如何在Sqlite数据库中插入所选图像？

Question

我的代码没有在数据库中插入图片。如何在数据库中插入所选图像，并检索它？我正在学习本教程：

  

http://vimaltuts.com/android-tutorial-for-beginners/android-sqlite-database-example

下面的代码需要对所选图像插入数据库进行哪些修改？

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

   public class AddEditCountry extends Activity {

 private long rowID; 
 private EditText nameEt;
 private EditText capEt;
 private EditText codeEt;

 private EditText Donedate;
 private EditText Notes;
 private EditText Person;
 private  ImageView imageView1;
 Bitmap yourSelectedImage;



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

      nameEt = (EditText) findViewById(R.id.Address);
      capEt = (EditText) findViewById(R.id.Stage);
      codeEt = (EditText) findViewById(R.id.Dueby);

      Donedate = (EditText) findViewById(R.id.Donedate);

      Notes = (EditText) findViewById(R.id.Notes);
      Person = (EditText) findViewById(R.id.Person);

      imageView1 = (ImageView) findViewById(R.id.imageView1);
      Button Browse = (Button) findViewById(R.id.Browse);


      Browse.setOnClickListener(new View.OnClickListener() 
        {
            public void onClick(View v) 
            {               
                Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
                intent.setType("image/*");
                startActivityForResult(intent, 0);
            }
        });        



      Bundle extras = getIntent().getExtras(); 

      if (extras != null)
      {
         rowID = extras.getLong("row_id");
         nameEt.setText(extras.getString("name"));  
         capEt.setText(extras.getString("cap"));  
         codeEt.setText(extras.getString("code"));  
         Donedate.setText(extras.getString("Location"));  
         Notes.setText(extras.getString("Notes")); 
         Person.setText(extras.getString("Person")); 



      }


      Button saveButton =(Button) findViewById(R.id.saveBtn);
      saveButton.setOnClickListener(new OnClickListener() {

          public void onClick(View v) 
          {
             if (nameEt.getText().length() != 0)
             {
                AsyncTask<Object, Object, Object> saveContactTask = 
                   new AsyncTask<Object, Object, Object>() 
                   {
                      @Override
                      protected Object doInBackground(Object... params) 
                      {
                         saveContact();
                         return null;
                      }

                      @Override
                      protected void onPostExecute(Object result) 
                      {
                         finish();
                      }
                   }; 

                saveContactTask.execute((Object[]) null); 
             }

             else
             {
                AlertDialog.Builder alert = new  
 AlertDialog.Builder(AddEditCountry.this);
                alert.setTitle(R.string.errorTitle); 
                alert.setMessage(R.string.errorMessage);
                alert.setPositiveButton(R.string.errorButton, null); 
                alert.show();
             }
          } 
     });
   }



   private void saveContact() 
   {


    //   ByteArrayOutputStream outStr = new ByteArrayOutputStream();
    //   yourSelectedImage.compress(CompressFormat.PNG, 100, outStr);
    //   byte[] blob = outStr.toByteArray();





      DatabaseConnector dbConnector = new DatabaseConnector(this);

      if (getIntent().getExtras() == null)
      {
          dbConnector.insertContact(nameEt.getText().toString(),
                  capEt.getText().toString(),
                  codeEt.getText().toString(),
                  Donedate.getText().toString(),
                  Notes.getText().toString(),
                  Person.getText().toString()
                  //,blob

              );
      }
      else
      {
         dbConnector.updateContact(rowID,
            nameEt.getText().toString(),
            capEt.getText().toString(), 
            codeEt.getText().toString(), 
            Donedate.getText().toString(),
         Notes.getText().toString(),
          Person.getText().toString()
          //, blob


         );
      }
   }










   @Override
   protected void onActivityResult(int requestCode, int resultCode, Intent  
   imageReturnedIntent) {
       super.onActivityResult(requestCode, resultCode, imageReturnedIntent);

       switch(requestCode) {
       case 0:
           if(resultCode == RESULT_OK){
               Uri selectedImage = imageReturnedIntent.getData();
               String[] filePathColumn = {MediaStore.Images.Media.DATA};

               Cursor cursor = getContentResolver().query(selectedImage,  
  filePathColumn, null, null, null);
               cursor.moveToFirst();

               int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
               String filePath = cursor.getString(columnIndex); // file path  
  of selected image
               cursor.close();
                       //  Convert file path into bitmap image using below  
 line.
               yourSelectedImage = BitmapFactory.decodeFile(filePath);

                       // put  bitmapimage in your imageview
               imageView1.setImageBitmap(yourSelectedImage);
           }
       }
    }






        }










       import android.content.Context;
    import android.database.Cursor;
   import android.database.SQLException;
    import android.database.sqlite.SQLiteDatabase;


  public class DatabaseConnector {

private static final String DB_NAME = "WorldCountries";
private SQLiteDatabase database;
private DatabaseOpenHelper dbOpenHelper;

public DatabaseConnector(Context context) {
    dbOpenHelper = new DatabaseOpenHelper(context, DB_NAME, null, 1);
}

   public void open() throws SQLException 
   {
      //open database in reading/writing mode
      database = dbOpenHelper.getWritableDatabase();
   } 

   public void close() 
   {
      if (database != null)
         database.close();
   }       

   public void insertContact(String name, String cap, String code, String 
      LocationEd, String Notes, String Person)
           ///,byte[] blob) 
           {
              ContentValues newCon = new ContentValues();
              newCon.put("name", name);
              newCon.put("cap", cap);
              newCon.put("code", code);

              newCon.put("Location",LocationEd);
              newCon.put("Notes",Notes);
              newCon.put("Person",Person);
          //    newCon.put("Image", blob);

              open();
              database.insert("country", null, newCon);
              close();
           }


           public void updateContact(long id, String name, String 
    cap,String code,String LocationEd, String Notes, String Person)
                   //,byte[] blob) 
           {
              ContentValues editCon = new ContentValues();
              editCon.put("name", name);
              editCon.put("cap", cap);
              editCon.put("code", code);
              editCon.put("Location", LocationEd);
              editCon.put("Notes", Notes);
              editCon.put("Person", Person);
            //  editCon.put("Image", blob);

              open();
              database.update("country", editCon, "_id=" + id, null);
              close();
           }


           public Cursor getAllContacts() 
           {
              return database.query("country", new String[] {"_id",   
    "name"}, 
                 null, null, null, null, "name");
           }

           public Cursor getOneContact(long id) 
           {
              return database.query("country", null, "_id=" + id, null,   
   null, null, null);
           }

           public void deleteContact(long id) 
           {
              open(); 
              database.delete("country", "_id=" + id, null);
              close();
           }
   }















   import android.content.Context;
   import android.database.sqlite.SQLiteDatabase;
   import android.database.sqlite.SQLiteDatabase.CursorFactory;
   import android.database.sqlite.SQLiteOpenHelper;

  public class DatabaseOpenHelper extends SQLiteOpenHelper {

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

@Override
public void onCreate(SQLiteDatabase db) {
    String createQuery = "CREATE TABLE country (_id integer primary key    
 autoincrement,name text,cap text,code text,Location double,Notes text,Person 
  text,blob BLOB);";              
    db.execSQL(createQuery);    














}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

}

   }












       import java.io.ByteArrayInputStream;

   import android.app.Activity;
  import android.app.AlertDialog;
 import android.content.DialogInterface;
 import android.content.Intent;
 import android.database.Cursor;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.graphics.Canvas;
 import android.net.Uri;
 import android.os.AsyncTask;
 import android.os.Bundle;
 import android.provider.MediaStore;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
 import android.view.View;
 import android.widget.Button;
  import android.widget.ImageView;
 import android.widget.TextView;

 public class ViewCountry extends Activity {

   private long rowID;
   private TextView nameTv;
   private TextView capTv;
   private TextView codeTv; 


   private TextView Locationlb; 
   private TextView Noteslb; 
   private TextView Personlb; 

   byte[] byteImage2 = null;

   private  ImageView imageView2;
   Bitmap yourSelectedImage;


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

      setUpViews();
      Bundle extras = getIntent().getExtras();
      rowID = extras.getLong(CountryList.ROW_ID); 
   }

   private void setUpViews() {
       nameTv = (TextView) findViewById(R.id.nameText);
       capTv = (TextView) findViewById(R.id.capText);
       codeTv = (TextView) findViewById(R.id.codeText);

       Locationlb = (TextView) findViewById(R.id.Location_lbl);



       Noteslb = (TextView) findViewById(R.id.Notes_lbl);
       Personlb = (TextView) findViewById(R.id.Person_lbl);


       imageView2= (ImageView) findViewById(R.id.imageView2);
          Button Browse2 = (Button) findViewById(R.id.Browse2);






          Browse2.setOnClickListener(new View.OnClickListener() 
            {
                public void onClick(View v) 
                {               
                    Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
                    intent.setType("image/*");
                    startActivityForResult(intent, 0);
                }
            });        























   }

   @Override
   protected void onResume()
   {
      super.onResume();
      new LoadContacts().execute(rowID);
   } 

   private class LoadContacts extends AsyncTask<Long, Object, Cursor> 
   {
      DatabaseConnector dbConnector = new DatabaseConnector(ViewCountry.this);

      @Override
      protected Cursor doInBackground(Long... params)
      {
         dbConnector.open();
         return dbConnector.getOneContact(params[0]);
      } 

      @Override
      protected void onPostExecute(Cursor result)
      {
         super.onPostExecute(result);

         result.moveToFirst();
         // get the column index for each data item
         int nameIndex = result.getColumnIndex("name");
         int capIndex = result.getColumnIndex("cap");
         int codeIndex = result.getColumnIndex("code");

         int LocationIndex = result.getColumnIndex("Location");
         int NotesIndex = result.getColumnIndex("Notes");
         int PersonIndex = result.getColumnIndex("Person");

   //      byte[] blob = result.getBlob("image");
   //      byte[] data = result.getBlob(result.getColumnIndex("image"));
      //   byte[] blob    result.getColumnIndex(MyBaseColumn.MyTable.ImageField));






         nameTv.setText(result.getString(nameIndex));
         capTv.setText(result.getString(capIndex));
         codeTv.setText(result.getString(codeIndex));
         Locationlb.setText(result.getString(LocationIndex));


         Noteslb.setText(result.getString(NotesIndex));
         Personlb.setText(result.getString(PersonIndex));

    //     ByteArrayInputStream input = new ByteArrayInputStream(byteImage2);

    //     Bitmap bit = BitmapFactory.decodeStream(input);
     //    imageView2.setImageBitmap(bit);
       //  imageView2.setImageURI(byteImage2);

         imageView2.setImageBitmap(yourSelectedImage);



         result.close();
         dbConnector.close();
      }
   } 


   @Override
   public boolean onCreateOptionsMenu(Menu menu) 
   {
      super.onCreateOptionsMenu(menu);
      MenuInflater inflater = getMenuInflater();
      inflater.inflate(R.menu.view_country_menu, menu);
      return true;
   }

   @Override
   public boolean onOptionsItemSelected(MenuItem item) 
   {
      switch (item.getItemId())
      {
         case R.id.editItem:
            Intent addEditContact =
               new Intent(this, AddEditCountry.class);

            addEditContact.putExtra(CountryList.ROW_ID, rowID);
            addEditContact.putExtra("name", nameTv.getText());
            addEditContact.putExtra("cap", capTv.getText());
            addEditContact.putExtra("code", codeTv.getText());

            addEditContact.putExtra("Location", Locationlb.getText());


            addEditContact.putExtra("Notes", Noteslb.getText());

            addEditContact.putExtra("Person", Personlb.getText());


        //    addEditContact.putExtra("blob", yourSelectedImage);

            startActivity(addEditContact); 
            return true;

         case R.id.deleteItem:
            deleteContact();
            return true;

         default:
            return super.onOptionsItemSelected(item);
      } 
   }

   private void deleteContact()
   {

      AlertDialog.Builder alert = new AlertDialog.Builder(ViewCountry.this);

      alert.setTitle(R.string.confirmTitle); 
      alert.setMessage(R.string.confirmMessage); 

      alert.setPositiveButton(R.string.delete_btn,
         new DialogInterface.OnClickListener()
         {
            public void onClick(DialogInterface dialog, int button)
            {
               final DatabaseConnector dbConnector = 
                  new DatabaseConnector(ViewCountry.this);

               AsyncTask<Long, Object, Object> deleteTask =
                  new AsyncTask<Long, Object, Object>()
                  {
                     @Override
                     protected Object doInBackground(Long... params)
                     {
                        dbConnector.deleteContact(params[0]); 
                        return null;
                     } 

                     @Override
                     protected void onPostExecute(Object result)
                     {
                        finish(); 
                     }
                  };

               deleteTask.execute(new Long[] { rowID });               
            }
         }
      );

      alert.setNegativeButton(R.string.cancel_btn, null).show();
   }








   protected void onActivityResult(int requestCode, int resultCode, Intent  
   imageReturnedIntent) {
       super.onActivityResult(requestCode, resultCode, imageReturnedIntent);

       switch(requestCode) {
       case 0:
           if(resultCode == RESULT_OK){
               Uri selectedImage = imageReturnedIntent.getData();
               String[] filePathColumn = {MediaStore.Images.Media.DATA};

               Cursor cursor = getContentResolver().query(selectedImage,  
  filePathColumn, null, null, null);
               cursor.moveToFirst();

               int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
               String filePath = cursor.getString(columnIndex); // file path  
   of selected image
               cursor.close();
                       //  Convert file path into bitmap image using below  
   line.
               yourSelectedImage = BitmapFactory.decodeFile(filePath);

                       // put  bitmapimage in your imageview
               imageView2.setImageBitmap(yourSelectedImage);
           }
       }
    }







}

Answer 1

不要将图像放入数据库。将文件保留在文件系统（SD卡或内部存储器）上，并将其引用到数据库中。但是不要直接放置图像。

Answer 2

无需在数据库中放置二进制blob。数据库的主要目标是查询，即它组织数据，以便以后快速找到它。图像是一个字节序列，您将无法根据它来过滤您的查询，因此只需将图像存储在文件系统中，并可能采用一种约定，它将以行的ID命名。