Use AndroidX

app/src/main/java/com/hippo/util/AppHelper.java

@@ -22,11 +22,11 @@ import android.app.Service;
 import android.content.Context;
 import android.content.Intent;
 import android.net.Uri;
-import android.support.annotation.NonNull;
-import android.support.annotation.Nullable;
 import android.view.View;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.Toast;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import com.hippo.ehviewer.R;
 
 public class AppHelper {