blocks|key|220486|text|设置数据库的|type|unstyled|depth|inlineStyleRanges|entityRanges|data|220487|public+class+DatabaseHelper+extends+SQLiteOpenHelper+{
++++//+Database+Version
++++private+static+final+int+DATABASE_VERSION+=+1;

++++//+Database+Name
++++private+static+final+String+DATABASE_NAME+=+"database_name";

++++//+Table+Names
++++private+static+final+String+DB_TABLE+=+"table_image";

++++//+column+names
++++private+static+final+String+KEY_NAME+=+"image_name";
++++private+static+final+String+KEY_IMAGE+=+"image_data";

++++//+Table+create+statement
++++private+static+final+String+CREATE_TABLE_IMAGE+=+"CREATE+TABLE+"+%2B+DB_TABLE+%2B+"("%2B+
+++++++++++++++++++++++KEY_NAME+%2B+"+TEXT,"+%2B+
+++++++++++++++++++++++KEY_IMAGE+%2B+"+BLOB);";

++++public+DatabaseHelper(Context+context)+{
++++++++super(context,+DATABASE_NAME,+null,+DATABASE_VERSION);
++++}

++++@Override
++++public+void+onCreate(SQLiteDatabase+db)+{

++++++++//+creating+table
++++++++db.execSQL(CREATE_TABLE_IMAGE);
++++}

++++@Override
++++public+void+onUpgrade(SQLiteDatabase+db,+int+oldVersion,+int+newVersion)+{
++++++++//+on+upgrade+drop+older+tables
++++++++db.execSQL("DROP+TABLE+IF+EXISTS+"+%2B+DB_TABLE);

++++++++//+create+new+table
++++++++onCreate(db);
++++}
}|code-block|syntax|javascript|220488|数据库中的插入：|offset|length|style|BOLD|220489|public+void+addEntry(+String+name,+byte[]+image)+throws+SQLiteException{
++++SQLiteDatabase+database+=+this.getWritableDatabase();
++++ContentValues+cv+=+new++ContentValues();
++++cv.put(KEY_NAME,++++name);
++++cv.put(KEY_IMAGE,+++image);
++++database.insert(+DB_TABLE,+null,+cv+);
}|220490|检索数据的|220491|+byte[]+image+=+cursor.getBlob(1);|220492|备注：|220493|220494|在插入到数据库之前，你需要先将你的位图图像转换成字节数组，然后使用数据库查询来应用它。|ordered-list-item|220495|当你从数据库中检索时，你肯定有一个字节数组的图像，你需要做的是将字节数组转换回原始图像。因此，您必须使用BitmapFactory进行解码。|220496|220497|下面是一个实用类，我希望它能帮助你：|220498|public+class+DbBitmapUtility+{

++++//+convert+from+bitmap+to+byte+array
++++public+static+byte[]+getBytes(Bitmap+bitmap)+{
++++++++ByteArrayOutputStream+stream+=+new+ByteArrayOutputStream();
++++++++bitmap.compress(CompressFormat.PNG,+0,+stream);
++++++++return+stream.toByteArray();
++++}

++++//+convert+from+byte+array+to+bitmap
++++public+static+Bitmap+getImage(byte[]+image)+{
++++++++return+BitmapFactory.decodeByteArray(image,+0,+image.length);
++++}
}|220499|进一步阅读|220500|如果您不熟悉如何在数据库中插入和检索，请参阅此tutorial。|220501|entityMap|0|LINK|mutability|MUTABLE|url|http://mrbool.com/how-to-insert-data-into-a-sqlite-database-in-android/28895^0|0|0|0|8|0|0|0|4|0|0|0|3|0|0|0|17|0|0|1Y|0|0|0|I|0|0|0|5|0|0|W|N|8|0|0^^$0|@$1|2|3|4|5|6|7|1H|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|1I|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|1J|8|@$I|1K|J|1L|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|1M|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|1N|8|@$I|1O|J|1P|K|L]]|9|@]|A|$]]|$1|Q|3|R|5|D|7|1Q|8|@]|9|@]|A|$E|F]]|$1|S|3|T|5|6|7|1R|8|@$I|1S|J|1T|K|L]]|9|@]|A|$]]|$1|U|3|-4|5|6|7|1U|8|@]|9|@]|A|$]]|$1|V|3|W|5|X|7|1V|8|@$I|1W|J|1X|K|L]]|9|@]|A|$]]|$1|Y|3|Z|5|X|7|1Y|8|@$I|1Z|J|20|K|L]]|9|@]|A|$]]|$1|10|3|-4|5|6|7|21|8|@]|9|@]|A|$]]|$1|11|3|12|5|6|7|22|8|@$I|23|J|24|K|L]]|9|@]|A|$]]|$1|13|3|14|5|D|7|25|8|@]|9|@]|A|$E|F]]|$1|15|3|16|5|6|7|26|8|@$I|27|J|28|K|L]]|9|@]|A|$]]|$1|17|3|18|5|6|7|29|8|@$I|2A|J|2B|K|L]]|9|@$I|2C|J|2D|1|2E]]|A|$]]|$1|19|3|-4|5|6|7|2F|8|@]|9|@]|A|$]]]|1A|$1B|$5|1C|1D|1E|A|$1F|1G]]]]

Setting Up the database 

<pre><code>public class DatabaseHelper extends SQLiteOpenHelper {
 // Database Version
 private static final int DATABASE_VERSION = 1;

 // Database Name
 private static final String DATABASE_NAME = "database_name";

 // Table Names
 private static final String DB_TABLE = "table_image";

 // column names
 private static final String KEY_NAME = "image_name";
 private static final String KEY_IMAGE = "image_data";

 // Table create statement
 private static final String CREATE_TABLE_IMAGE = "CREATE TABLE " + DB_TABLE + "("+ 
 KEY_NAME + " TEXT," + 
 KEY_IMAGE + " BLOB);";

 public DatabaseHelper(Context context) {
 super(context, DATABASE_NAME, null, DATABASE_VERSION);
 }

 @Override
 public void onCreate(SQLiteDatabase db) {

 // creating table
 db.execSQL(CREATE_TABLE_IMAGE);
 }

 @Override
 public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
 // on upgrade drop older tables
 db.execSQL("DROP TABLE IF EXISTS " + DB_TABLE);

 // create new table
 onCreate(db);
 }
}
</code></pre>

Insert in the Database: 

<pre><code>public void addEntry( String name, byte[] image) throws SQLiteException{
 SQLiteDatabase database = this.getWritableDatabase();
 ContentValues cv = new ContentValues();
 cv.put(KEY_NAME, name);
 cv.put(KEY_IMAGE, image);
 database.insert( DB_TABLE, null, cv );
}
</code></pre>

Retrieving data: 

<pre><code> byte[] image = cursor.getBlob(1);
</code></pre>

Note: 

<ol>
<li>Before inserting into database, you need to convert your Bitmap image into byte array first then apply it using database query.</li>
<li>When retrieving from database, you certainly have a byte array of image, what you need to do is to convert byte array back to original image. So, you have to make use of BitmapFactory to decode.</li>
</ol>

Below is an Utility class which I hope could help you:

<pre><code>public class DbBitmapUtility {

 // convert from bitmap to byte array
 public static byte[] getBytes(Bitmap bitmap) {
 ByteArrayOutputStream stream = new ByteArrayOutputStream();
 bitmap.compress(CompressFormat.PNG, 0, stream);
 return stream.toByteArray();
 }

 // convert from byte array to bitmap
 public static Bitmap getImage(byte[] image) {
 return BitmapFactory.decodeByteArray(image, 0, image.length);
 }
}
</code></pre>

 Further reading 
If you are not familiar how to insert and retrieve into a database, go through this <a href="http://mrbool.com/how-to-insert-data-into-a-sqlite-database-in-android/28895" rel="noreferrer">tutorial</a>.

blocks|key|218748|text|如果你正在使用安卓的MediaStore数据库，下面是如何存储图片并在保存后显示它的方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|218749|在按钮上单击write+|218750|+Intent+in+=+new+Intent(Intent.ACTION_PICK,
++++++++++++++++++++android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
++++++++++++in.putExtra("crop",+"true");
++++++++++++in.putExtra("outputX",+100);
++++++++++++in.putExtra("outputY",+100);
++++++++++++in.putExtra("scale",+true);
++++++++++++in.putExtra("return-data",+true);

++++++++++++startActivityForResult(in,+1);|code-block|syntax|javascript|218751|然后在您的activity中执行此操作|offset|length|style|BOLD|218752|@Override
++++protected+void+onActivityResult(int+requestCode,+int+resultCode,+Intent+data)+{
++++++++//+TODO+Auto-generated+method+stub
++++++++super.onActivityResult(requestCode,+resultCode,+data);

++++++++if+(requestCode+==+1+&&+resultCode+==+RESULT_OK+&&+data+!=+null)+{

++++++++++++Bitmap+bmp+=+(Bitmap)+data.getExtras().get("data");

++++++++++++img.setImageBitmap(bmp);
++++++++++++btnadd.requestFocus();

++++++++++++ByteArrayOutputStream+baos+=+new+ByteArrayOutputStream();
++++++++++++bmp.compress(Bitmap.CompressFormat.JPEG,+100,+baos);
++++++++++++byte[]+b+=+baos.toByteArray();
++++++++++++String+encodedImageString+=+Base64.encodeToString(b,+Base64.DEFAULT);

++++++++++++byte[]+bytarray+=+Base64.decode(encodedImageString,+Base64.DEFAULT);
++++++++++++Bitmap+bmimage+=+BitmapFactory.decodeByteArray(bytarray,+0,
++++++++++++++++++++bytarray.length);

++++++++}

++++}|218753|entityMap^0|0|0|0|0|D|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|V|8|@$K|W|L|X|M|N]]|9|@]|A|$]]|$1|O|3|P|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

If you are working with Android's MediaStore database, here is how to store an image and then display it after it is saved.

on button click write this

<pre><code> Intent in = new Intent(Intent.ACTION_PICK,
 android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
 in.putExtra("crop", "true");
 in.putExtra("outputX", 100);
 in.putExtra("outputY", 100);
 in.putExtra("scale", true);
 in.putExtra("return-data", true);

 startActivityForResult(in, 1);
</code></pre>

then do this in your activity

<pre><code>@Override
 protected void onActivityResult(int requestCode, int resultCode, Intent data) {
 // TODO Auto-generated method stub
 super.onActivityResult(requestCode, resultCode, data);

 if (requestCode == 1 &amp;&amp; resultCode == RESULT_OK &amp;&amp; data != null) {

 Bitmap bmp = (Bitmap) data.getExtras().get("data");

 img.setImageBitmap(bmp);
 btnadd.requestFocus();

 ByteArrayOutputStream baos = new ByteArrayOutputStream();
 bmp.compress(Bitmap.CompressFormat.JPEG, 100, baos);
 byte[] b = baos.toByteArray();
 String encodedImageString = Base64.encodeToString(b, Base64.DEFAULT);

 byte[] bytarray = Base64.decode(encodedImageString, Base64.DEFAULT);
 Bitmap bmimage = BitmapFactory.decodeByteArray(bytarray, 0,
 bytarray.length);

 }

 }
</code></pre>

In my project I need to store an image into a sqlite database and also need to retrieve it to show in my android emulator. When I show it directly after decoding the encoded string, which I got from Java class using sockets, the image displays there. But when I store a byte array code of the string into the sqlite database with the datatype blob and then again retrieve it by using the <code>getblob()</code> function it contains a different value and this error occurs: 

<pre><code>JAVA.lang.NULLPointerException: Factory returns null.
</code></pre>

I need a suggestion to store a bitmap image into a sqlite database and also to retrieve it from the sqlite database.

How to store(bitmap image) and retrieve image from sqlite database in android?

数据库

在我的项目中，我需要将图像存储到sqlite数据库中，还需要检索它以显示在我的android模拟器中。当我在解码编码的字符串后直接显示它时，图像显示在那里。但是，当我使用数据类型blob将字符串的字节数组代码存储到sqlite数据库中，然后再次使用getblob()函数检索它时，它包含一个不同的值，并发生以下错误：JA...

问如何在android中存储(位图图像)和从sqlite数据库中检索图像？
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