As a rule of thumb, Xamarin. Android apps should prefer saving their files on internal storage when it is reasonable, and rely on external storage when files need to be shared with other apps, are very large, or should be retained even if the app is uninstalled. For example, a configuration file is best suited for a internal storage as it has no importance except to the app that creates it.
In contrast, photos are a good candidate for external storage. They can be very large and in many cases the user may want to share them or access them even if the app is uninstalled. This guide will focus on internal storage. Please see the guide External storage for details on using external storage in a Xamarin. Android application. The internal storage directory for an application is determined by the operating system, and is exposed to Android apps by the Android.
FilesDir property. This will return a Java. File object representing the directory that Android has dedicated exclusively for the app. For example, an app with the package name com. The exact path to the internal storage directory can vary from device to device and between versions of Android. Because of this, apps must not hard code the path to the internal files storage directory, and instead use the Xamarin.
Android APIs, such as System. To maximize code sharing, Xamarin. Android apps or Xamarin. Forms apps targeting Xamarin. Android should use the System. GetFolderPath method. In Xamarin. Android, this method will return a string for a directory that is the same location as Android. I create an interface to achieve it in PCL. Combine Android. AbsolutePath, Android. GetFolderPath System. Exists file. Open "test. Write bytes ; outs.
Flush ; outs. Toolbar; base. OnCreate savedInstanceState ; Rg. Init this, savedInstanceState ; Xamarin. Init this, savedInstanceState ; global::Xamarin. Wednesday, September 30, AM. User posted Thank you very much for your answer LeonLu, in reality what was missing for me was: if ContextCompat. Thank you anyway. Private files — Private files are files that are specific to your application but are still world-readable and world-writable.
Android expects that private files are stored in a specific directory on external storage. Even though the files are called "private", they are still visible and accessible by other apps on the device, they are not afforded any special protection by Android.
Public files — These are files that are not considered to be specific to the application and are meant to be freely shared. The differences between these files is primarily conceptual. Private files are private in the sense that they are considered to be a part of the application, while public files are any other files that exist on external storage.
Android provides two different APIs for resolving the paths to private and public files, but otherwise the same. These are the same APIs that are discussed in the section on reading and writing. Private external files are considered to be specific to an application similar to internal files but are being kept on external storage for any number of reasons such as being too large for internal storage.
Similar to internal files, these files will be deleted when the app is uninstalled by the user. The primary location for private external files is found by calling the method Android. GetExternalFilesDir string type. This method will return a Java. File object that represents the private external storage directory for the app. Passing null to this method will return the path to the user's storage directory for the application. As an example, for an application with the package name com.
The parameter for GetExternalFilesDir is a string that specifies an application directory. This is a directory intended to provide a standard location for a logical organization of files. The string values are available through constants on the Android. Environment class:. For devices that have multiple external storage partitions, each partition will have a directory that is intended for private files.
The method Android. GetExternalFilesDirs string type will return an array of Java. The exact path to the private external storage directory can vary from device to device and between versions of Android.
Because of this, apps must not hard code the path to this directory, and instead use the Xamarin. Android APIs, such as Android. The reason for this that the user will then not have to scroll through folder after folder to find the file. Hope that makes it clearer. The content you requested has been removed.
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