java - ComboBox cannot be cast to TextField? -


i have arraylist of javafx.scene.control.control (arraylist) 2 different underclasses of control(combobox, textfield).

so want update list new input(example) in both of them.

but when try it, eclipse makes error this:

exception in thread "javafx application thread" java.lang.classcastexception: javafx.scene.control.combobox cannot cast javafx.scene.control.textfield     @ application.documentbuildup.aktualisiereliste(documentbuildup.java:34)     @ application.mainstage$2.handle(mainstage.java:99)     @ application.mainstage$2.handle(mainstage.java:1)     @ com.sun.javafx.event.compositeeventhandler.dispatchbubblingevent(unknown source)     @ com.sun.javafx.event.eventhandlermanager.dispatchbubblingevent(unknown source)     @ com.sun.javafx.event.eventhandlermanager.dispatchbubblingevent(unknown source)     @ com.sun.javafx.event.compositeeventdispatcher.dispatchbubblingevent(unknown source)     @ com.sun.javafx.event.basiceventdispatcher.dispatchevent(unknown source)     @ com.sun.javafx.event.eventdispatchchainimpl.dispatchevent(unknown source)     @ com.sun.javafx.event.basiceventdispatcher.dispatchevent(unknown source)     @ com.sun.javafx.event.eventdispatchchainimpl.dispatchevent(unknown source)     @ com.sun.javafx.event.basiceventdispatcher.dispatchevent(unknown source)     @ com.sun.javafx.event.eventdispatchchainimpl.dispatchevent(unknown source)     @ com.sun.javafx.event.basiceventdispatcher.dispatchevent(unknown source)     @ com.sun.javafx.event.eventdispatchchainimpl.dispatchevent(unknown source)     @ com.sun.javafx.event.basiceventdispatcher.dispatchevent(unknown source)     @ com.sun.javafx.event.eventdispatchchainimpl.dispatchevent(unknown source)     @ com.sun.javafx.event.eventutil.fireeventimpl(unknown source)     @ com.sun.javafx.event.eventutil.fireevent(unknown source)     @ javafx.event.event.fireevent(unknown source)     @ javafx.scene.node.fireevent(unknown source)     @ javafx.scene.control.button.fire(unknown source)     @ com.sun.javafx.scene.control.behavior.buttonbehavior.mousereleased(unknown source)     @ com.sun.javafx.scene.control.skin.behaviorskinbase$1.handle(unknown source)     @ com.sun.javafx.scene.control.skin.behaviorskinbase$1.handle(unknown source)     @ com.sun.javafx.event.compositeeventhandler$normaleventhandlerrecord.handlebubblingevent(unknown source)     @ com.sun.javafx.event.compositeeventhandler.dispatchbubblingevent(unknown source)     @ com.sun.javafx.event.eventhandlermanager.dispatchbubblingevent(unknown source)     @ com.sun.javafx.event.eventhandlermanager.dispatchbubblingevent(unknown source)     @ com.sun.javafx.event.compositeeventdispatcher.dispatchbubblingevent(unknown source)     @ com.sun.javafx.event.basiceventdispatcher.dispatchevent(unknown source)     @ com.sun.javafx.event.eventdispatchchainimpl.dispatchevent(unknown source)     @ com.sun.javafx.event.basiceventdispatcher.dispatchevent(unknown source)     @ com.sun.javafx.event.eventdispatchchainimpl.dispatchevent(unknown source)     @ com.sun.javafx.event.basiceventdispatcher.dispatchevent(unknown source)     @ com.sun.javafx.event.eventdispatchchainimpl.dispatchevent(unknown source)     @ com.sun.javafx.event.basiceventdispatcher.dispatchevent(unknown source)     @ com.sun.javafx.event.eventdispatchchainimpl.dispatchevent(unknown source)     @ com.sun.javafx.event.basiceventdispatcher.dispatchevent(unknown source)     @ com.sun.javafx.event.eventdispatchchainimpl.dispatchevent(unknown source)     @ com.sun.javafx.event.eventutil.fireeventimpl(unknown source)     @ com.sun.javafx.event.eventutil.fireevent(unknown source)     @ javafx.event.event.fireevent(unknown source)     @ javafx.scene.scene$mousehandler.process(unknown source)     @ javafx.scene.scene$mousehandler.access$1500(unknown source)     @ javafx.scene.scene.impl_processmouseevent(unknown source)     @ javafx.scene.scene$scenepeerlistener.mouseevent(unknown source)     @ com.sun.javafx.tk.quantum.glassvieweventhandler$mouseeventnotification.run(unknown source)     @ com.sun.javafx.tk.quantum.glassvieweventhandler$mouseeventnotification.run(unknown source)     @ java.security.accesscontroller.doprivileged(native method)     @ com.sun.javafx.tk.quantum.glassvieweventhandler.lambda$handlemouseevent$354(unknown source)     @ com.sun.javafx.tk.quantum.quantumtoolkit.runwithoutrenderlock(unknown source)     @ com.sun.javafx.tk.quantum.glassvieweventhandler.handlemouseevent(unknown source)     @ com.sun.glass.ui.view.handlemouseevent(unknown source)     @ com.sun.glass.ui.view.notifymouse(unknown source)     @ com.sun.glass.ui.win.winapplication._runloop(native method)     @ com.sun.glass.ui.win.winapplication.lambda$null$148(unknown source)     @ java.lang.thread.run(unknown source) 

i hope can help.

here code. class dokumentbuilup has method updatelist. named "aktualisiereliste". :))

class mainstage:

public class mainstage extends application {      /**      * globale variablen      */      private int abstandszaehler = 0;      private scrollpane rahmen = new scrollpane();      private xmlactions xa = new xmlactions();      private pane partpane = new pane();      private group huelle = new group();      private int id = 0;      private list<control> entries = new arraylist<control>();      private documentbuildup dbu = new documentbuildup(entries);         /**      * main class javafx application extends javafx.application.application class.       * start() method main entry point javafx applications.      */     public static void main(string[] args) {         launch(args);     }       @override     public void start(stage primarystage) {         //policy bezüglich scrollingverhalten         rahmen.sethbarpolicy(scrollbarpolicy.always);         rahmen.setvbarpolicy(scrollbarpolicy.always);          //fenster konfigurieren und anzeigen         primarystage.settitle("xml-zeilenersteller");         primarystage.setresizable(false);           //erzeugt notwendige elemente im gui          erzeugeeinzelneelemente();          partpane.setstyle("-fx-background-color: lightsteelblue");         huelle.getchildren().addall(partpane);         rahmen.setcontent(huelle);         scene mainscene = new scene(rahmen, 900, 590);         primarystage.setscene(mainscene);         primarystage.show();     }            /**      * hauptelemente für die root      */     public void erzeugeeinzelneelemente(){         //buttons         button newxmlline = new button();         newxmlline.settext("einfügen neuer xml-zeile");         newxmlline.setlayoutx(735);         newxmlline.setlayouty(80);         newxmlline.setonaction(new eventhandler<actionevent>() {             @override             public void handle(actionevent event) {                 seteverythinginaline();             }         });          button newxmldocument = new button();         newxmldocument.settext("erstelle xml-dokument");         newxmldocument.setlayoutx(735);         newxmldocument.setlayouty(550);         newxmldocument.setonaction(new eventhandler<actionevent>() {             @override             public void handle(actionevent event) {                   dbu.aktualisiereliste(entries);                  system.out.println("test2");             }         });          //Überschrift         text header = new text(105, 50, "xml lines creator");         header.setfont(new font(30)); header.setstyle("-fx-underline: true;");          /**          * hinzufügen zur gui          */         partpane.getchildren().addall(newxmldocument,newxmlline,header);     }           /**      * methode zur erstellungen der zeilen comboboxen, textfelder      */     @suppresswarnings({ "rawtypes", "unchecked" })     public void seteverythinginaline(){         //comboboxen         combobox cb = new combobox(xa.getlist());            partpane.getchildren().add(cb);         cb.setlayoutx(80);         cb.setlayouty(80 + abstandszaehler);         entries.add(cb);         id++; //        cb.setid(integer.tostring(id));          //textfield         textfield tfid= new textfield ("id");         partpane.getchildren().add(tfid);         tfid.setlayoutx(185);         tfid.setlayouty(80 + abstandszaehler);         entries.add(tfid);            textfield tfname= new textfield ("name");         partpane.getchildren().add(tfname);         tfname.setlayoutx(340);         tfname.setlayouty(80 + abstandszaehler);         entries.add(tfname);           textfield tfwert= new textfield ("wert");         partpane.getchildren().add(tfwert);         tfwert.setlayoutx(495);         tfwert.setlayouty(80 + abstandszaehler);         entries.add(tfwert);           system.out.println(integer.tostring(id));          //zaehler für den abstand         abstandszaehler = abstandszaehler + 30;          system.out.println(entries);     } } 

class documentbuilup:

public class documentbuildup{      @suppresswarnings("unused")     private list<control> list;      public documentbuildup(list<control> list){         this.list = list;     }      public list<string> aktualisiereliste(list<control> list ){          list<string> stringentries = new arraylist<string>();          for(int i=0; i<=list.size()-1; i++){              //brauche die zahl beim anklicken der zeile listener?                if(i%3 == 1){                 combobox cb = (combobox) list.get(i);                 stringentries.add((string) cb.getvalue());              }              if(i%3 == 2 || i%3 == 0){                 textfield tf = (textfield) list.get(i);                 stringentries.add(tf.gettext());             }         }         system.out.println(stringentries);          return stringentries;     } } 

edit: try 2 seperated lists. 1 combobox , 1 textfield.

edit 2: working 2 arraylists!! :))

if compare how content of entries list added , how use in aktualisiereliste should able see problem:

public void seteverythinginaline(){     ...     entries.add(somecombobox);     ...     entries.add(sometextfield);     ...     entries.add(sometextfield2);     ...     entries.add(sometextfield3); } 

this means there subsequence of 3 textfields. first element combobox

public list<string> aktualisiereliste(list<control> list ){     ...     for(int i=0; i<=list.size()-1; i++){         if(i%3 == 1){             combobox cb = (combobox) list.get(i);             ...         }          if(i%3 == 2 || i%3 == 0){             textfield tf = (textfield) list.get(i);             ...         }     }     ... } 

here assume first element (index 0) textfield (0 % 3 = 0), isn't case. subsequence of 3 textfields produce error, since 3 consecutive indices produce 3 different values modulo 3:

 1 % 3 = 1  2 % 3 = 2  3 % 3 = 0 

which cause classcastexception.

i'd consider adding elements list , retrieving them way bad practice, since can't change order of elements (well can, strict restrictions) without breaking other aktualisiereliste. better approach use instanceof check element type:

    for(control c : list) {         if(c instanceof combobox){             combobox cb = (combobox) c;             ...         } else {             textfield tf = (textfield) c;             ...         }     } 

however keep list date registering change listeners controls, i'd prefer:

public class listmodifyingchangelistener implements changelistener<string> {     private final int index;     private final list<string> list;      public listmodifyingchangelistener(int index, list<string> list) {         this.index = index;         this.list = list;     }      @override     public void changed(observablevalue<? extends string> observable, string oldvalue, string newvalue) {         list.set(index, newvalue);     }  } 
    list<string> liste; // declared field      combobox<string> cb = ...     ...      // create fixed sized list initial values     liste = arrays.aslist(cb.getvalue(), tfid.gettext(), tfname.gettext(), tfwert.gettext());      // register listeners modify element of liste on change     cb.valueproperty().addlistener(new listmodifyingchangelistener(0, liste));     tfid.textproperty().addlistener(new listmodifyingchangelistener(1, liste));     tfname.textproperty().addlistener(new listmodifyingchangelistener(2, liste));     tfwert.textproperty().addlistener(new listmodifyingchangelistener(3, liste)); 

this makes sure liste contains recent values , prevents unnecessary recreation of lists. no need pass list of controls method , distinguish control types...


Comments

Popular posts from this blog

get url and add instance to a model with prefilled foreign key :django admin -

css - Make div keyboard-scrollable in jQuery Mobile? -

ruby on rails - Seeing duplicate requests handled with Unicorn -