Android file add path

Learn how to use fileprovider in Android with example

Today we will be looking at the one of the confusing topic in android i.e. FileProvider. It is confusing for beginners as they do not understand, how to use it and why to use it. So let us learn how to use FileProvider in Android with an example project.

If you just want to get file path from internal document picker check out this article: here.

What is a FileProvider in Android ?

How long have you been exploring this concept of file provider in android ? I think it’s been quite a while but you have not found a easier explanation about it. Here I will simply explain what a fileprovider is and why even bother with it in the first place ?

FileProvider is simply a special subclass of ContentProvider which allows manipulating user data on storage more secure and easy ( not really at first ). It simply creates a content:/// URI instead of file:/// which makes secure.

How does it make the files accessing more secure ? To answer that question we must understand that using the FileProvider only a content:/// is exposed meaning the actual file location is hidden, and adds security.

But adding security means some headaches for developers especially for someone who is just starting with the Android Development. I will break down BITS of FileProvider below so let us continue.

Using FileProvider in Android application

Let us see how we can use the FileProvider in our application step by step.

Setting up FileProvider in manifest

Let us see how we can add the FileProvider definition in out manifest file. Add the code below in your AndroidManifest.xml file.

Creating file_paths.xml file to add our file paths

Now that we have added the FileProvider definition in our AndroidManifest.xml let us look at the code.

You will receive an error at the code above because we have to mention the path for the FileProvider to access. Which we will do below but first lets create an Android resource directory.

Go to projects side bar and navigate to app > res . Right click there and click Android Resource Directory . name the directory xml and select xml from drop down.

After that create the file_paths.xml in the xml directory and add the contents below.

Confused about what the code above means ? Don’t be because I will break everything down.

Understanding what each file path actually mean

Now we have to understand something before proceeding. Everything is scoped with file paths. Meaning accessing anything outside defined file paths will cause a runtime exception.

Each type of paths you see between

serve a purpose. And we are going to learn what that is with this fileprovider Android example.

Note: name and path is same for each. where name is the pointer and path is the actual location.

This is the path will will be accessible by invoking this method Context.getFilesDir() . We will get a file instance pointing to the files dir. This directory is located in the internal storage area on your device.

Same as above the only difference is it resides in the external removable storage area of the device. The root path is returned by Context.getExternalFilesDir(null) .

/>

This is same as files-path but it provides the root directory for internal area cache. Which is what you get when you invoke Context.getCacheDir() .

Same as the the local cache but the difference is the cache directory is located in external storage area. Which you will get once you use Context.getExternalCacheDir().

This path also defines the media directory located on the external storage area of your device. Which returns the path provided by Context.getExternalMediaDirs() . But this method is deprecated and MediaStore must be used.

This path is relative to the external root of your device. And you can get this file by Environment.getExternalStorageDirectory() . As you normally would, this method is marked deprecated and must not be used normally. Always use file providers for any file reading.

Getting the content URI

Now that we have understood what each means. Let us move forward and retrieve out URI, as it was our main goal.

We have set everything up let us create a temporary file in our cache directory. Let us write the code in out MainActivity as

Now that will create a file named test_file.txt in our cache directory, remember ?

Next we will update the URI into our TextView just to make sure it worked.

Look at the FILE_AUTHORITY which we have declared in the companion object block. The full code for MainActivity is provided below:

Sharing the URI using ShareCompat.IntentBuilder

Let us explore how we can share the URI using the ShareCompat.IntentBuilder here.

This will open up the possible applications for image/jpg , you can change that as per your need.

Now we are done. What you do with the URI is up to you. Next time we will learn how to get the actual file from URI. Till then, keep learning.

For reference you can checkout official documentation, here.

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How To Set Android SDK Path In Windows And Mac

After you installed android studio, you still need to configure some android SDK environment variables then you can use it easily. This article will tell you how to correctly configure Android SDK environment variables such as ANDROID_HOME, PATH on Windows and macOS.

1. Configure Android SDK Variable In Windows.

1.1 Get Android SDK Install Directory Path.

Before you can configure it, you should first get the android SDK install directory follow below steps.

1. Open android studio, click File —> Settings menu item in the top men bar.
2. Expand Appearance & Behavior —>System Settings —>Android SDK menu item on the left side of the popup window. Then you can find the Android SDK Location directory path on the right side ( in this example, the Android SDK location path is C:\Users\Jerry\AppData\Local\Android\Sdk ), remember it.

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1.2 Set %ANDROID_HOME% and %Path% System Environment Variable.

1. Right-click the computer icon in Windows file explorer left side, click Properties menu item in the popup menu list. This will open the windows system configuration window.
2. Click the Advanced system settings link on left panel, it will popup the System Properties window, click the Environment Variables button to open Environment Variables window.
3. Click the New… button to add a new system variable, input ANDROID_HOME as the variable name, and input the Android SDK location directory path ( such as C:\Users\Administrator\AppData\Local\Android\Sdk ) as the variable value.
4. Select variable Path and click Edit button and add ;%ANDROID_HOME%\tools;%ANDROID_HOME%\tools\bin;%ANDROID_HOME%\platform-tools at the end of its value. Please note the ; must be English character otherwise it will not take effect .
5. Click OK to close the system environment variables settings window, open a dos window, type command adb in it. If you see output like below that means the android SDK path variable has been configured successfully.

2. Configure Android SDK Variable In macOS.

1. Open Android Studio on macOS, then click Android Studio —> Preferences menu item at the left top toolbar.
2. Input search keyword sdk in the search box of the popup Preferences dialog window left side.
3. It will focus on the Android SDK menu item on the left side, and you can get the Android SDK Location directory path value on the right side Android SDK Location text box.
4. Generally, the Android SDK is installed in the /Users/user-name/Library/Android/sdk folder on macOS.
5. If you can not find the above folder in macOS finder or terminal, this is because the Library folder is a hidden folder by default, you should make the hidden folder visible by executing the command $ defaults write com. apple . finder AppleShowAllFiles TRUE in a macOS terminal window ( please read article How To Show Hidden Files In Mac OS Finder And Select Hidden Files In Html Upload File Form ).
6. You can also see the hidden Library folder by opening a macOS Finder window, then click Go —> Go to Folder… menu item, and input

/Library in the popup dialog input text box, then click Go button.

This is also another method to show the hidden Library folder, open a macOS Finder window, click Go —> Home menu item. Right-click the home folder, then click the Show View Options menu item in the popup menu list. Check the Show Library Folder checkbox.

Use nano to create or edit user bash profile in user home directory.

Add ANDROID_HOME and PATH environment variable in user bash profile.

Make the added system environment take effect.

Now open a terminal and run adb, you should also see something output like in windows.

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Access media files from shared storage

To provide a more enriched user experience, many apps allow users to contribute and access media that’s available on an external storage volume. The framework provides an optimized index into media collections, called the media store, that allows for retrieving and updating these media files more easily. Even after your app is uninstalled, these files remain on the user’s device.

To interact with the media store abstraction, use a ContentResolver object that you retrieve from your app’s context:

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The system automatically scans an external storage volume and adds media files to the following well-defined collections:

• Images, including photographs and screenshots, which are stored in the DCIM/ and Pictures/ directories. The system adds these files to the MediaStore.Images table.
• Videos, which are stored in the DCIM/ , Movies/ , and Pictures/ directories. The system adds these files to the MediaStore.Video table.
• Audio files, which are stored in the Alarms/ , Audiobooks/ , Music/ , Notifications/ , Podcasts/ , and Ringtones/ directories. Additionally, the system recognizes audio playlists that are in the Music/ or Movies/ directories, as well as voice recordings that are in the Recordings/ directory. The system adds these files to the MediaStore.Audio table. The recordings directory isn’t available on Android 11 (API level 30) and lower.
• Downloaded files, which are stored in the Download/ directory. On devices that run Android 10 (API level 29) and higher, these files are stored in the MediaStore.Downloads table. This table isn’t available on Android 9 (API level 28) and lower.

The media store also includes a collection called MediaStore.Files . Its contents depend on whether your app uses scoped storage, available on apps that target Android 10 or higher:

• If scoped storage is enabled, the collection shows only the photos, videos, and audio files that your app has created. Most developers won’t need to use MediaStore.Files to view media files from other apps, but if you have a specific requirement to do so, you can declare the READ_EXTERNAL_STORAGE permission. It’s recommended, however, that you use the MediaStore APIs to open files that your app hasn’t created.
• If scoped storage is unavailable or not being used, the collection shows all types of media files.

Request necessary permissions

Before performing operations on media files, make sure your app has declared the permissions that it needs to access these files. Keep in mind, however, that your app shouldn’t declare permissions that it doesn’t need or use.

Storage permission

The permissions model for accessing media files in your app depends on whether your app uses scoped storage, available on apps that target Android 10 or higher.

Scoped storage enabled

If your app uses scoped storage, it should request storage-related permissions only for devices that run Android 9 (API level 28) or lower. You can apply this condition by adding the android:maxSdkVersion attribute to the permission declaration in your app’s manifest file:

Don’t unnecessarily request storage-related permissions for devices that run Android 10 or higher. Your app can contribute to well-defined media collections, including the MediaStore.Downloads collection, without requesting any storage-related permissions. If you’re developing a camera app, for example, you don’t need to request storage-related permissions because your app owns the images that you’re writing to the media store.

To access files that other apps have created, the following conditions must each be true:

If your app wants to access a file within the MediaStore.Downloads collection that your app didn’t create, you must use the Storage Access Framework. To learn more about how to use this framework, see the guide on how to access documents and other files.

Scoped storage unavailable

If your app is used on a device that runs Android 9 or lower, or if your app has temporarily opted out of scoped storage, you must request the READ_EXTERNAL_STORAGE permission to access media files. If you want to modify media files, you must request the WRITE_EXTERNAL_STORAGE permission, as well.

Media location permission

If your app targets Android 10 (API level 29) or higher, in order for your app to retrieve unredacted Exif metadata from photos, you need to declare the ACCESS_MEDIA_LOCATION permission in your app’s manifest, then request this permission at runtime.

Check for updates to the media store

To access media files more reliably, particularly if your app caches URIs or data from the media store, check whether the media store version has changed compared to when you last synced your media data. To perform this check for updates, call getVersion() . The returned version is a unique string that changes whenever the media store changes substantially. If the returned version is different from the last synced version, rescan and resync your app’s media cache.

Complete this check at app process startup time. There’s no need to check the version each time you query the media store.

Don’t assume any implementation details regarding the version number.

Query a media collection

To find media that satisfies a particular set of conditions, such as a duration of 5 minutes or longer, use an SQL-like selection statement similar to the one shown in the following code snippet:

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When performing such a query in your app, keep the following in mind:

• Call the query() method in a worker thread.
• Cache the column indices so that you don’t need to call getColumnIndexOrThrow() each time you process a row from the query result.
• Append the ID to the content URI, as shown in the code snippet.
• Devices that run Android 10 and higher require column names that are defined in the MediaStore API. If a dependent library within your app expects a column name that’s undefined in the API, such as «MimeType» , use CursorWrapper to dynamically translate the column name in your app’s process.

Load file thumbnails

If your app shows multiple media files and requests that the user choose one of these files, it’s more efficient to load preview versions—or thumbnails—of the files instead of the files themselves.

To load the thumbnail for a given media file, use loadThumbnail() and pass in the size of the thumbnail that you want to load, as shown in the following code snippet:

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Open a media file

The specific logic that you use to open a media file depends on whether the media content is best represented as a file descriptor, a file stream, or a direct file path:

File descriptor

To open a media file using a file descriptor, use logic similar to that shown in the following code snippet:

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File stream

To open a media file using a file stream, use logic similar to that shown in the following code snippet:

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Direct file paths

To help your app work more smoothly with third-party media libraries, Android 11 (API level 30) and higher allow you to use APIs other than the MediaStore API to access media files from shared storage. You can instead access media files directly using either of the following APIs:

• The File API.
• Native libraries, such as fopen() .

If you don’t have any storage-related permissions, you can access files in your app-specific directory, as well as media files that are attributed to your app, using the File API.

If your app tries to access a file using the File API and it doesn’t have the necessary permissions, a FileNotFoundException occurs.

To access other files in shared storage on a device that runs Android 10 (API level 29), it’s recommended that you temporarily opt out of scoped storage by setting requestLegacyExternalStorage to true in your app’s manifest file. In order to access media files using native files methods on Android 10, you must also request the READ_EXTERNAL_STORAGE permission.

Considerations when accessing media content

When accessing media content, keep in mind the considerations discussed in the following sections.

Cached data

If your app caches URIs or data from the media store, periodically check for updates to the media store. This check allows your app-side, cached data to stay in sync with the system-side, provider data.

Performance

When you perform sequential reads of media files using direct file paths, the performance is comparable to that of the MediaStore API.

When you perform random reads and writes of media files using direct file paths, however, the process can be up to twice as slow. In these situations, we recommend using the MediaStore API instead.

DATA column

When you access an existing media file, you can use the value of the DATA column in your logic. That’s because this value has a valid file path. However, don’t assume that the file is always available. Be prepared to handle any file-based I/O errors that could occur.

To create or update a media file, on the other hand, don’t use the value of the DATA column. Instead, use the values of the DISPLAY_NAME and RELATIVE_PATH columns.

Storage volumes

Apps that target Android 10 or higher can access the unique name that the system assigns to each external storage volume. This naming system helps you efficiently organize and index content, and it gives you control over where new media files are stored.

The following volumes are particularly useful to keep in mind:

• The VOLUME_EXTERNAL volume provides a view of all shared storage volumes on the device. You can read the contents of this synthetic volume, but you cannot modify the contents.
• The VOLUME_EXTERNAL_PRIMARY volume represents the primary shared storage volume on the device. You can read and modify the contents of this volume.

You can discover other volumes by calling MediaStore.getExternalVolumeNames() :

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Location where media was captured

Some photographs and videos contain location information in their metadata, which shows the place where a photograph was taken or where a video was recorded.

To access this location information in your app, use one API for photograph location information and another API for video location information.

Photographs

If your app uses scoped storage, the system hides location information by default. To access this information, complete the following steps:

Request the ACCESS_MEDIA_LOCATION permission in your app’s manifest.

From your MediaStore object, get the exact bytes of the photograph by calling setRequireOriginal() and pass in the URI of the photograph, as shown in the following code snippet:

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Videos

To access location information within a video’s metadata, use the MediaMetadataRetriever class, as shown in the following code snippet. Your app doesn’t need to request any additional permissions to use this class.

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Sharing

Some apps allow users to share media files with each other. For example, social media apps give users the ability to share photos and videos with friends.

To share media files, use a content:// URI, as recommended in the guide to creating a content provider.

App attribution of media files

When scoped storage is enabled for an app that targets Android 10 or higher, the system attributes an app to each media file, which determines the files that your app can access when it hasn’t requested any storage permissions. Each file can be attributed to only one app. Therefore, if your app creates a media file that’s stored in the photos, videos, or audio files media collection, your app has access to the file.

If the user uninstalls and reinstalls your app, however, you must request READ_EXTERNAL_STORAGE to access the files that your app originally created. This permission request is required because the system considers the file to be attributed to the previously-installed version of the app, rather than the newly-installed one.

Add an item

To add a media item to an existing collection, call code similar to the following. This code snippet accesses the VOLUME_EXTERNAL_PRIMARY volume on devices that run Android 10 or higher. That’s because, on these devices, you can only modify the contents of a volume if it’s the primary volume, as described in the storage volumes section.

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Toggle pending status for media files

If your app performs potentially time-consuming operations, such as writing to media files, it’s useful to have exclusive access to the file as it’s being processed. On devices that run Android 10 or higher, your app can get this exclusive access by setting the value of the IS_PENDING flag to 1. Only your app can view the file until your app changes the value of IS_PENDING back to 0.

The following code snippet builds upon the previous code snippet. The following snippet shows how to use the IS_PENDING flag when storing a long song in the directory corresponding to the MediaStore.Audio collection:

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Give a hint for file location

When your app stores media on a device running Android 10, the media is organized based on its type by default. For example, new image files are placed by default in the Environment.DIRECTORY_PICTURES directory, which corresponds to the MediaStore.Images collection.

If your app is aware of a specific location where files should be stored, such as a photo album called Pictures/MyVacationPictures, you can set MediaColumns.RELATIVE_PATH to provide the system a hint for where to store the newly-written files.

Update an item

To update a media file that your app owns, run code similar to the following:

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If scoped storage is unavailable or not enabled, the process shown in the preceding code snippet also works for files that your app doesn’t own.

Update in native code

If you need to write media files using native libraries, pass the file’s associated file descriptor from your Java-based or Kotlin-based code into your native code.

The following code snippet shows how to pass a media object’s file descriptor into your app’s native code:

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Update other apps’ media files

If your app uses scoped storage, it ordinarily cannot update a media file that a different app contributed to the media store.

It’s still possible to get user consent to modify the file, however, by catching the RecoverableSecurityException that the platform throws. You can then request that the user grant your app write access to that specific item, as shown in the following code snippet:

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Complete this process each time your app needs to modify a media file that it didn’t create.

Alternatively, if your app runs on Android 11 or higher, you can allow users to grant your app write access to a group of media files. Call the createWriteRequest() method, as described in the section on how to manage groups of media files.

If your app has another use case that isn’t covered by scoped storage, file a feature request and temporarily opt out of scoped storage.

Remove an item

To remove an item that your app no longer needs in the media store, use logic similar to what’s shown in the following code snippet:

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If scoped storage is unavailable or isn’t enabled, you can use the preceding code snippet to remove files that other apps own. If scoped storage is enabled, however, you need to catch a RecoverableSecurityException for each file that your app wants to remove, as described in the section on updating media items.

If your app runs on Android 11 or higher, you can allow users to choose a group of media files to remove. Call the createTrashRequest() method or the createDeleteRequest() method, as described in the section on how to manage groups of media files.

If your app has another use case that isn’t covered by scoped storage, file a feature request and temporarily opt out of scoped storage.

Detect updates to media files

Your app might need to identify storage volumes containing media files that apps added or modified, compared to a previous point in time. To detect these changes most reliably, pass the storage volume of interest into getGeneration() . As long as the media store version doesn’t change, the return value of this method monotonically increases over time.

In particular, getGeneration() is more robust than the dates in media columns, such as DATE_ADDED and DATE_MODIFIED . That’s because those media column values could change when an app calls setLastModified() , or when the user changes the system clock.

Manage groups of media files

On Android 11 and higher, you can ask the user to select a group of media files, then update these media files in a single operation. These methods offer better consistency across devices, and the methods make it easier for users to manage their media collections.

The methods that provide this «batch update» functionality include the following:

createWriteRequest() Request that the user grant your app write access to the specified group of media files. createFavoriteRequest() Request that the user marks the specified media files as some of their «favorite» media on the device. Any app that has read access to this file can see that the user has marked the file as a «favorite». createTrashRequest()

Request that the user place the specified media files in the device’s trash. Items in the trash are permanently deleted after a system-defined time period.

Request that the user permanently delete the specified media files immediately, without placing them in the trash beforehand.

After calling any of these methods, the system builds a PendingIntent object. After your app invokes this intent, users see a dialog that requests their consent for your app to update or delete the specified media files.

For example, here is how to structure a call to createWriteRequest() :

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Evaluate the user’s response. If the user provided consent, proceed with the media operation. Otherwise, explain to the user why your app needs the permission:

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Media management permission

Users might trust a particular app to perform media management, such as making frequent edits to media files. If your app targets Android 11 or higher and isn’t the device’s default gallery app, you must show a confirmation dialog to the user each time your app attempts to modify or delete a file.

If your app targets Android 12 (API level 31) or higher, you can request that users grant your app access to the Media management special permission. This permission allows your app to do each of the following without needing to prompt the user for each file operation:

To do so, complete the following steps:

Declare the MANAGE_MEDIA permission and the READ_EXTERNAL_STORAGE permission in your app’s manifest file.

In order to call createWriteRequest() without showing a confirmation dialog, declare the ACCESS_MEDIA_LOCATION permission as well.

In your app, show a UI to the user to explain why they might want to grant media management access to your app.

Invoke the ACTION_REQUEST_MANAGE_MEDIA intent action. This takes users to the Media management apps screen in system settings. From here, users can grant the special app access.

Use cases that require an alternative to media store

If your app primarily performs one of the following roles, consider an alternative to the MediaStore APIs.

Work with other types of files

If your app works with documents and files that don’t exclusively contain media content, such as files that use the EPUB or PDF file extension, use the ACTION_OPEN_DOCUMENT intent action, as described in the guide on how to store and access documents and other files.

File sharing in companion apps

In cases where you provide a suite of companion apps—such as a messaging app and a profile app—set up file sharing using content:// URIs. We also recommend this workflow as a security best practice.

Additional resources

For more information about how to store and access media, consult the following resources.

Samples

Videos

Content and code samples on this page are subject to the licenses described in the Content License. Java is a registered trademark of Oracle and/or its affiliates.

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