Android保存图片到数据库，从数据库取图片的方法

//1.创建数据库

public class DBService extends SQLiteOpenHelper {
private final static int VERSION = 1;
private final static String DATABASE_NAME = "uniteqlauncher.db";

public DBService(Context context) {
    this(context, DATABASE_NAME, null, VERSION);
}

public DBService(Context context, String name, CursorFactory factory,
        int version) {
    super(context, name, factory, version);
}

@Override
public void onCreate(SQLiteDatabase db) {
    String sql = "CREATE TABLE [launcher]("
        + "[_id] INTEGER PRIMARY KEY AUTOINCREMENT,"
        + "[photo] BINARY)"; //保存为binary格式

    db.execSQL(sql);

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    if(newVersion > oldVersion){
        db.execSQL("DROP TABLE IF EXISTS[launcher]");
    } else {
        return;
    }
    onCreate(db);
}
}

//保存图片到数据库

public void savePhoto(Drawable appIcon, Context mContext){
 LayoutInflater mInflater = (LayoutInflater) mContext
 .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
 View v = inflater.inflate(R.layout.app_view, null);
 ImageView iv = (ImageView) v.findViewById(R.id.appicon);
 iv.setImageDrawable(appIcon);
 String INSERT_SQL = "INSERT INTO launcher(photo) values(?)";
 SQLiteDatabase db = mDBService.getWritableDatabase(); // 得到数据库
try {
 ByteArrayOutputStream baos = new ByteArrayOutputStream();
 ((BitmapDrawable) iv.getDrawable()).getBitmap().compress(
 CompressFormat.PNG, 100, baos);//压缩为PNG格式,100表示跟原图大小一样
Object[] args = new Object[] {baos.toByteArray() };
 db.execSQL(INSERT_SQL, args);
 baos.close();
 db.close();
 } catch (Exception e) {
 e.printStackTrace();
 }

}

 

//3.从数据库中取图片

public void getPhoto() {
 String SELECT_SQL = "SELECT photo FROM launcher";
 ImageView appIcon = (ImageView) v.findViewById(R.id.appicon);//v是我在类中定义的一个view对象，跟前面保存图片一样
byte[] photo = null;
 mDBService = new DBService(getContext());
 SQLiteDatabase db = mDBService.getReadableDatabase();
 Cursor mCursor = db.rawQuery(SELECT_SQL, null);
 if (mCursor != null) {
 if (mCursor.moveToFirst()) {//just need to query one time
 photo = mCursor.getBlob(mCursor.getColumnIndex("photo"));//取出图片
}
 }
if (mCursor != null) {
 mCursor.close();
 }
 db.close();

 ByteArrayInputStream bais = null;
if (photo != null) {
        bais = new ByteArrayInputStream(photo);
        appIcon.setImageDrawable(Drawable.createFromStream(bais, "photo"));//把图片设置到ImageView对象中
} 
    //appIcon显示的就是之前保存到数据库中的图片

}