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How to store and retrieve bitmap in sharedPreferences in Android?

开发者 https://www.devze.com 2023-04-02 10:22 出处:网络
I am new in Android. I want to store my bitmap in sharedPreferences. Can anyone tell me how it will possible? Actually my requirements is, I fetch the image from gallery as well as take picture from c

I am new in Android. I want to store my bitmap in sharedPreferences. Can anyone tell me how it will possible? Actually my requirements is, I fetch the image from gallery as well as take picture from camera and I set that Bitmap in my ImageView. These all things wo开发者_运维知识库rk properly. But when I click on back button all ImageView will be empty.

So I want to store that Bitmaps throughout my application.

Can anyone help me? I am very much stuck on this.

Thanks.


Hey friends I got the solution of my problem here I post my code so that others can use this solution..

1). on button click - open camera for captureing image

ContentValues values = new ContentValues();  
values.put(MediaStore.Images.Media.TITLE, fileName);  
mCapturedImageURI = getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);  

Intent cameraIntent = new Intent("android.media.action.IMAGE_CAPTURE");
cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, mCapturedImageURI);  
startActivityForResult(cameraIntent, CAMERA_REQUEST);

2). on button cllick - open Gallery for select image

Intent galleryintent = new Intent(Intent.ACTION_GET_CONTENT);
galleryintent.setType("image/*");
startActivityForResult(galleryintent, IMAGE_PICK);

3). Static variables

private static final int CAMERA_REQUEST = 0; 
    private static final int IMAGE_PICK = 1;

4). onActivityResult

    protected void onActivityResult(int requestCode, int resultCode, Intent data) 
        {
            switch(requestCode) 
            { 
                case CAMERA_REQUEST:
                    if(resultCode == RESULT_OK)
                    {
                        String[] projection = { MediaStore.Images.Media.DATA}; 
                        Cursor cursor = managedQuery(mCapturedImageURI, projection, null, null, null); 
                        int column_index_data = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA); 
                        cursor.moveToFirst(); 
                        String capturedImageFilePath = cursor.getString(column_index_data);
                        Log.d("photos*******"," in camera take int  "+capturedImageFilePath);

                        Bitmap photo_camera = BitmapFactory.decodeFile(capturedImageFilePath, options);

                        if(data != null)
                        {
    img_1.setImageBitmap(photo_camera);
                                prefsEditor.putString(Global.PHOTO_1,capturedImageFilePath);
    }
    }
case IMAGE_PICK:
                if(resultCode == RESULT_OK)
                {  
                    Uri selectedImage = data.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);
                    cursor.close();

//                  Bitmap photo = BitmapFactory.decodeFile(filePath);
                   Bitmap photo_gallery = BitmapFactory.decodeFile(filePath,options);
                   img_1.setImageBitmap(photo_gallery);
                        prefsEditor.putString(Global.PHOTO_1, filePath);
}

}
        prefsEditor.commit();
}

5). in onDestroy() You have to destroy all bitmap which you setted.

@Override
    public void onDestroy()
    {
        super.onDestroy();
        if(photo_camera != null)
        {
            photo_camera.recycle();
        }
        if(photo_gallery != null)
        {
            photo_gallery.recycle();
        }
}

6). At the time when you fetch data from sharedPrefrences you have to convert string in to Bitmap and then you can set bitmap in ImageView. for example, Bitmap bit1 = BitmapFactory.decodeFile(strimg1); and then set , imageView.setImageBitmap


Don't store bitmaps in a sharedpreference. If you need to persist it during the lifetime of your application, you can assign it to a static field. If you want to persist it even across device reboots, put it in a file or on the database.

For more information, read http://developer.android.com/resources/faq/framework.html#3


You can add values in SharedPreference like this:

SharedPreferences pref = getSharedPreferences("abc", 0);
Editor edit = pref.edit();
edit.putBoolean(arg0, arg1);
edit.putFloat(arg0, arg1);
edit.putInt(arg0, arg1);
edit.putLong(arg0, arg1);
edit.putString(arg0, arg1);
edit.commit();

You can add only Boolean, Float, Int, Long, String values in SharedPreference.

To store image you should external or internal memory of device.


Let's say the bitmap image as bitmapImg, you can store the bitmap image after converting into a base64String like the below

SharedPreferences mSharedPreferences = context.getSharedPreferences("MyPreferences", Context.MODE_PRIVATE);

ByteArrayOutputStream baos = new ByteArrayOutputStream();
bitmapImg.compress(Bitmap.CompressFormat.JPEG, 100, baos);

byte[] compressImage = baos.toByteArray();
String sEncodedImage = Base64.encodeToString(compressImage, Base64.DEFAULT);

mSharedPreferences.edit().putString("keyStoredImage",sEncodedImage);
mSharedPreferences.edit().commit();

And retrieve the Stored Image from the SharedPreference like the below

if(mSharedPreferences.contains("keyStoredImage"))
{

String encodedImage = mSharedPreferences.getString("keyStoredImage",null);

byte[] b = Base64.decode(encodedImage, Base64.DEFAULT);

Bitmap bitmapImage = BitmapFactory.decodeByteArray(b, 0, b.length);
}
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