + KEY_EVENT + " text primary key, " + KEY_USERNAME + " text not null FOREIGN KEY(" + KEY_USERNAME + ") REFERENCES " + TABLE_1 + "(" + KEY_USER + "));";
                db.execSQL(sql1);
                db.execSQL(sql2);
            }
    
            @Override
            public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
                if (oldVersion >= newVersion){
                    return;
                }
    
                String sql = null;
                if (oldVersion == 1) 
                    sql = "alter table " + TABLE_1 + " add note text;";
                if (oldVersion == 2)
                    sql = "";
    
                Log.d("EventsData", "onUpgrade  : " + sql);
                if (sql != null)
                    db.execSQL(sql);
            } 
    
            public Cursor getAllUsers(String username, SQLiteDatabase db){
                return db.query(TABLE_1, ...);
            }
    
            public Cursor getAllEvents(String event, SQLiteDatabase db){
                return db.query(TABLE_2, ...);
            }
       }
    

    Now you can do all the CRUD methods for both tables. Just make sure that each method has an SQLiteDatabase as an argument as shown in the getAllUsers() method.

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