I have a WP7 application which downloads some files from a server. Now I am saving these files to isolated storage. Is there any option to save these files in a location other than Isolated Storage. No problem for accessing these files from outside the application.The reason is that I need to open these files and show them to the user.
Is there any option to store outside Isolated Storage? If yes, how?
These are the ways you have to persist information in Windows Phone:
Save to a file in Isolated Storage (with the IsolatedStorageFile)
Save in the Application Settings (with the IsolatedStorageSettings)
Save to a database (that will be in turn saved in Isolated Storage)
Send the info to some Internet webservice/remote storage
If it is a picture file, you can save it to the Pictures Library (with the MediaLibrary - sample)
There is no other access to storage in Windows Phone right now!
Related
Photos Framework provides an API to move to folders. But, is there a way to change the status of an image to hidden, and thereby move it to the iOS Hidden folder and hiding it from the main photo gallery?
If you want to save some data privately so no other app could access it you probably need to save it into the app data container. This could be a /Documents folder for example. Take a look at FileManager class to work with file system.
Use this directory to store user-generated content. The contents of this directory can be made available to the user through file sharing; therefore, his directory should only contain files that you may wish to expose to the user.
The contents of this directory are backed up by iTunes and iCloud.
File system documentation
Currently i was saving my application data (Media) to the CacheDirectory i.e
/var/mobile/Applications/BEAFC76C-C450-4A3A-9765-A0385A9580F3/Library/Caches
and things were going fine. But recently i got a bug report that the application data has been deleted. When i searched over it, i got this Apple Doc. According to it, DocumentsDirectory should be the ideal place to store the User/Application data.
Put user data in the /Documents/. User data is any
data that cannot be recreated by your app, such as user documents and
other user-generated content.
And Cache should not be used to store the User Data that could not be reproduced by the application.
Put data cache files in the /Library/Caches
directory. Examples of files you should put in this directory include
(but are not limited to) database cache files and downloadable
content, such as that used by magazine, newspaper, and map apps. Your
app should be able to gracefully handle situations where cached data
is deleted by the system to free up disk space.
What should be the ideal place to store it.
EDIT:
I have an application that allows user to store Videos and Photos in the application. For that i used CacheDirectory. But i am getting bug reports that the Data (Videos/Photos) is getting deleted. What conclusion i draw is that the data is being getting delete by the Device itself in order to provide space.
Secondly i also wanna give the iTunes sharing function. So only the particular files has to be stored in the DocumentsDirectory. Some files can never be exposed and some has has to be shared. What should be the ideal way to store the files.
Use Documents (NSDocumentDirectory) for files you wish to share via iTunes.
Use Application Support (NSApplicationSupportDirectory) for files you wish to hide from the user but still be backed up and never deleted by the OS.
Starting iOS 5, Apple says that it's no longer a good thing to save all kind of files in Documents Directory - if you do that, your app will be rejected for sure because this folder is backed up to iTunes & iCloud, unless otherwise specified.
It says that we should save files into Caches or Tmp Directory - these won't be backed up, but it's not a good thing to do because files from these directories can disappear if low memory happens.
So I think the best think to do is to save the important files that you need all the time in your app into Documents Directory and mark them not to be backed up, like this.
Library/Application Support Folder is the folder you should be using.
This directory doesn't always exist, and thus you may need to create it.
You can enable or disable whether you want to backup this data with iTunes or not.
This data is not accessible even if you enable file sharing. Only data that you put in Document directory would be shared with iTunes sharing, so you can still protect your data and get it backed up as well. Apple's documentation
How can I actually backup my app document directory by using iCloud, so that user can switch over iCloud accounts and get his app data, related to that particular account.
And my document directory contains sqlite database file and images.
I just read the iOS Data Storage Guidelines,
To ensure that backups are as efficient as possible, store your app’s data according to the following guidelines:
Only documents and other data that is user-generated, or that cannot otherwise be recreated by your application, should be stored in the Application_Home/Documents directory and will be automatically backed up by iCloud.
Data that can be downloaded again or regenerated should be stored in the Application_Home/Library/Caches directory. Examples of files
you should put in the Caches directory include database cache files
and downloadable content, such as that used by magazine, newspaper,
and map applications.
Data that is used only temporarily should be stored in the Application_Home/tmp directory. Although these files are not backed
up to iCloud, remember to delete those files when you are done with
them so that they do not continue to consume space on the user’s
device.
Use the "do not back up" attribute for specifying files that should remain on device, even in low storage situations. Use this attribute
with data that can be recreated but needs to persist even in low
storage situations for proper functioning of your app or because
customers expect it to be available during offline use. This attribute
works on marked files regardless of what directory they are in,
including the Documents directory. These files will not be purged and
will not be included in the user's iCloud or iTunes backup. Because
these files do use on-device storage space, your app is responsible
for monitoring and purging these files periodically.
As per guidelines, Application_Home/Documents will be automatically backed up by iCloud.
References and useful links
https://developer.apple.com/icloud/documentation/data-storage/index.html
https://developer.apple.com/library/ios/documentation/DataManagement/Conceptual/UsingCoreDataWithiCloudPG/BestPractices/BestPractices.html
https://developer.apple.com/icloud/
Where exactly is the IsolatedStorage on the android devices. I would have expected it to be in the /mnt/sdcard/Android/data/[packagename]/ location, but it is not. I used the File Explorer (from eclipse) to try and find it, but I can't.
If I can somehow load a html page into the WebView or play a video from IsolatedStorage, then I won't need this actual path. But, I don't want to copy the movie to a temporary location in order to play it, I might as well just store it on the SD Card.
The reason I am using IsolatedStorage is to minimize the custom code across the platforms, I am developing for the Windows Phone, which only allows for IsolatedStorage.
To determine the directory in which your "isolated storage" aka internal storage is kept, use the GetFilesDir() method. This method is part of the Activity base class. It is to be used for files you do not want other applications to have access to.
Other useful methods
GetFilesDir():
Gets the absolute path to the filesystem directory where your internal files are saved.
GetDir():
Creates (or opens an existing) directory within your internal storage space.
DeleteFile():
Deletes a file saved on the internal storage.
FileList():
Returns an array of files currently saved by your application.
See the android developers documentation for more details
I found that IsolatedStorageFile points towards internal memory only.
I used the Context.GetFilesDir() and the Context.GetExternalFilesDir() depending on the user's selection.
I need to store some data files for my blackberry app. These are usually small png files that I download and store locally for performance reasons. Also I need to store an xml file locally.
My question is where are these files supposed to be saved on a blackberry? Is there such a thing as an application's home folder or settings folder in the blackberry filesystem?
What would be the path to such a folder?
This is for blackberry os 4.7 or later.
Thanks!
If it's not a huge amount of data (and by the sounds of it, it's not), take a look at the PersistentStore mechanism. You can store many types of data including native types (String, Integer, etc.) and even byte[] data (for images) using PersistentContent. The nice thing about PersistentStore is that it doesn't require any sort of filesystem access -- it doesn't leave files hanging around -- and if you include a custom class in the persistent store for your app (even a simple subclass of an existing persistible class such as Hashtable), it will automatically delete your persisted data if the app is deleted.
There's no official home folder for your application. In blackberry you can basically read/write just about anything/anywhere (well, you might get a SecurityException/IOException if you'll try do change some files).
You can write to the SDCard/Internal memory using the paths described here.
If you're worried about someone seeing and altering your data there's not much you can do except setting your files and directories as hidden using FileConnection.setHidden(true) but this is very lame since they can still be seen even from the native BlackBerry file browser if the user chooses to show hidden files from the menu.
Edit: You could of course encrypt/decrypt your data but this won't prevent someone from deleting it.