我的应用程序不保存图像

Question

按下“保存”按钮后，我的应用程序崩溃了。我一直关注this tutorial。 LogCat显示错误“无法打开数据库文件

”

这是我的代码：

import android.provider.MediaStore; 
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;  

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");     
    }   
}