PDF viewer permission issue in android 11

Question

I am opening pdf file using an external pdf viewer application. But in android 11 shows eacces permission denied issue. All permissions already declared in my manifest file.

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
        <uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE"/>
        <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
        

Also declared this :

android:requestLegacyExternalStorage="true"

Creating and writing the content with below code :

byte [] decodedContent = Base64.decode(base64.getBytes(), Base64.DEFAULT);

                try {

                    File pdfDirPath = new File(getApplicationContext().getExternalFilesDir(null).getAbsolutePath(), "pdfs");
                    File file5 = new File(pdfDirPath, globalData.getVin()+".pdf");

                    if (!file5.exists()) {

                        file5.getParentFile().mkdirs();
                    }

                    outputStream = new FileOutputStream(file5);
                    outputStream.write(Base64.decode(base64, Base64.NO_WRAP));
                    outputStream.close();
               

And open above file like this :

    Uri   path = FileProvider.getUriForFile(getApplicationContext(), getApplicationContext().getPackageName() + ".helper.ProviderClass", file5);
  intent = new Intent(Intent.ACTION_VIEW);
            intent.setDataAndType(path, "application/pdf");
            intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
            intent.addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
            intent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);

Please help me with this.

Answer 1

Two points.

1. android:requestLegacyExternalStorage="true" is ignored on Android 11. This version of Android enforces scoped storage regardless of this flag in your Manifest, so you can safely take it out because it has no effect on your device.
2. Because scoped storage is enforced, apps are not allowed to access other apps' private storage locations. In your case you are saving your file in getApplicationContext().getExternalFilesDir(null).getAbsolutePath() which is your app's private location. Scoped storage rules on Android 11 will prohibit your external PDF viewer app to open any file in your app's location. On Android 11 if you want another app to open a doc that your app created you have at least two choices and may be more.

a) A complicated one. Use FileProvider https://developer.android.com/reference/androidx/core/content/FileProvider

b) This one is much simpler one. Since your intention is to share this file with another app, instead of writing into your app's specific directory you should use MediaStore API and write it into the MediaStore.Downloads.EXTERNAL_CONTENT_URI. There are many good examples on the net how to do it, for example How to save pdf in scoped storage? Your PDF Viewer should have no problem accessing it from there.