我怎样才能让哑剧类型的文件有它的 Uri？

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最佳答案

You can try

ContentResolver cR = context.getContentResolver();
MimeTypeMap mime = MimeTypeMap.getSingleton();
String type = mime.getExtensionFromMimeType(cR.getType(uri));

Edit :

mime.getExtensionFromMimeType(cR.getType(uri))

returns -> "jpeg"

cR.getType(uri);

returns "image/jpeg" that is the expected value.

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Instead of this:

String type = mime.getExtensionFromMimeType(cR.getType(uri));

Do this:

String type = cR.getType(uri);

And you will get this: image/jpeg.

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This method returns the extension of the file (jpg, png, pdf, epub etc..).

 public static String getMimeType(Context context, Uri uri) {
String extension;


//Check uri format to avoid null
if (uri.getScheme().equals(ContentResolver.SCHEME_CONTENT)) {
//If scheme is a content
final MimeTypeMap mime = MimeTypeMap.getSingleton();
extension = mime.getExtensionFromMimeType(context.getContentResolver().getType(uri));
} else {
//If scheme is a File
//This will replace white spaces with %20 and also other special characters. This will avoid returning null values on file name with spaces and special characters.
extension = MimeTypeMap.getFileExtensionFromUrl(Uri.fromFile(new File(uri.getPath())).toString());


}


return extension;
}

小开

for Content Uri.

ContentResolver cr = context.getContentResolver();
mimeType = cr.getType(contentUri);

for File Uri.

String fileExtension = MimeTypeMap.getFileExtensionFromUrl(fileUri
.toString());
mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension(
fileExtension.toLowerCase());

for Both, works for Content as well as File.

public String getMimeType(Context context, Uri uri) {
String mimeType = null;
if (ContentResolver.SCHEME_CONTENT.equals(uri.getScheme())) {
ContentResolver cr = context.getContentResolver();
mimeType = cr.getType(uri);
} else {
String fileExtension = MimeTypeMap.getFileExtensionFromUrl(uri
.toString());
mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension(
fileExtension.toLowerCase());
}
return mimeType;
}

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I will parrot the answer of Bhavesh with Kotlin extension and return type of okhttp3.MediaType:

fun Uri.mimeType(contentResolver: ContentResolver)
: MediaType? {
if (scheme.equals(ContentResolver.SCHEME_CONTENT)) {
// get (image/jpeg, video/mp4) from ContentResolver if uri scheme is "content://"
return contentResolver.getType(this)?.toMediaTypeOrNull()
} else {
// get (.jpeg, .mp4) from uri "file://example/example.mp4"
val fileExtension = MimeTypeMap.getFileExtensionFromUrl(toString())
// turn ".mp4" into "video/mp4"
return MimeTypeMap.getSingleton()
.getMimeTypeFromExtension(fileExtension.toLowerCase(Locale.US))
?.toMediaTypeOrNull()
}
}

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Return "image/jpeg" for example

fun Uri.getMimeType(context: Context): String? {
return when (scheme) {
ContentResolver.SCHEME_CONTENT -> context.contentResolver.getType(this)
ContentResolver.SCHEME_FILE -> MimeTypeMap.getSingleton().getMimeTypeFromExtension(
MimeTypeMap.getFileExtensionFromUrl(toString()).toLowerCase(Locale.US)
)
else -> null
}
}

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for kotlin this function will work

fun getMime(uri : Uri, context: Context) : String?{
val cr = context.contentResolver
return cr.getType(uri)
}