I'm trying to build a feature to load the latest saved image from the device into an app.
Currently I'm using this path DCIM/Camera/ but it only stores camera taken images. Is there a folder that stores all images? (screenshots, images saved from the web or camera roll)
Instead of searching in in folders for the images, you can let the system take care of that for you.
Android indexes most media-data (images, music, etc) on it's own and offers Content Providers to query these databases.
For your purposes, you can use the MediaStore.Images.Media-provider.
public List<String> getImagePaths(Context context) {
// The list of columns we're interested in:
String[] columns = {MediaStore.Images.Media.DATA, MediaStore.Images.Media.DATE_ADDED};
final Cursor cursor = context.getContentResolver().
query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, // Specify the provider
columns, // The columns we're interested in
null, // A WHERE-filter query
null, // The arguments for the filter-query
MediaStore.Images.Media.DATE_ADDED + " DESC" // Order the results, newest first
);
List<String> result = new ArrayList<String>(cursor.getCount());
if (cursor.moveToFirst()) {
final int image_path_col = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
do {
result.add(cursor.getString(image_path_col));
} while (cursor.moveToNext());
}
cursor.close();
return result;
}
The method will return a list of the image-paths of all images that are currently indexed by the MediaStore with the latest first. You'll need the android.permission.READ_EXTERNAL_STORAGE-permission for this to work!
Related
I want to store an image (size approx. 10MB) in the SQLite database. For that I created a DB helper, a Dao. Everything works fine, I can create several records and read them without a problem, I can even update the blob in the latest record without a problem.
But if I go back to an older record and update the blob, I cannot load this record with the blob any longer.
I have a list view where I show all the records, and for that I use a select that doesn't return the blob. This list works fine, but when I click on an item in the list, I try to load the record with the blob, the cursor returns 0 rows.
public void save(Bill aBill) {
ContentValues values = new ContentValues();
values.put(DatabaseHelper.BILL_NAME_COLUMN, aBill.getName());
values.put(DatabaseHelper.BILL_DUE_DATE_COLUMN, getContentValue(aBill.getDueDate()));
values.put(DatabaseHelper.BILL_IMAGE_COLUMN, aBill.getImage());
if (!aBill.isPersistent()) {
aBill.setId(database.insert(DatabaseHelper.BILL_TABLE, null, values));
aBill.setPersistent(true);
} else {
database.update(DatabaseHelper.BILL_TABLE, values, DatabaseHelper.BILL_ID_COLUMN + "=?", new String[]{String.valueOf(aBill.getId())});
}
}
// fails after updating the blob
public Bill get(long id) {
Cursor cursor = database.query(DatabaseHelper.BILL_TABLE,
new String[]{DatabaseHelper.BILL_ID_COLUMN, DatabaseHelper.BILL_NAME_COLUMN, DatabaseHelper.BILL_DUE_DATE_COLUMN, DatabaseHelper.BILL_IMAGE_COLUMN}, "id = ?", new String[] {String.valueOf(id)}, null,
null, DatabaseHelper.BILL_DUE_DATE_COLUMN);
Bill bill = null;
while (cursor.moveToNext()) {
bill = new Bill();
bill.setPersistent(true);
bill.setId(cursor.getLong(cursor.getColumnIndex(DatabaseHelper.BILL_ID_COLUMN)));
bill.setName(cursor.getString(cursor.getColumnIndex(DatabaseHelper.BILL_NAME_COLUMN)));
bill.setDueDate(getDate(cursor.getString(cursor.getColumnIndex(DatabaseHelper.BILL_DUE_DATE_COLUMN))));
bill.setImage(cursor.getBlob(cursor.getColumnIndex(DatabaseHelper.BILL_IMAGE_COLUMN)));
}
cursor.close();
return bill;
}
//works fine after updating the blob
public List findAll() {
List bills = new ArrayList();
Cursor cursor = database.query(DatabaseHelper.BILL_TABLE,
new String[]{DatabaseHelper.BILL_ID_COLUMN, DatabaseHelper.BILL_NAME_COLUMN, DatabaseHelper.BILL_DUE_DATE_COLUMN}, null, null, null,
null, DatabaseHelper.BILL_DUE_DATE_COLUMN);
while (cursor.moveToNext()) {
Bill bill = new Bill();
bill.setPersistent(true);
bill.setId(cursor.getLong(cursor.getColumnIndex(DatabaseHelper.BILL_ID_COLUMN)));
bill.setName(cursor.getString(cursor.getColumnIndex(DatabaseHelper.BILL_NAME_COLUMN)));
bill.setDueDate(getDate(cursor.getString(cursor.getColumnIndex(DatabaseHelper.BILL_DUE_DATE_COLUMN))));
bills.add(bill);
}
cursor.close();
return bills;
}
Here is the exception:
java.lang.IllegalStateException: Couldn't read row 0, col 0 from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it.
at android.database.CursorWindow.nativeGetLong(Native Method)
at android.database.CursorWindow.getLong(CursorWindow.java:511)
at android.database.AbstractWindowedCursor.getLong(AbstractWindowedCursor.java:75)
at net.rka.android.billreminder.BillDao.get(BillDao.java:106)
I suspect that updating a blob in a row corrupts the database somehow.
Did anybody run into a similar problem? If so how did you solve it?
Your issue is very likely due to the size of the image(s) and a quirk, for want of a better term, that you can store large BLOB's without issue, but due to the size limitations of an Android's Cursor Window of 2m, that you may not be able to retrieve the BLOB. This sometimes compounded by some of the SQLiteDatabase/Cursor (The Cursor getBlob() or it's underlying methods in this case) methods that basically hide underlying failures, in order to provide what is often a simpler development experience.
If you used the SQLiteDatabase DatabaseUtils.dumpCursor this may highlight the issue(s) that may have been hidden by the SQLiteDatabase query convenience method. So adding :-
DatabaseUtils.dumpCursor(cursor); //<<<< ADDED
while (cursor.moveToNext()) { ........
May provide clues.
I can think of 3 options :-
Rather than store the files as BLOBS, store files as files on disk and store the path in the Database.
Significantly reduce the size of the images.
Look into using C++ and the native SQLIte3 libraries to retrieve the BLOBS into a suitably sized container.
Perhaps the may be some libraries that do this. However, I don't recall any being mentioned.
Using this method of audio file retrieval from Android's external storage
Cursor cursor = getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, null, null, null);
can I actually find a resonable way to fetch a genre of the given song? MediaStore class seems to provide everything else - from song's title to its composer info - except for the genre field. Should I use MediaMetadataRetriever then? If so, how drastically can creating a MediaMetadataRetriever instance for every song on a device reduce app's performance?
Maybe there are some better ways to retrieve all audio files from both external and internal storages in android?
As mentioned at Developer's Site,
You can fetch the Genres of the Audio file using MediaStore.Audio.Genres
Sample Code :
private static String[] genresProj = {
MediaStore.Audio.Genres.NAME,
MediaStore.Audio.Genres._ID
};
int idIndex = cursor
.getColumnIndexOrThrow(MediaStore.Audio.Media._ID);
while (cursor.moveToNext()){
int id = Integer.parseInt(mediaCursor.getString(idIndex));
Uri uri = MediaStore.Audio.Genres.getContentUriForAudioId("external", id );
genresCursor = context.getContentResolver().query(uri,
genresProj , null, null, null);
int genreIndex = genresCursor.getColumnIndexOrThrow(MediaStore.Audio.Genres.NAME);
while (genresCursor.moveToNext()) {
Log.d(TAG, "Genre = " +genresCursor.getString(genreIndex));
}
}
}
To fetch other details of the Audio file, please check here .
I would like to detect the camera folder on every Android device. From what I've read this folder differs from an manufacturer to another and there is no guarantee that there will be even an DCIM folder on the device.
This is the method that I'm using to get the files now:
private static final Set<String> FILTER_FOLDERS = new HashSet<String>(
Arrays.asList(new String[] { "camera", "100andro", "100media" }));
private Set<String> getCameraPictures() {
final String[] columns = new String[] {
MediaStore.Images.ImageColumns._ID,
MediaStore.Images.ImageColumns.DATA,
MediaStore.Images.ImageColumns.BUCKET_DISPLAY_NAME,
MediaStore.Images.ImageColumns.DISPLAY_NAME,
MediaStore.Images.ImageColumns.DATE_TAKEN,
MediaStore.Images.ImageColumns.MIME_TYPE };
// Order by options - by date & descending
final String orderBy = MediaStore.Images.ImageColumns.DATE_TAKEN
+ " DESC";
// Stores all the images from the gallery in Cursor
final Cursor cursor = getContentResolver().query(
MediaStore.Images.Media.EXTERNAL_CONTENT_URI, // base URI for
// the Images
columns, // Which columns to return
null, // Which rows to return (all rows)
null, // Selection arguments (none)
orderBy); // Ordering
// Total number of images
int count = cursor.getCount();
// Create an array to store path to all the images
String[] picturesPath = new String[count];
if (cursor.moveToFirst()) {
int dataColumn = cursor
.getColumnIndex(MediaStore.Images.Media.DATA);
int bucketColumn = cursor
.getColumnIndex(MediaStore.Images.Media.BUCKET_DISPLAY_NAME);
do {
if (FILTER_FOLDERS.contains(cursor.getString(bucketColumn)
.toLowerCase(Locale.getDefault()))) {
// Store the path of the image
picturesPath[cursor.getPosition()] = cursor
.getString(dataColumn);
}
} while (cursor.moveToNext());
}
// Close the cursor
if (null != cursor) {
cursor.close();
}
return new HashSet<String>(Arrays.asList(picturesPath));
}
But this is returning images from other places also ...
How can I retrieve only the images taken with the camera ?
If there is no native way to do this, where can I find what are the names for the folders used by each manufacturer (as many as there are) so that I can filter it by BUCKET_DISPLAY_NAME ?
Thank you
LE:
I have updated the method to get the images on device & also filter the folders.
There are dozens, perhaps hundreds, of camera apps that ship with devices, to go along with thousands of camera apps available for download. None have to use a particular "camera folder" and none have to have their images indexed by MediaStore.
The conventional "camera folder" for a device will be in the location specified by Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM). That directory might not exist yet, if no camera app has used it. But, again, there is no requirement that a camera app use it -- they can store their images wherever they want to, including places that you cannot access (e.g., internal storage, "the cloud").
How can I retrieve only the images taken with the camera ?
You can't. There are well over one billion smartphones on the planet, and any phone could have pictures on it taken by any camera from any other phone, courtesy of photo-sharing apps and sites. This is on top of pictures taken by cameras other than smartphones. There is no requirement that images taken by the device's own camera need to be somehow designated as such for your benefit.
I have videoplayer app with filebrowser listing all videos on SD card
Code inspired by i want get audio files in sd card
Using ContentResolver, works as expected, but it does not update if the files on card change. I do not mean automatically, but after view/app restart. Not even reinstalling the application helped, still shows the same files. The deleted video file is not visible via PC nor it is possible to play it (This video cannot be played (translation)).
I dumped the data and the problem is not in view caching or elsewhere. I do not implement any caching of my own and failed to find anything on the matter. Thank you
Code:
// acquisition
String[] projection = {
MediaStore.Video.Media._ID,
MediaStore.Video.Media.DISPLAY_NAME,
MediaStore.Video.Media.DURATION,
MediaStore.Video.Media.DATA
};
ContentResolver resolver = getActivity().getContentResolver();
Cursor videoCursor = resolver.query(
MediaStore.Video.Media.EXTERNAL_CONTENT_URI,
projection,
null,
null,
null
);
// extraction
while(cursor.moveToNext()) {
cursorIndex = cursor.getColumnIndexOrThrow(MediaStore.Video.Media.DATA);
filepath = cursor.getString(cursorIndex);
cursorIndex = cursor.getColumnIndexOrThrow(MediaStore.Video.Media.DISPLAY_NAME);
filename = cursor.getString(cursorIndex);
cursorIndex = cursor.getColumnIndexOrThrow(MediaStore.Video.Media.DURATION);
duration = cursor.getString(cursorIndex);
result[ index++ ] = new VideoFileMetadata(filename, duration, filepath);
}
Edit 1 [14-03-2013]:
I tried adding number + " = " + number to ORDER or WHERE clause to act as a potential query caching buster, but it had no effect (although it's possible it was removed by an optimizer as a useless clause). This time I had reinstalled the application from a different machine using different certificate, but the query result remained the same, listing currently non-existing files.
You should first call cursor.moveToFirst() .
So, your cursor iteration loop should look like
if (cursor.moveToFirst()) {
do {
// cursorIndex = cursor.getColumnIndexOrThrow, etc...
} while (cursor.moveToNext());
}
This question should be a starting point to all of us who want to manipulate contacts in Android.
First things first
As I am aware, since API level 5 the Contacts API has changed, so in order to make the application work correct I need to check what android os is on the phone and if prior 5 use one content provider or else use the newer one. The only annoyance in this case is the warnings of deprecated I get. The application is build against Android 2.3.3 but needs to work from 1.5+
1. Querying contacts
This is the easiest part to do. Usually querying means getting data like Contact name, phones, picture, email and displaying it on a listview. For instance here is how I've done it in API prior 5
String[] projectionPeople = new String[] {People._ID, People.NAME,};
String[] projectionPhone = new String[] {Phones.NUMBER};
try {
// Get the base URI for People table in Contacts content provider.
// which is: content://contacts/people/
Uri contactUri = People.CONTENT_URI;
ContentResolver resolver = getContentResolver();
Cursor phonesCursor = null;
Cursor peopleCursor = resolver.query (contactUri,
projectionPeople, //Which columns to return.
"People.NAME is not null", // WHERE clause--we won't specify.
null, // Selection Args??
People.DEFAULT_SORT_ORDER); // Order-by name
if (peopleCursor != null && peopleCursor.getCount() >0)
{
// go to the beginning of the list
peopleCursor.moveToFirst();
do
{
//do something with current contact info
phoneUri= Uri.withAppendedPath(personUri, Contacts.People.Phones.CONTENT_DIRECTORY);
phonesCursor = resolver.query(phoneUri,
projectionPhone,
null,
null,
Phones.DEFAULT_SORT_ORDER);
if (phonesCursor!=null && phonesCursor.getCount()>0)
{
phonesCursor.moveToFirst();
lstPhones = new ArrayList<String>();
do
{
//add phone numbers to a List<String> for instance
} while (phonesCursor.moveToNext());
if (phonesCursor != null && !phonesCursor.isClosed())
phonesCursor.close();
} while (peopleCursor.moveToNext());
if (peopleCursor != null && !peopleCursor.isClosed())
peopleCursor.close();
}
}
catch (Exception ex)
{
}
}
Haven't tried it yet on the new api but the cursor should be like
final String[] projection = new String[] {
RawContacts.CONTACT_ID, // the contact id column
RawContacts.DELETED // column if this contact is deleted
};
final Cursor rawContacts = managedQuery(RawContacts.CONTENT_URI, // the URI for raw contact provider
projection
null, // selection = null, retrieve all entries
null, // selection is without parameters
null); // do not order
Sure, this needs to be elaborated a bit more, but it should provide the basics of simple query against Contacts content provider
2. Backup
My first thought on this was: if I know the Id of a Contact, I create tables in a sqlite database exactly how the cursor columns are and insert all the data into my tables. This is not an easy task as it requires a lot of codding not to mention that different apis have different table structures. What would be the best solution to backup one contact or multiple contacts ?
3. Delete
This should work on all apis using content providers, but data is spread on many packages and uris and I'm not sure from where to delete
4. Insert
After a contact is backed up, I may need to restore/insert it again. As in case of deletion, on which uris do I need to insert ?
Please, let's try to elaborate this issues so in the futures, who needs to use Contacts in Android apps could take this question as a solid starting point. Thank you stackoverflow community.
Here is a good starting point
http://developer.android.com/resources/samples/BusinessCard/index.html