如何在Android 10以上版本中使用MediaStore编辑文件而不是创建新文件? [英] How to edit a file instead of creating a new one using MediaStore above Android 10?

问题描述

我尝试使用带有以上代码的MediaStore在文档"外部目录中创建文件:

I've tried to create a file in Documents external directory using MediaStore with the above code :

        val resolver = applicationContext.contentResolver
        val contentValues = ContentValues().apply {
            put(MediaStore.MediaColumns.DISPLAY_NAME, "doc.txt")
            put(MediaStore.MediaColumns.MIME_TYPE, "text/plain")
            put(MediaStore.MediaColumns.RELATIVE_PATH, "Documents")
        }

        val uri = resolver.insert(MediaStore.Files.getContentUri("external"), contentValues)

        uri?.let {
            resolver.openOutputStream(it).use {
                // Write file
                it?.write("line1".toByteArray(Charset.defaultCharset()))
                it?.write("line2".toByteArray(Charset.defaultCharset()))
                it?.close()
            }

        }

我第一次执行此代码时，将按预期方式创建文件'doc.txt'.

The first time I execute this code, the file 'doc.txt' is created like expected.

但是，如果我再次执行相同的代码，它将为我创建一个新文件'doc(1).txt'，而不是编辑我已经创建的文件.

But if I execute the same code again, it create me a new file 'doc (1).txt' instead of editing the file I already created.

当原始的'doc.txt'文件已经存在时，该如何修改?

How can I modify the original 'doc.txt' file when it already exist ?

据我了解，因为创建了该文件，所以我应该能够在该文件上写东西.

In my understanding, I should be able to write on this file because I created it.

推荐答案

但是，如果我再次执行相同的代码，它将为我创建一个新文件'doc(1).txt'，而不是编辑我已经创建的文件.

But if I execute the same code again, it create me a new file 'doc (1).txt' instead of editing the file I already created.

您的代码有两件事:

• 将新条目插入MediaStore
• 为insert()返回的Uri打开OutputStream并将内容写入该流

• Inserts a new entry into the MediaStore
• Opens an OutputStream for the Uri returned by insert() and writes content to that stream

如果您不想添加新条目，请不要插入新条目.

If you do not not want a new entry, do not insert one.

当原始的"doc.txt"文件已经存在时，如何修改?

How can I modify the original 'doc.txt' file when it already exist ?

为最初获得的Uri打开一个OutputStream，然后将内容写入该流.

Open an OutputStream for the Uri that you were given originally, and write content to that stream.

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