阅读并保存图像到SQLite数据库

Question

嘿家伙我正在从事android检索和保存图像从SQLite数据库。这里是我的代码== >>

 public class MainActivity extends Activity implements OnClickListener { 
      protected static TextView textView; 
      protected static ImageView image1, image2; 
      protected Button get_image, save_image, read_image; 
      private String selectedImagePath; 
      private static final int SELECT_PICTURE = 1; 
      String DB_NAME = Environment.getExternalStorageDirectory() + "/test.db"; 
       String TABLE_NAME = "mytable"; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 

     image1 = (ImageView) findViewById(R.id.imageView1); 
     image2 = (ImageView) findViewById(R.id.imageView2); 
     textView = (TextView) findViewById(R.id.textView1); 

     get_image = (Button) findViewById(R.id.get_image); 
     get_image.setOnClickListener(this); 

     save_image = (Button) findViewById(R.id.save_image); 
     save_image.setOnClickListener(this); 

     read_image = (Button) findViewById(R.id.read_image); 
     read_image.setOnClickListener(this); 

    } 

    public void onClick(View v) { 

     int id = v.getId(); 
     switch (id) { 

     case R.id.get_image: 
      Intent intent = new Intent(); 
      intent.setType("image/*"); 
      intent.setAction(Intent.ACTION_GET_CONTENT); 
      startActivityForResult(
        Intent.createChooser(intent, "Select Picture"), 
        SELECT_PICTURE); 
      break; 

     case R.id.save_image: 
      createTable(); 
      saveInDB(); 
      break; 

     case R.id.read_image: 
      readFromDB(); 
      break; 
     default: 
      break; 

     } 
    } 

    public void onActivityResult(int requestCode, int resultCode, Intent data) { 
     if (resultCode == RESULT_OK) { 
      if (requestCode == SELECT_PICTURE) { 
       Uri selectedImageUri = data.getData(); 
       selectedImagePath = getPath(selectedImageUri); 
       System.out.println("Image Path : " + selectedImagePath); 
       image1.setVisibility(View.VISIBLE); 
       image1.setImageURI(selectedImageUri); 
      } 
     } 
    } 

    @SuppressWarnings("deprecation") 
    public String getPath(Uri uri) { 
     String[] projection = { MediaStore.Images.Media.DATA }; 
     Cursor cursor = managedQuery(uri, projection, null, null, null); 
     int column_index = cursor 
       .getColumnIndexOrThrow(MediaStore.Images.Media.DATA); 
     cursor.moveToFirst(); 
     return cursor.getString(column_index); 
    } 

    void createTable() { 
     SQLiteDatabase myDb = openOrCreateDatabase(DB_NAME, 
       Context.MODE_PRIVATE, null); 
     String MySQL = "create table if not exists " 
       + TABLE_NAME 
       + " (_id INTEGER primary key autoincrement, name TEXT not null, image BLOB);"; 
     myDb.execSQL(MySQL); 
     myDb.close(); 
    } 

    void saveInDB() { 
     SQLiteDatabase myDb = openOrCreateDatabase(DB_NAME, 
       Context.MODE_PRIVATE, null); 
     byte[] byteImage1 = null; 
     String s = myDb.getPath(); 

     myDb.execSQL("delete from " + TABLE_NAME);   // clearing the table 
     ContentValues newValues = new ContentValues(); 
     String name = "CoderzHeaven"; 
     newValues.put("name", name); 
     try { 
      FileInputStream instream = new FileInputStream(selectedImagePath); 
      BufferedInputStream bif = new BufferedInputStream(instream); 
      byteImage1 = new byte[bif.available()]; 
      bif.read(byteImage1); 
      newValues.put("image", byteImage1); 
      long ret = myDb.insert(TABLE_NAME, null, newValues); 
      if (ret < 0) 
       textView.append("Error"); 
     } catch (IOException e) { 
      textView.append("Error Exception : " + e.getMessage()); 
     } 
     myDb.close(); 
     textView.append("\n Saving Details \n Name : " + name); 
     textView.append("\n Image Size : " + byteImage1.length + " KB"); 
     textView.append("\n Saved in DB : " + s + "\n"); 
     Toast.makeText(this.getBaseContext(), 
       "Image Saved in DB successfully.", Toast.LENGTH_SHORT).show(); 
    } 

    void readFromDB() { 
     byte[] byteImage2 = null; 
     SQLiteDatabase myDb; 
     myDb = openOrCreateDatabase(DB_NAME, Context.MODE_PRIVATE, null); 
     Cursor cur = myDb.query(TABLE_NAME, null, null, null, null, null, null); 
     cur.moveToFirst(); 
     while (cur.isAfterLast() == false) { 
      textView.append("\n Reading Details \n Name : " + cur.getString(1)); 
      cur.moveToNext(); 
     } 

     // /////Read data from blob field//////////////////// 
     cur.moveToFirst(); 
     byteImage2 = cur.getBlob(cur.getColumnIndex("image")); 
     setImage(byteImage2); 
     cur.close(); 
     myDb.close(); 
     Toast.makeText(this.getBaseContext(), 
       "Image read from DB successfully.", Toast.LENGTH_SHORT).show(); 
     Toast.makeText(this.getBaseContext(), 
       "If your image is big, please scrolldown to see the result.", 
       Toast.LENGTH_SHORT).show(); 
    } 

    void setImage(byte[] byteImage2) { 
     image2.setImageBitmap(BitmapFactory.decodeByteArray(byteImage2, 0, 
       byteImage2.length)); 
     textView.append("\n Image Size : " + byteImage2.length + " KB"); 
    } 

} 

我面临的问题是，当过我试图执行上面的代码，我不能够检索或/图像保存到SQLite数据库。我能够从图库中获取图像。我卡住了，请帮助我。

谢谢:)

Answer 1

我只更改了DB存储位置..它的工作原理。

尝试......

SQLiteDatabase myDB = MainActivity.this.openOrCreateDatabase("test.db",//your db file name 
      MainActivity.this.MODE_PRIVATE, null);