移动开发Android中SQlite数据库存取Bitmap

package cn.com;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import cn.db.DBservice;
import cn.db.Photo;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;


public class MainActivity extends Activity {
    private Button mButton;
    private Bitmap mBitmap;
    private ImageView mImageView;
    private boolean isDownload=true;
    private boolean isSave=false;
    private boolean isLoadFromDB=false;
    private static final int DOWNLOAD_FINISH=88;
    private byte[] photoByte;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        mButton=(Button) findViewById(R.id.button);
        mButton.setOnClickListener(new ButtonOnClickListener());
        mImageView=(ImageView) findViewById(R.id.imageView);
    }
   
   private class ButtonOnClickListener implements View.OnClickListener{
public void onClick(View v) {
if (isDownload) {
new Thread(){
public void run() {
mBitmap=getBitmap("http://s12.sinaimg.cn/middle/4b181bd0gbf6cb07c2a1b&690");
handler.sendEmptyMessage(DOWNLOAD_FINISH);
}
}.start();
}
if (isSave) {
DBservice service=new DBservice(MainActivity.this);
Photo photo=new Photo(1,mBitmap);
service.save(photo,photoByte);
isLoadFromDB=true;
isSave=false;
mButton.setText("从数据库中加载bitmap");
mImageView.setImageBitmap(null);
return;
}
if (isLoadFromDB) {
DBservice service=new DBservice(MainActivity.this);
Photo photo=service.find(1);
mImageView.setImageBitmap(photo.getPhoto());
}
}
   }
   
   Handler handler=new Handler(){
    public void handleMessage(Message msg) {
    switch (msg.what) {
case DOWNLOAD_FINISH:
mImageView.setImageBitmap(mBitmap);
mButton.setText("保存图片至SQLite");
isDownload=false;
isSave=true;
break;
default:
break;
}
    };
   };
   
public Bitmap getBitmap(String imagePath) {
try {
URL imageUrl = new URL(imagePath);
HttpURLConnection connection = (HttpURLConnection) imageUrl.openConnection();
connection.setConnectTimeout(5000);
connection.setRequestMethod("POST");
if (connection.getResponseCode() == 200) {
InputStream inputStream = connection.getInputStream();
photoByte= readResource(inputStream);
Bitmap bitmap=BitmapFactory.decodeByteArray(photoByte, 0, photoByte.length);
return bitmap;
}
} catch (Exception e) {
}

return null;
};
   public byte[] readResource(InputStream inputStream){
  try {
  ByteArrayOutputStream outputStream=new ByteArrayOutputStream();
    byte [] buffer=new byte[1024];
    int len=0;
    while( (len=inputStream.read(buffer))!=-1){
      outputStream.write(buffer,0,len);
    }
    inputStream.close();
    outputStream.close();  
    return outputStream.toByteArray();
} catch (Exception e) {
}
    return null;
   }
}
DataBaseOpenHelper.java如下:
package cn.db;


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


public class DataBaseOpenHelper extends SQLiteOpenHelper {




public DataBaseOpenHelper(Context context) {
super(context, "testbold.db", null, 1);
}


@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("create table test(photoid integer primary key autoincrement,id ingeter(10),photo Blob(20))");
}


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

}


}


 


DBservice.java如下:
package cn.db;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;


public class DBservice {
private DataBaseOpenHelper openHelper;
public DBservice(Context context) {
openHelper=new DataBaseOpenHelper(context);
}


public void save(Photo photo,byte [] photoByte){
SQLiteDatabase db=openHelper.getWritableDatabase();
        db.execSQL("insert into test (id,photo) values(?,?)",new Object[]{photo.getId(),photoByte});
        db.close();
}


public Photo find(int i){
SQLiteDatabase db=openHelper.getWritableDatabase();
Cursor cursor=db.rawQuery("select * from test where photoid=?", new String[]{String.valueOf(i)});
while(cursor.moveToFirst()){
int photoid=cursor.getInt(cursor.getColumnIndex("photoid"));
byte[] photoByte=cursor.getBlob(cursor.getColumnIndex("photo"));          
Bitmap bitmap=BitmapFactory.decodeByteArray(photoByte, 0, photoByte.length); 
Photo photo=new Photo(photoid, bitmap);
return photo;
}
cursor.close();
db.close();
return null;
}

}


Photo.java如下:
package cn.db;


import android.graphics.Bitmap;


public class Photo {
private int id;
private Bitmap bitmap;


public Photo() {
}


public Photo(int id, Bitmap bitmap) {
super();
this.id = id;
this.bitmap = bitmap;
}


public int getId() {
return id;
}


public void setId(int id) {
this.id = id;
}


public Bitmap getPhoto() {
return bitmap;
}


public void setPhoto(Bitmap bitmap) {
this.bitmap = bitmap;
}


}


 




main.xml如下:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >


    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:text="下载图片"
     />
    <ImageView
        android:id="@+id/imageView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
     />


</RelativeLayout>


manifest.xml如下:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="cn.com"
    android:versionCode="1"
    android:versionName="1.0" >


    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="15" />


     <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" /> 
    
    <application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/title_activity_main" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />


                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>


</manifest>