android - ACTION_VIEW intent for a file with unknown MimeType

Question

My app has a feature that browse files on your phone and SD card and open them using other apps. I want a solution where I don't have to specify the MimeType and can work with any type of file.

Here is my code:

Intent myIntent = new Intent(Intent.ACTION_VIEW);
myIntent.setData(Uri.fromFile(item));
startActivity(myIntent);

However, I'm getting the following error:

android.content.ActivityNotFoundException: No Activity found to handle Intent { act=android.intent.action.PICK dat=file:///sdcard/dropbox/test.pdf }

Answer 1

This should detect the mimetype and open with default:

MimeTypeMap myMime = MimeTypeMap.getSingleton();
Intent newIntent = new Intent(Intent.ACTION_VIEW);
String mimeType = myMime.getMimeTypeFromExtension(fileExt(getFile()).substring(1));
newIntent.setDataAndType(Uri.fromFile(getFile()),mimeType);
newIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
try {
    context.startActivity(newIntent);
} catch (ActivityNotFoundException e) {
    Toast.makeText(context, "No handler for this type of file.", Toast.LENGTH_LONG).show();
}

Using this function:

private String fileExt(String url) {
    if (url.indexOf("?") > -1) {
        url = url.substring(0, url.indexOf("?"));
    }
    if (url.lastIndexOf(".") == -1) {
        return null;
    } else {
        String ext = url.substring(url.lastIndexOf(".") + 1);
        if (ext.indexOf("%") > -1) {
            ext = ext.substring(0, ext.indexOf("%"));
        }
        if (ext.indexOf("/") > -1) {
            ext = ext.substring(0, ext.indexOf("/"));
        }
        return ext.toLowerCase();

    }
}