handleDropEvent.java

	private void handleDropEvent(View view, DragEvent dragEvent) {
		ClipData clipData = dragEvent.getClipData();
		ClipData.Item item = clipData.getItemAt(0);
		Uri uri = item.getUri();
		if (uri != null) {
			String mimeType = URLConnection.guessContentTypeFromName(new File(uri.getPath()).getName());
			if (mimeType == null) {
				Snackbar.make(mainLayout, "Can't open file. The file type is unknown.", Snackbar.LENGTH_LONG).show();
			} else if (mimeType.startsWith("image")) {
				handleImage(uri);
			} else {
				Intent newIntent = new Intent(Intent.ACTION_VIEW);
				Uri contentUri = FileProvider.getUriForFile(this, BuildConfig.APPLICATION_ID + ".provider", new File(uri.getPath()));

				newIntent.setDataAndType(contentUri, mimeType);
				newIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
				List<ResolveInfo> resInfoList = getPackageManager().queryIntentActivities(newIntent, PackageManager.MATCH_DEFAULT_ONLY);
				for (ResolveInfo resolveInfo : resInfoList) {
					String packageName = resolveInfo.activityInfo.packageName;
					grantUriPermission(packageName, contentUri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
				}
				try {
					startActivity(newIntent);
				} catch (ActivityNotFoundException e) {
					Snackbar.make(mainLayout, "Sorry, I found no handler for this type of file.", Snackbar.LENGTH_SHORT).show();
				} catch (FileUriExposedException ex) {
					Snackbar.make(mainLayout, "FileUriExposedException", Snackbar.LENGTH_SHORT).show();
				}
			}
		} else if (item.getText() != null) {
			handleText(item.getText());
		} else {
			Log.e(TAG, "Unknown content: " + clipData);
		}
	}