ContentResolver.OpenAssetFileDescriptor Method
Definition
Important
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Overloads
| OpenAssetFileDescriptor(Uri, String) |
Open a raw file descriptor to access data under a URI. |
| OpenAssetFileDescriptor(Uri, String, CancellationSignal) |
Open a raw file descriptor to access data under a URI. |
OpenAssetFileDescriptor(Uri, String)
Open a raw file descriptor to access data under a URI.
[Android.Runtime.Register("openAssetFileDescriptor", "(Landroid/net/Uri;Ljava/lang/String;)Landroid/content/res/AssetFileDescriptor;", "")]
public Android.Content.Res.AssetFileDescriptor? OpenAssetFileDescriptor (Android.Net.Uri uri, string mode);[<Android.Runtime.Register("openAssetFileDescriptor", "(Landroid/net/Uri;Ljava/lang/String;)Landroid/content/res/AssetFileDescriptor;", "")>]
member this.OpenAssetFileDescriptor : Android.Net.Uri * string -> Android.Content.Res.AssetFileDescriptorParameters
- uri
- Uri
The desired URI to open.
- mode
- String
The string representation of the file mode. Can be "r", "w", "wt", "wa", "rw" or "rwt". Please note the exact implementation of these may differ for each Provider implementation - for example, "w" may or may not truncate.
Returns
Returns a new ParcelFileDescriptor pointing to the file or null if the
provider recently crashed. You own this descriptor and are responsible for closing it
when done.
- Attributes
Exceptions
Throws FileNotFoundException of no file exists under the URI or the mode is invalid.
Remarks
Open a raw file descriptor to access data under a URI. This interacts with the underlying ContentProvider#openAssetFile method of the provider associated with the given URI, to retrieve any file stored there.
<h5>Accepts the following URI schemes:</h5> <ul> <li>content (#SCHEME_CONTENT)</li> <li>android.resource (#SCHEME_ANDROID_RESOURCE)</li> <li>file (#SCHEME_FILE)</li> </ul> <h5>The android.resource (#SCHEME_ANDROID_RESOURCE) Scheme</h5>
A Uri object can be used to reference a resource in an APK file. The Uri should be one of the following formats: <ul> <li>android.resource://package_name/id_number<br/> package_name is your package name as listed in your AndroidManifest.xml. For example com.example.myapp<br/> id_number is the int form of the ID.<br/> The easiest way to construct this form is
Uri uri = Uri.parse("android.resource://com.example.myapp/" + R.raw.my_resource");
</li> <li>android.resource://package_name/type/name<br/> package_name is your package name as listed in your AndroidManifest.xml. For example com.example.myapp<br/> type is the string form of the resource type. For example, raw or drawable. name is the string form of the resource name. That is, whatever the file name was in your res directory, without the type extension. The easiest way to construct this form is
Uri uri = Uri.parse("android.resource://com.example.myapp/raw/my_resource");
</li> </ul>
Note that if this function is called for read-only input (mode is "r") on a content: URI, it will instead call #openTypedAssetFileDescriptor for you with a MIME type of "*/*". This allows such callers to benefit from any built-in data conversion that a provider implements.
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.
Applies to
OpenAssetFileDescriptor(Uri, String, CancellationSignal)
Open a raw file descriptor to access data under a URI.
[Android.Runtime.Register("openAssetFileDescriptor", "(Landroid/net/Uri;Ljava/lang/String;Landroid/os/CancellationSignal;)Landroid/content/res/AssetFileDescriptor;", "")]
public Android.Content.Res.AssetFileDescriptor? OpenAssetFileDescriptor (Android.Net.Uri uri, string mode, Android.OS.CancellationSignal? cancellationSignal);[<Android.Runtime.Register("openAssetFileDescriptor", "(Landroid/net/Uri;Ljava/lang/String;Landroid/os/CancellationSignal;)Landroid/content/res/AssetFileDescriptor;", "")>]
member this.OpenAssetFileDescriptor : Android.Net.Uri * string * Android.OS.CancellationSignal -> Android.Content.Res.AssetFileDescriptorParameters
- uri
- Uri
The desired URI to open.
- mode
- String
The string representation of the file mode. Can be "r", "w", "wt", "wa", "rw"
or "rwt". Please note "w" is write only and "wt" is write and truncate.
SeeParcelFileDescriptor#parseMode for more details.
- cancellationSignal
- CancellationSignal
A signal to cancel the operation in progress, or null if
none. If the operation is canceled, then
OperationCanceledException will be thrown.
Returns
Returns a new ParcelFileDescriptor pointing to the file or null if the
provider recently crashed. You own this descriptor and are responsible for closing it
when done.
- Attributes
Exceptions
Throws FileNotFoundException of no file exists under the URI or the mode is invalid.
Remarks
Open a raw file descriptor to access data under a URI. This interacts with the underlying ContentProvider#openAssetFile method of the provider associated with the given URI, to retrieve any file stored there.
<h5>Accepts the following URI schemes:</h5> <ul> <li>content (#SCHEME_CONTENT)</li> <li>android.resource (#SCHEME_ANDROID_RESOURCE)</li> <li>file (#SCHEME_FILE)</li> </ul> <h5>The android.resource (#SCHEME_ANDROID_RESOURCE) Scheme</h5>
A Uri object can be used to reference a resource in an APK file. The Uri should be one of the following formats: <ul> <li>android.resource://package_name/id_number<br/> package_name is your package name as listed in your AndroidManifest.xml. For example com.example.myapp<br/> id_number is the int form of the ID.<br/> The easiest way to construct this form is
Uri uri = Uri.parse("android.resource://com.example.myapp/" + R.raw.my_resource");
</li> <li>android.resource://package_name/type/name<br/> package_name is your package name as listed in your AndroidManifest.xml. For example com.example.myapp<br/> type is the string form of the resource type. For example, raw or drawable. name is the string form of the resource name. That is, whatever the file name was in your res directory, without the type extension. The easiest way to construct this form is
Uri uri = Uri.parse("android.resource://com.example.myapp/raw/my_resource");
</li> </ul>
Note that if this function is called for read-only input (mode is "r") on a content: URI, it will instead call #openTypedAssetFileDescriptor for you with a MIME type of "*/*". This allows such callers to benefit from any built-in data conversion that a provider implements.
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.