Android Gmail 不通过 FileProvider 附加文​​件的意图 "Unable to attach file"

Question

将文件附加到 Gmail 时，我在附件中短暂地看到了该文件，然后 Toast 提示“无法附加文件”，然后它就消失了。它适用于 Drive、Discord 和其他应用程序。 该文件也保留在模拟器的附件中，但是当我发送它时，邮件发送时没有附件。我有一个简单的 .csv 文件并通过 FileProvider 附加它。

尝试写入内部存储，没有帮助。

val fileLocation = File(requireContext().getExternalFilesDir("data"), "data.csv")

            // Saving the file into device
            val streamOut =
                FileOutputStream(fileLocation)
            streamOut.write(myString.toByteArray())
            streamOut.close()

            // Exporting

            val contentUri = FileProvider.getUriForFile(
                requireContext(),
                "mypackage.fileprovider",
                fileLocation
            )

            val fileIntent = Intent(Intent.ACTION_SEND)
                .setType("text/csv")
                .putExtra(Intent.EXTRA_SUBJECT, "Data")
                .addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
                .putExtra(Intent.EXTRA_STREAM, contentUri)

            val chooser = Intent.createChooser(
                fileIntent,
                requireContext().resources.getText(R.string.send_to)
            )

            chooser.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)

            val resInfoList: List<ResolveInfo> = requireActivity().packageManager
                .queryIntentActivities(chooser, PackageManager.MATCH_DEFAULT_ONLY)

            for (resolveInfo in resInfoList) {
                val packageName = resolveInfo.activityInfo.packageName
                requireActivity().grantUriPermission(
                    packageName,
                    contentUri,
                    Intent.FLAG_GRANT_WRITE_URI_PERMISSION or Intent.FLAG_GRANT_READ_URI_PERMISSION
                )
            }

            requireActivity().startActivity(
                chooser
            )

provider_paths

<paths>
    <external-files-path
        name="data"
        path="." />
</paths>

清单

<provider
            android:name="androidx.core.content.FileProvider"
            android:authorities="mypackage.fileprovider"
            android:exported="false"
            android:grantUriPermissions="true">

            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/provider_paths" />
        </provider>

Answer 1

您可以尝试更新您的 file_paths.xml 以使用外部路径的特定路径并尝试它是否有效？

请参阅下面我的工作解决方案。它使用多个附件，但适用于 Gmail 应用程序：

java class

private void prepareEmail(File report, List<Expense> openExpenses) {
    Intent intent = new Intent(Intent.ACTION_SEND_MULTIPLE);
    intent.setType("message/rfc822");
    intent.putExtra(Intent.EXTRA_EMAIL, new String[]{preferences.getEmailReceiver()});
    intent.putExtra(Intent.EXTRA_SUBJECT, preferences.getEmailSubject());
    intent.putExtra(Intent.EXTRA_TEXT, preferences.getEmailBody());

    ArrayList<Uri> uris = new ArrayList<>();
    uris.add(FileProvider.getUriForFile(getApplicationContext(), "my.package", report));
    for (Expense expense : openExpenses) {
        if (expense.getType() == ExpenseType.EXPENSE.getValue()) {
            File file = new File(expense.getReceipt());
            uris.add(FileProvider.getUriForFile(getApplicationContext(), "my.package", file));
        }
    }
    intent.putParcelableArrayListExtra(Intent.EXTRA_STREAM, uris);
    startActivity(Intent.createChooser(intent, getResources().getString(R.string.report_report_send)));
}

file_paths.xml

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="my_images" path="Android/data/my.package/files/Pictures" />
    <external-path name="my_pdfs" path="Android/data/my.package/files/Documents" />
    <external-path name="my_reports" path="Android/data/my.package/files" />
    <files-path name="files" path="." />
</paths>

清单

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
...
<provider
    android:name="androidx.core.content.FileProvider"
    android:authorities="my.package"
    android:exported="false"
    android:grantUriPermissions="true">
    <meta-data
        android:name="android.support.FILE_PROVIDER_PATHS"
        android:resource="@xml/file_paths" />
</provider>

Answer 2

通过根据此模板更改file_paths.xml解决了问题：

<?xml version="1.0" encoding="utf-8"?>
<paths>
  <external-path
    name="external"
    path="." />
  <external-files-path
    name="external_files"
    path="." />
  <cache-path
    name="cache"
    path="." />
  <external-cache-path
    name="external_cache"
    path="." />
<files-path
    name="files"
    path="." />
</paths>