Error in POM Attribute value must be constant

hi want to ask

i want to get element but the element its for calendar and the id related to number:
example element:
calendarCell1
calendarCell2

so here my code

public static final Random rand = new Random();
public static final Integer min =1;
public static final Integer max =28;
public static final Integer value = rand.nextInt((max-min)+1)+min;
public static final String number = Integer.toString(value);
public static final String calendar = “calendarCell”+number+;

@iOSFindBy (xpath = " //*[contains(text()='"+calendar+"']")
IOSElement randomCalendar;

but i getting error Attribute value must be constant in iosfindby line
any suggest to use

Sorry I am not sure if this is really related to Appium Studio, looks like its more related to Appium Client Library , Check in Appium open source forums to get more information.