Develop Reference

Null reference when choosing a pdf file to send to server

When i choose a PDF file from my device's folders, I keep getting a null reference no matter the path I set it to, I have no idea what is causing this null reference so I need help.
I referred to this to pick the PDF file from the device, but it does not show how to send to the server.
The following is my code.
public void btnOtherFilesOnClick(View v){
int PDF = 1;
Intent i = new Intent();
i.setType("application/pdf");
i.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(i, "Select Pdf"), PDF);
btnNo = 6;
}
else if (btnNo == 6 ) {
// File downloads = new File(String.valueOf(Environment.getExternalStorageState()));
//create new file directory object
//File downloads = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).getAbsolutePath());
Uri selectedImage = data.getData();
String[] filePathColumn = {MediaStore.Files.FileColumns.DATA};
Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
cursor.close();
picturePath = cursor.getString(columnIndex);
file = new File(picturePath);
copyDatabaseToSD();
createServerPDFStorage();
my picturePath keeps being null even though my filePathColumn[0] is not. I'm trying to send the PDF to SQLite server.

Get the latest image from external storage in android

I want to load the latest image from the external storage in Android.
Do you have any ideas how to get the name of the latest image?
Currently, I load a certain picture from the gallery this way:
File externalDirectory = Environment.getExternalStorageDirectory();
File directory = new File (externalDirectory.getAbsolutePath());
File file = new File(directory, "pic.jpg");
FileInputStream streamIn = null;
try {
streamIn = new FileInputStream(file);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
So is there a way to load the latest?

String[] projection = new String[]{
MediaStore.Images.ImageColumns._ID,
MediaStore.Images.ImageColumns.DATA,
MediaStore.Images.ImageColumns.BUCKET_DISPLAY_NAME, //the album it in
MediaStore.Images.ImageColumns.DATE_TAKEN,
MediaStore.Images.ImageColumns.MIME_TYPE
};
final Cursor cursor = getContext().getContentResolver()
.query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, projection, null,
null, MediaStore.Images.ImageColumns.DATE_TAKEN + " DESC");
// Put it in the image view
if (cursor.moveToFirst()) {
final ImageView imageView = (ImageView) findViewById(R.id.pictureView);
String imageLocation = cursor.getString(1);
File imageFile = new File(imageLocation);
if (imageFile.exists()) { // TODO: is there a better way to do this?
Bitmap bm = BitmapFactory.decodeFile(imageLocation);
imageView.setImageBitmap(bm);
}
}
Use content resolver
Updated :
if you mean you want to load an image from a certain directory you create for storing image you need to make sure in every device that certain directory is created. You can use a while loop to loop through all the image by checking wether the BUCKET_DISPLAY_NAME also known as album have the same name to your created album. If yes get the first picture since you already order it by descending order sort by date time.
int albumColumn = cur.getColumnIndexOrThrow(MediaStore.Images.Media.BUCKET_DISPLAY_NAME);
do{
String album = cur.getString(albumColumn);
if(album == "YOUR CREATE DIR"){
break;
}
}while(cursor.moveToNext());
Integrate this code with the above code with your own logic. Basically the BUCKET_DISPLAY_NAME is the album which I mention earlier.

you may try this
String path = "/mnt/sdcard/Videos/Videoname"; // Your path
String fileName = new File(path).getName(); // you file name

Getting file from content uri for videos taken

I have a method below:
private String getRealPathFromUriForVideos(Uri selectedVideoUri) {
String wholeID = DocumentsContract.getDocumentId(selectedVideoUri);
String id = wholeID.split(":")[1];
String[] column = { MediaStore.Video.Media.DATA };
String sel = MediaStore.Video.Media._ID + "=?";
Cursor cursor = getContentResolver().query(MediaStore.Video.Media.EXTERNAL_CONTENT_URI, column, sel, new String[]{ id }, null);
String filePath = "";
int columnIndex = cursor.getColumnIndex(column[0]);
if (cursor.moveToFirst()) {
filePath = cursor.getString(columnIndex);
}
cursor.close();
return filePath;
}
This works just fine getting the file for videos that hte user selects. However, I want to allow users to also create new videos (from my app) and then get the URI and the file from there. The URI for newly created videos is: content://media/external/video/media/41. For selected videos is like content://com.android.providers.media.documents/document/video%3A42.
It works with the second one but not the first one. First one I get IllegalArgumentException because its not a document URI. How can I get the file from the first URI?

This works just fine getting the file for videos that hte user selects
It may work in a few situations. It will not work in general. A Uri that you get from something like ACTION_OPEN_DOCUMENT does not have to represent a file, let alone one that you can access via the filesystem, let alone one that this script-kiddie algorithm will let you access.
The URI for newly created videos is: content://media/external/video/media/41
Not necessarily. I suppose that there is a way that you get a Uri like that for a recorded video, though off the top of my head I cannot think of a recommended way that would give you such a Uri. If you are using MediaRecorder or ACTION_VIDEO_CAPTURE, you create your own file (and, for ACTION_VIDEO_CAPTURE, your own Uri for that file). And, if you are creating your own file, you know where that file is.
Need to be able to upload to my server
For the video, record to a file that you control, then use that file.
Use some library that lets you upload from a Uri or InputStream. Otherwise:
Use ContentResolver and openFileInput() to get an InputStream on the content represented by the Uri
Create a FileOutputStream on some file that you control (e.g., in getCacheDir())
Copy the content from the InputStream to the OutputStream
Use your copy for the upload
Delete your copy when the work is done
You treat a foreign Uri as if it were a URL to a Web server: stream the content.

Seems to get it from the second URI I need this:
private String getRealPathFromUriForImagesAndVideo(Uri contentUri) {
Cursor cursor = null;
try {
String[] proj = {MediaStore.Images.Media.DATA};
cursor = getContentResolver().query(contentUri, proj, null, null, null);
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
} catch (Exception e) {
return contentUri.getPath();
} finally {
if (cursor != null) {
cursor.close();
}
}
}

Android Gallery doesn't support streamed files

In my app the user can select files and open them in the appropriate app (using an ACTION_VIEW intent).
I need to do some work on the data before giving it to the other app. So I'm using a streaming solution : I implemented a ContentProvider that implements openTypedAssetFile and writeDataToPipe (this method fills the output ParcelFileDescriptor created by openPipeHelper).
This works : I can open .pdf files, .txt files etc. The streaming seems correct.
I can open images usings 3-party apps.
However when I open an image using the Gallery, it doesn't work (Gallery shows a black screen), and I get the following exception :
fail to open myfile.jpg
UriImage(21890): java.io.FileNotFoundException: Not a whole file
I had a look at the Gallery source (here) and I could see that the exception is thrown here :
try {
if (MIME_TYPE_JPEG.equalsIgnoreCase(mContentType)) {
InputStream is = mApplication.getContentResolver()
.openInputStream(mUri);
mRotation = Exif.getOrientation(is);
Utils.closeSilently(is);
}
**mFileDescriptor = mApplication.getContentResolver()
.openFileDescriptor(mUri, "r");**
if (jc.isCancelled()) return STATE_INIT;
return STATE_DOWNLOADED;
} catch (FileNotFoundException e) {
Log.w(TAG, "fail to open: " + mUri, e);
return STATE_ERROR;
}
However, once in the Gallery app, if I select "Set as wallpaper", then I can see my image, it is then well streamed. So the problem appears when Gallery opens.
After a deeper look (in the ContentResolver code etc.) I couldn't understand why it behaves this way. It seems that Gallery does not support streaming files. Is that right ?
Do you have any idea ?
Thanks a lot.

String scheme = mUri.getScheme();
ContentResolver contentResolver = getContentResolver();
// If we are sent file://something or
// content://org.openintents.filemanager/mimetype/something...
if (scheme.equals("file")
|| (scheme.equals("content") && fileUri
.getEncodedAuthority().equals(
"org.openintents.filemanager"))) {
// Get the path
filePath = fileUri.getPath();
// Trim the path if necessary
// openintents filemanager returns
// content://org.openintents.filemanager/mimetype//mnt/sdcard/xxxx.jpg
if (filePath.startsWith("/mimetype/")) {
String trimmedFilePath = filePath
.substring("/mimetype/".length());
filePath = trimmedFilePath.substring(trimmedFilePath
.indexOf("/"));
}
} else if (scheme.equals("content")) {
// If we are given another content:// URI, look it up in the
// media provider
filePath = getFilePathFromContentUri(fileUri,
contentResolver);
} else {
Log.e("filePath--------->>>>>", filePath + "");
}
and
private String getFilePathFromContentUri(Uri selectedVideoUri,
ContentResolver contentResolver) {
String filePathString;
String[] filePathColumn = { MediaColumns.DATA };
Cursor cursor = contentResolver.query(selectedVideoUri, filePathColumn,
null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
filePathString = cursor.getString(columnIndex);
cursor.close();
return filePathString;
}
and now use this filepath ..
try {
if (MIME_TYPE_JPEG.equalsIgnoreCase(mContentType)) {
InputStream is = mApplication.getContentResolver()
.openInputStream(filePath); // ** change is here
mRotation = Exif.getOrientation(is);
Utils.closeSilently(is);
}
** mFileDescriptor = mApplication.getContentResolver()
.openFileDescriptor(filePath, "r"); **
if (jc.isCancelled()) return STATE_INIT;
return STATE_DOWNLOADED;
} catch (FileNotFoundException e) {
Log.w(TAG, "fail to open: " + mUri, e);
return STATE_ERROR;
}
this is work for me

Refreshing the thumbnail using MediaScanner

When I save an image to new location and then use MediaScanner to refresh the gallery then everything is fine - thumbnails and images are refreshed well.
But when I save an image to EXISTING location and then use MediaScanner - then only 'new' thumbnail isnt refreshed. (even though file is overwritten).
How to solve it?
Here is my code :
File file = new File(SDCARD_PATH, filename);
try {
FileOutputStream out = new FileOutputStream(file);
bmp.compress(format, BEST_IMAGE_QUALITY, out);
}catch (FileNotFoundException e) {
}
//refreshing single file using media scanner, no need to paste

This is a common and well know problem in Android. If you edit a media file, the thumbnail does not seem to update.
I have a fix for this, however, its still a fix and not a clean solution.
My fix is simple, and it basically deletes the stale thumbnail and then uses media scanner to update the thumbnails.
Here're the steps to be followed:
Step 1. Edit the file as you like. Say filename, "myVideoToBeEdited".
Step 2. Once you are done editing, delete its existing thumbnail.
First, get the video id using code like this:
final String[] columns = {
BaseColumns._ID, MediaColumns.DATA
};
ContentResolver cr = context.getContentResolver();
Cursor cursor = cr.query(MediaStore.Video.Media.EXTERNAL_CONTENT_URI, columns, null, null, null);
boolean cancel = false;
if(null != cursor){
while(cursor.moveToNext() && !cancel){
String fileName = cursor.getString(cursor.getColumnIndex(MediaColumns.DATA));
int imageId = cursor.getInt(cursor.getColumnIndex(BaseColumns._ID));
if(fileName.equals(myVideoToBeEdited)){
removeVideoThumbnail(getContentResolver(), imageId); // step 3
cancel = true;
}
}
}
There are other ways to get the id, and more optimised ones as well.
Step 3. Delete the thumbnail.
public void removeVideoThumbnail(ContentResolver contentResolver, long photoId) {
Cursor thumbnails = contentResolver.query(android.provider.MediaStore.Video.Thumbnails.EXTERNAL_CONTENT_URI, null, android.provider.MediaStore.Video.Thumbnails.VIDEO_ID + "=?", new String[]{String.valueOf(photoId)}, null);
for (thumbnails.moveToFirst(); !thumbnails.isAfterLast(); thumbnails.moveToNext()) {
long thumbnailId = thumbnails.getLong(thumbnails.getColumnIndex(android.provider.MediaStore.Video.Thumbnails._ID));
String path = thumbnails.getString(thumbnails.getColumnIndex(android.provider.MediaStore.Video.Thumbnails.DATA));
File file = new File(path);
if (file.delete()) {
contentResolver.delete(android.provider.MediaStore.Video.Thumbnails.EXTERNAL_CONTENT_URI, android.provider.MediaStore.Video.Thumbnails._ID + "=?", new String[]{String.valueOf(thumbnailId)});
}
}
}
Or, here's the method to delete image thumbnail
public void removeImageThumbnail(ContentResolver contentResolver, long photoId) {
Cursor thumbnails = contentResolver.query(android.provider.MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI, null, android.provider.MediaStore.Images.Thumbnails.IMAGE_ID + "=?", new String[]{String.valueOf(photoId)}, null);
for (thumbnails.moveToFirst(); !thumbnails.isAfterLast(); thumbnails.moveToNext()) {
long thumbnailId = thumbnails.getLong(thumbnails.getColumnIndex(android.provider.MediaStore.Images.Thumbnails._ID));
String path = thumbnails.getString(thumbnails.getColumnIndex(android.provider.MediaStore.Images.Thumbnails.DATA));
File file = new File(path);
if (file.delete()) {
contentResolver.delete(android.provider.MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI, android.provider.MediaStore.Images.Thumbnails._ID + "=?", new String[]{String.valueOf(thumbnailId)});
}
}
}
Step 4. And finally use media scanner connection to scan the file so that it updates the thumbnails.
MediaScannerConnection.scanFile(context,
new String[] { myVideoToBeEdited }, null,
new MediaScannerConnection.OnScanCompletedListener() {
public void onScanCompleted(String path, Uri uri) {
// pass the mime type, else passing a null will enable file extension to dictate the mime type
// you are good to go
}
});

Have you tried to remove the "old" picture prior to saving the new one to file system? Like so:
File file = new File(SDCARD_PATH, filename);
try {
// Delete the "old" file.
if (file.exists()) {
file.delete();
}
FileOutputStream out = new FileOutputStream(file);
bmp.compress(format, BEST_IMAGE_QUALITY, out);
}catch (FileNotFoundException e) {
}catch (SecurityException e) {
}