在Android中阅读pdf文件

Question

I am building an app that has function reading pdf file use ACTION_VIEW . If device has multiple pdf reader app installed,then it will show app chooser dialog. So, And if there is only one pdf reader installed in device, it seems impossible to show chooser dialog.

So my question is, is it possible to show chooser dialog if there is only one pdf reader installed?

Answer 1

Yes, it's possible to force a chooser even when there is exactly one Activity that will respond. Here's some sample code demonstrating this:

// Your original intent
Intent intent = new Intent(Intent.ACTION_VIEW);

// Configure your original intent as per usual here...

// Build a chooser intent based on your original intent
String title = getResources().getString(R.string.chooser_title);
Intent chooser = Intent.createChooser(intent, title);

// Verify the intent will resolve to at least one activity
if (intent.resolveActivity(getPackageManager()) != null) {
    startActivity(chooser);
}

Answer 2

No, if particular format is supported by multiple Applications then you can notify the user to choose from them but if you already configure an app as your default for particular type then you can't get chooser for that. I think you want,a user to have your app as option in that chooser so you can follow this Google documentation.

For creating non-commercial pdf app you could use MuPDF.