java - The switch statent and return values - How to use a switch to determin JPanel drawn -


i have program has different jpanels written in different classes. print particular jpanel depending on button clicked user.

when program launched, has 3 buttons: "animals jbutton", "plants jbutton" , "refresh jbutton" in jframe "frame"; no jpanel.

if, example, user clicks on "animals jbutton", jpanel animals gets printed on jframe.

the "animalsjpanel" , "plantsjpanel" written in different classes. class, "pagereturner", has method determines gets printed via switch.

public class redirect {      string pageanimals = "pageanimals";     string pageplants = "pageplants";      string value;      public string pageredirect (string pageid) {         switch (pageid) {             case pageanimals:                 value = (animalsjpanel animalsjpanel = new animalsjpanel());             break;             case pageplants:                 value = (plantsjpanel plantsjpanel = new plantsjpanel());                 break;             case 2:                 value = null;                 break;         }         return null;      }  }

i "constant string expression required" , "incopatible types" errors in netbeans. might problem switch statement, , there better way go this, i.e, determining page print. i'd code , not use cardlayout. i'm new java , trying learn how objects classes.

is switch statement done. i'm teaching myself programming, , have no 1 consult. appreaciation in advance advice

declare variable final used in switch case.

   final string pageanimals = "pageanimals";    final string pageplants = "pageplants";

since case labels should compile time constants in switch.


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