Add helper method to open the play-store (and install nc files app)

package de.luhmer.owncloud.accountimporter.helper;

import android.content.Context;

import android.content.Intent;

import android.net.Uri;

/**

 *  Nextcloud SingleSignOn

 *

 *  @author David Luhmer

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

public class FilesAppNotInstalledHelper {

    public static void RequestInstallNextcloudFilesApp(Context context) {

        // DAVdroid not installed

        Intent installIntent = new Intent(Intent.ACTION_VIEW, Uri.parse("market://details?id=com.nextcloud.client"));

        // launch market(s)

        if (installIntent.resolveActivity(context.getPackageManager()) != null) {

            context.startActivity(installIntent);

        } else {

            // no f-droid market app or Play store installed --> launch browser for f-droid url

            Intent downloadIntent = new Intent(Intent.ACTION_VIEW, Uri.parse("https://f-droid.org/repository/browse/?fdid=com.nextcloud.client"));

            context.startActivity(downloadIntent);

        }

    }

}