MediaStore.GetGeneration(Context, String) Method
Definition
Important
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Return the latest generation value for the given volume.
[Android.Runtime.Register("getGeneration", "(Landroid/content/Context;Ljava/lang/String;)J", "", ApiSince=30)]
public static long GetGeneration(Android.Content.Context context, string volumeName);[<Android.Runtime.Register("getGeneration", "(Landroid/content/Context;Ljava/lang/String;)J", "", ApiSince=30)>]
static member GetGeneration : Android.Content.Context * string -> int64Parameters
- context
- Context
The context whose content resolver sends the media-provider request.
- volumeName
- String
specific volume to obtain an generation value for. Must
be one of the values returned from
#getExternalVolumeNames(Context).
Returns
The generation counter returned by the media provider for the specified volume.
- Attributes
Remarks
Return the latest generation value for the given volume.
Generation numbers are useful for apps that are attempting to quickly identify exactly which media items have been added or changed since a previous point in time. Generation numbers are monotonically increasing over time, and can be safely arithmetically compared.
Detecting media changes using generation numbers is more robust than using MediaColumns#DATE_ADDED or MediaColumns#DATE_MODIFIED, since those values may change in unexpected ways when apps use File#setLastModified(long) or when the system clock is set incorrectly.
Note that before comparing these detailed generation values, you should first confirm that the overall version hasn't changed by checking MediaStore#getVersion(Context, String), since that indicates when a more radical change has occurred. If the overall version changes, you should assume that generation numbers have been reset and perform a full synchronization pass.
Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.