Android将PDF文件共享到SDK 27下的另一个应用程序

<provider
    android:name="androidx.core.content.FileProvider"
    android:authorities="com.example.myapp.fileprovider"
    android:exported="false"
    android:grantUriPermissions="true">
    <meta-data
        android:name="android.support.FILE_PROVIDER_PATHS"
        android:resource="@xml/file_paths" />
</provider>

<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="external_files" path="." />
</paths>

File pdfFile = new File(getFilesDir(), "example.pdf");
Uri pdfUri = FileProvider.getUriForFile(this, "com.example.myapp.fileprovider", pdfFile);

Intent shareIntent = new Intent(Intent.ACTION_SEND);
shareIntent.setType("application/pdf");
shareIntent.putExtra(Intent.EXTRA_STREAM, pdfUri);
shareIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);

startActivity(Intent.createChooser(shareIntent, "Share PDF"));