什么是最简单的方法从android.net.Uri对象持有一个文件:类型转换为java.io.File对象在Android?
我尝试了下面的方法,但不管用:
File file = new File(Environment.getExternalStorageDirectory(), "read.me");
Uri uri = Uri.fromFile(file);
File auxFile = new File(uri.toString());
assertEquals(file.getAbsolutePath(), auxFile.getAbsolutePath());
我是这样做的:
try {
readImageInformation(new File(contentUri.getPath()));
} catch (IOException e) {
readImageInformation(new File(getRealPathFromURI(context,
contentUri)));
}
public static String getRealPathFromURI(Context context, Uri contentUri) {
String[] proj = { MediaStore.Images.Media.DATA };
Cursor cursor = context.getContentResolver().query(contentUri, proj,
null, null, null);
int column_index = cursor
.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}
所以基本上首先我尝试使用一个文件,即相机拍摄的照片,并保存在SD卡上。这对返回的图像不起作用:
意图photoPickerIntent =新的意图(Intent. action_pick);
在这种情况下,需要通过getRealPathFromURI()函数将Uri转换为真实路径。
所以结论是,这取决于你想转换为File的Uri类型。
你可以使用这个函数从uri中获取文件在新的android和旧的
fun getFileFromUri(context: Context, uri: Uri?): File? {
uri ?: return null
uri.path ?: return null
var newUriString = uri.toString()
newUriString = newUriString.replace(
"content://com.android.providers.downloads.documents/",
"content://com.android.providers.media.documents/"
)
newUriString = newUriString.replace(
"/msf%3A", "/image%3A"
)
val newUri = Uri.parse(newUriString)
var realPath = String()
val databaseUri: Uri
val selection: String?
val selectionArgs: Array<String>?
if (newUri.path?.contains("/document/image:") == true) {
databaseUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI
selection = "_id=?"
selectionArgs = arrayOf(DocumentsContract.getDocumentId(newUri).split(":")[1])
} else {
databaseUri = newUri
selection = null
selectionArgs = null
}
try {
val column = "_data"
val projection = arrayOf(column)
val cursor = context.contentResolver.query(
databaseUri,
projection,
selection,
selectionArgs,
null
)
cursor?.let {
if (it.moveToFirst()) {
val columnIndex = cursor.getColumnIndexOrThrow(column)
realPath = cursor.getString(columnIndex)
}
cursor.close()
}
} catch (e: Exception) {
Log.i("GetFileUri Exception:", e.message ?: "")
}
val path = realPath.ifEmpty {
when {
newUri.path?.contains("/document/raw:") == true -> newUri.path?.replace(
"/document/raw:",
""
)
newUri.path?.contains("/document/primary:") == true -> newUri.path?.replace(
"/document/primary:",
"/storage/emulated/0/"
)
else -> return null
}
}
return if (path.isNullOrEmpty()) null else File(path)
}