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java - How to save an image in Android Q using MediaStore?

Here is a link to the new Android Q Scoped Storage.

According to this Android Developers Best Practices Blog, storing shared media files (which is my case) should be done using the MediaStore API.

Digging into the docs and I cannot find a relevant function.

Here is my trial in Kotlin:

val bitmap = getImageBitmap() // I have a bitmap from a function or callback or whatever
val name = "example.png" // I have a name

val picturesDirectory = getExternalFilesDir(Environment.DIRECTORY_PICTURES)!!

// Make sure the directory "Android/data/com.mypackage.etc/files/Pictures" exists
if (!picturesDirectory.exists()) {
    picturesDirectory.mkdirs()
}

try {
    val out = FileOutputStream(File(picturesDirectory, name))
    bitmap.compress(Bitmap.CompressFormat.PNG, 100, out)

    out.flush()
    out.close()

} catch(e: Exception) {
    // handle the error
}

The result is that my image is saved here Android/data/com.mypackage.etc/files/Pictures/example.png as described in the Best Practices Blog as Storing app-internal files


My question is:

How to save an image using the MediaStore API?


Answers in Java are equally acceptable.

Thanks in Advance!


EDIT

Thanks to PerracoLabs

That really helped!

But there are 3 more points.

Here is my code:

val name = "Myimage"
val relativeLocation = Environment.DIRECTORY_PICTURES + File.pathSeparator + "AppName"

val contentValues  = ContentValues().apply {
    put(MediaStore.Images.ImageColumns.DISPLAY_NAME, name)
    put(MediaStore.MediaColumns.MIME_TYPE, "image/png")

    // without this part causes "Failed to create new MediaStore record" exception to be invoked (uri is null below)
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
        put(MediaStore.Images.ImageColumns.RELATIVE_PATH, relativeLocation)
    }
}

val contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI
var stream: OutputStream? = null
var uri: Uri? = null

try {
    uri = contentResolver.insert(contentUri, contentValues)
    if (uri == null)
    {
        throw IOException("Failed to create new MediaStore record.")
    }

    stream = contentResolver.openOutputStream(uri)

    if (stream == null)
    {
        throw IOException("Failed to get output stream.")
    }

    if (!bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream))
    {
        throw IOException("Failed to save bitmap.")
    }


    Snackbar.make(mCoordinator, R.string.image_saved_success, Snackbar.LENGTH_INDEFINITE).setAction("Open") {
        val intent = Intent()
        intent.type = "image/*"
        intent.action = Intent.ACTION_VIEW
        intent.data = contentUri
        startActivity(Intent.createChooser(intent, "Select Gallery App"))
    }.show()

} catch(e: IOException) {
    if (uri != null)
    {
        contentResolver.delete(uri, null, null)
    }

    throw IOException(e)

}
finally {
    stream?.close()
}

1- The image saved doesn't get its correct name "Myimage.png"

I tried using "Myimage" and "Myimage.PNG" but neither worked.

The image always gets a name made up of numbers like:

1563468625314.jpg

Which bring us to the second problem:

2- The image is saved as jpg even though I compress the bitmap in the format of png.

Not a big issue. Just curious why.

3- The relativeLocation bit causes an exception on Devices less than Android Q. After surrounding with the "Android Version Check" if statement, the images are saved directly in the root of the Pictures folder.

Another Thank you.


EDIT 2

Changed to:

uri = contentResolver.insert(contentUri, contentValues)
if (uri == null)
{
    throw IOException("Failed to create new MediaStore record.")
}

val cursor = contentResolver.query(uri, null, null, null, null)
DatabaseUtils.dumpCursor(cursor)
cursor!!.close()

stream = contentResolver.openOutputStream(uri)

Here are the logs

I/System.out: >>>>> Dumping cursor android.content.ContentResolver$CursorWrapperInner@76da9d1
I/System.out: 0 {
I/System.out:    _id=25417
I/System.out:    _data=/storage/emulated/0/Pictures/1563640732667.jpg
I/System.out:    _size=null
I/System.out:    _display_name=Myimage
I/System.out:    mime_type=image/png
I/System.out:    title=1563640732667
I/System.out:    date_added=1563640732
I/System.out:    is_hdr=null
I/System.out:    date_modified=null
I/System.out:    description=null
I/System.out:    picasa_id=null
I/System.out:    isprivate=null
I/System.out:    latitude=null
I/System.out:    longitude=null
I/System.out:    datetaken=null
I/System.out:    orientation=null
I/System.out:    mini_thumb_magic=null
I/System.out:    bucket_id=-1617409521
I/System.out:    bucket_display_name=Pictures
I/System.out:    width=null
I/System.out:    height=null
I/System.out:    is_hw_privacy=null
I/System.out:    hw_voice_offset=null
I/System.out:    is_hw_favorite=null
I/System.out:    hw_image_refocus=null
I/System.out:    album_sort_index=null
I/System.out:    bucket_display_name_alias=null
I/System.out:    is_hw_burst=0
I/System.out:    hw_rectify_offset=null
I/System.out:    special_file_type=0
I/System.out:    special_file_offset=null
I/System.out:    cam_perception=null
I/System.out:    cam_exif_flag=null
I/System.out: }
I/System.out: <<<<<

I noticed the title to be matching the name so I tried adding:

put(MediaStore.Images.ImageColumns.TITLE, name)

It still didn't work and here are the new logs:

I/System.out: >>>>> Dumping cursor android.content.ContentResolver$CursorWrapperInner@51021a5
I/System.out: 0 {
I/System.out:    _id=25418
I/System.out:    _data=/storage/emulated/0/Pictures/1563640934803.jpg
I/System.out:    _size=null
I/System.out:    _display_name=Myimage
I/System.out:    mime_type=image/png
I/System.out:    title=Myimage
I/System.out:    date_added=1563640934
I/System.out:    is_hdr=null
I/System.out:    date_modified=null
I/System.out:    description=null
I/System.out:    picasa_id=null
I/System.out:    isprivate=null
I/System.out:    latitude=null
I/System.out:    longitude=null
I/System.out:    datetaken=null
I/System.out:    orientation=null
I/System.out:    mini_thumb_magic=null
I/System.out:    bucket_id=-1617409521
I/System.out:    bucket_display_name=Pictures
I/System.out:    width=null
I/System.out:    height=null
I/System.out:    is_hw_privacy=null
I/System.out:    hw_voice_offset=null
I/System.out:    is_hw_favorite=null
I/System.out:    hw_image_refocus=null
I/System.out:    album_sort_index=null
I/System.out:    bucket_display_name_alias=null
I/System.out:    is_hw_burst=0
I/System.out:    hw_rectify_offset=null
I/System.out:    special_file_type=0
I/System.out:    special_file_offset=null
I/System.out:    cam_perception=null
I/System.out:    cam_exif_flag=null
I/System.out: }
I/System.out: <<<<<

And I can't change date_added to a name.

And MediaStore.MediaColumns.DATA is deprecated.

Thanks in Advance!

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1 Answer

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by (71.8m points)

Try the next method. Android Q (and above) already takes care of creating the folders if they don’t exist. The example is hard-coded to output into the DCIM folder. If you need a sub-folder then append the sub-folder name as next:

final String relativeLocation = Environment.DIRECTORY_DCIM + File.separator + “YourSubforderName”;

Consider that the compress format should be related to the mime-type parameter. For example, with a JPEG compress format the mime-type would be "image/jpeg", and so on. Probably you may also want to pass the compress quality as a parameter, in this example is hardcoded to 95.

Java:

@NonNull
public Uri saveBitmap(@NonNull final Context context, @NonNull final Bitmap bitmap,
                      @NonNull final Bitmap.CompressFormat format,
                      @NonNull final String mimeType,
                      @NonNull final String displayName) throws IOException {

    final ContentValues values = new ContentValues();
    values.put(MediaStore.MediaColumns.DISPLAY_NAME, displayName);
    values.put(MediaStore.MediaColumns.MIME_TYPE, mimeType);
    values.put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM);

    final ContentResolver resolver = context.getContentResolver();
    Uri uri = null;

    try {
        final Uri contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
        uri = resolver.insert(contentUri, values);

        if (uri == null)
            throw new IOException("Failed to create new MediaStore record.");

        try (final OutputStream stream = resolver.openOutputStream(uri)) {
            if (stream == null)
                throw new IOException("Failed to open output stream.");
         
            if (!bitmap.compress(format, 95, stream))
                throw new IOException("Failed to save bitmap.");
        }

        return uri;
    }
    catch (IOException e) {

        if (uri != null) {
            // Don't leave an orphan entry in the MediaStore
            resolver.delete(uri, null, null);
        }

        throw e;
    }
}

Kotlin:

@Throws(IOException::class)
fun saveBitmap(
    context: Context, bitmap: Bitmap, format: Bitmap.CompressFormat,
    mimeType: String, displayName: String
): Uri {

    val values = ContentValues().apply {
        put(MediaStore.MediaColumns.DISPLAY_NAME, displayName)
        put(MediaStore.MediaColumns.MIME_TYPE, mimeType)
        put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM)
    }

    val resolver = context.contentResolver
    var uri: Uri? = null

    try {
        uri = resolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)
            ?: throw IOException("Failed to create new MediaStore record.")

        resolver.openOutputStream(uri)?.use {
            if (!bitmap.compress(format, 95, it))
                throw IOException("Failed to save bitmap.")
        } ?: throw IOException("Failed to open output stream.")

        return uri

    } catch (e: IOException) {

        uri?.let { orphanUri ->
            // Don't leave an orphan entry in the MediaStore
            resolver.delete(orphanUri, null, null)
        }

        throw e
    }
}

Kotlin variant, with a more functional style:

@Throws(IOException::class)
fun saveBitmap(
    context: Context, bitmap: Bitmap, format: Bitmap.CompressFormat,
    mimeType: String, displayName: String
): Uri {

    val values = ContentValues().apply {
        put(MediaStore.MediaColumns.DISPLAY_NAME, displayName)
        put(MediaStore.MediaColumns.MIME_TYPE, mimeType)
        put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM)
    }

    var uri: Uri? = null

    return runCatching {
        with(context.contentResolver) {
            insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)?.also {
                uri = it // Keep uri reference so it can be removed on failure

                openOutputStream(it)?.use { stream ->
                    if (!bitmap.compress(format, 95, stream))
                        throw IOException("Failed to save bitmap.")
                } ?: throw IOException("Failed to open output stream.")

            } ?: throw IOException("Failed to create new MediaStore record.")
        }
    }.getOrElse {
        uri?.let { orphanUri ->
            // Don't leave an orphan entry in the MediaStore
            context.contentResolver.delete(orphanUri, null, null)
        }

        throw it
    }
}

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