Develop Reference

how to save multiple bitmaps fastly in android studio

I want to save bitmaps in the gallery.
Currently, I am using the following code:
public void saveBitmap(Bitmap output){
String filepath = Environment.getExternalStorageDirectory().toString() + "/Imverter/ImverterEffectedImage";
File dir = new File(filepath);
if(!dir.exists()){
dir.mkdir();
}
String fileName = "Imverter" + System.currentTimeMillis() + ".jpg";
File image = new File(dir, fileName);
try {
FileOutputStream fileOutputStream = new FileOutputStream(image);
output.compress(Bitmap.CompressFormat.JPEG, 80, fileOutputStream);
fileOutputStream.flush();
fileOutputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
It saves one single bitmap efficiently, but in my app, I have to deal with multiple bitmaps, and this method results in the slow output.
I want to store every single bitmap in a different files.
Thanks in advance.

Get path of a drawable image so that I can post it to the backend

I have a set of icons stored in the drawable folder.
Based on users selection I'll be posting these icons to the backend.
When I try to retrieve the path for these drawables, I get the following error
HTTP FAILED: java.io.FileNotFoundException: (No such file or directory)
This is how I am getting the path
public String getURLForResource (int resourceId) {
return Uri.parse("android.resource://"+ BuildConfig.APPLICATION_ID+"/" +resourceId).toString();
}
File fileToUpload = new File(getURLForResource(R.drawable.icon));
I have referred the following link says that it's not possible to retrieve the path for a drawable.
Any idea on how I can solve this problem?

As solution you can write your drawable to file.
Convert drawable to bitmap
Bitmap bm = BitmapFactory.decodeResource(mContext.getResources(), R.drawable.your_drawable);
Save bitmap to file
String path = Environment.getExternalStorageDirectory().toString();
File file = new File(path, "image" + System.currentTimeMillis() + ".jpg");
try (FileOutputStream out = new FileOutputStream(file)) {
bm.compress(Bitmap.CompressFormat.PNG, 100, out);
out.flush(); // Not really required
out.close(); // do not forget to close the stream
} catch (IOException e) {
e.printStackTrace();
}
You can use file now.

How to create a raw image file with content inside to emulate an SD card for Android

I'm working on app which will read folders and files from an SD card, now to need to create a raw image file which will emulate the SD card, but when I use mksdcard it only creates an empty raew image file.

void saveImage() {
File filename;
try {
String path = Environment.getExternalStorageDirectory().toString();
new File(path + "/folder/subfolder").mkdirs();
filename = new File(path + "/folder/subfolder/image.jpg");
FileOutputStream out = new FileOutputStream(filename);
bitMapImg.compress(Bitmap.CompressFormat.JPEG, 90, out);
out.flush();
out.close();
MediaStore.Images.Media.insertImage(getContentResolver(), filename.getAbsolutePath(), filename.getName(), filename.getName());
Toast.makeText(getApplicationContext(), "File is Saved in " + filename, 1000).show();
} catch (Exception e) {
e.printStackTrace();
}
}

Android, How to store image in internal storage?

I want to store bitmap image on internal storage (not external storage). I have written this code but it seems something has problem. Because when i download image from DDMS, I can't open it.
public String writeFileToInternalStorage(Context context, Bitmap outputImage) {
String fileName = Long.toString(System.currentTimeMillis()) + ".png";
try {
OutputStreamWriter osw = new OutputStreamWriter(context.openFileOutput(fileName, Context.MODE_PRIVATE));
osw.write(outputImage.toString());
Log.i(TAG, "Image stored at: " + fileName);
} catch (Exception e) {
Log.w(TAG, e.toString());
fileName = null;
}
return fileName;
}

outputImage.toString() is not the image :) the contant you put on the file is not the binary data, but some string!
A way to do it is this:
public String writeFileToInternalStorage(Context context, Bitmap outputImage) {
String fileName = Long.toString(System.currentTimeMillis()) + ".png";
final FileOutputStream fos = openFileOutput(fileName, Context.MODE_PRIVATE);
outputImage.compress(CompressFormat.PNG, 90, fos);
}
I coded directly into the browser, it is possible to have some syntax errors, but the code should work.

The problem is that you use .toString() instead of compressing the Bitmap into a FileOutputStream:
FileOutputStream out = new FileOutputStream(filename);
outputImage.compress(Bitmap.CompressFormat.PNG, 90, out);
The internal storage can be retrieved via the Context, too.
File cacheDir = context.getCacheDir();

Store Bitmap image to SD Card in Android

I am facing some strange problem with my android code,
I have an image in Bitmap variable and want to save that file to SD card.
I code as follow,
Bitmap IMAGE // Loaded from internet servers.;
try {
File _sdCard = Environment.getExternalStorageDirectory();
File _picDir = new File(_sdCard, "MyDirectory");
_picDir.mkdirs();
File _picFile = new File(_picDir, "MyImage.jpg");
FileOutputStream _fos = new FileOutputStream(_picFile);
IMAGE.compress(Bitmap.CompressFormat.JPEG, 100, _fos);
_fos.flush();
_fos.close();
Toast.makeText(this, "Image Downloaded", 7000).show();
} catch (Exception ex) {
ex.printStackTrace();
Toast.makeText(this, ex.getMessage(), 7000).show();
}
I am using Sony Experia Arc as my testing device, when the phone is connected to my computer, the code works nice, it stores image and also displays in gallery. But when I disconnect phone from my computer and test the app, it doesn't save picture and doesn't show any exception.

use this function
void saveImage() {
String root = Environment.getExternalStorageDirectory().toString();
File myDir = new File(root + "/saved_images");
String fname = "Image.jpg";
File file = new File (myDir, fname);
if (file.exists ()) file.delete ();
try {
FileOutputStream out = new FileOutputStream(file);
myBitmap.compress(Bitmap.CompressFormat.JPEG, 90, out);
out.flush();
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}
Check this answer will give more details Android saving file to external storage

ByteArrayOutputStream bytes = new ByteArrayOutputStream();
thumbnail.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
//4
File file = new File(Environment.getExternalStorageDirectory()+File.separator + "image.jpg");
try {
file.createNewFile();
FileOutputStream fo = new FileOutputStream(file);
//5
fo.write(bytes.toByteArray());
fo.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

**This Code Cover the Following Topics**
1. Save a bitmap Image on sdcard a jpeg
2. Create a folder on sdcard
3. Create every file Separate name
4. Every file save with date and time
5. Resize the image in very small size
6. Best thing image Quality fine not effected from Resizing
The following method is used to create an image file using the bitmap
public void createImageFromBitmap(Bitmap bmp) {
FileOutputStream fileOutputStream = null;
try {
// create a File object for the parent directory
File wallpaperDirectory = new File("/sdcard/Capture/");
// have the object build the directory structure, if needed.
wallpaperDirectory.mkdirs();
//Capture is folder name and file name with date and time
fileOutputStream = new FileOutputStream(String.format(
"/sdcard/Capture/%d.jpg",
System.currentTimeMillis()));
// Here we Resize the Image ...
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.JPEG, 100,
byteArrayOutputStream); // bm is the bitmap object
byte[] bsResized = byteArrayOutputStream.toByteArray();
fileOutputStream.write(bsResized);
fileOutputStream.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
}
}
and add this in manifest
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />