code: public final void setDialogIcon(@DrawableRes final int resourceId) {
          this.dialogIcon = AppCompatResources.getDrawable(getContext(), resourceId);
          this.dialogIconBitmap = null;
          this.dialogIconId = resourceId;
      }
docs: Sets the icon of the preference's dialog.
  
  @param resourceId
  The resource id of the icon, which should be set, as an {@link Integer} value. The
  resource id must correspond to a valid drawable resource