layout - JavaFX Resizing VBOX dynamically -

i having problems vbox, looked other questions me, sadly nothing worked. have vbox bunch of slider , buttons, , happens can rezise pretty want. can make small buttons inside disappear, or can make big cover other parts of program. tried vbox.setmaxsize , vbox.setminxsize, nothing happed. should buttons , sliders inside it? though since buttons , sliders vbox childrem, changes made on vbox them also. post controller class followed fxml file, fell free tell me if other classes needed. thank much.

controller

package fotofinish;  import java.io.file; import java.net.url; import java.util.resourcebundle; import java.util.logging.level; import java.util.logging.logger; import javafx.application.platform; import javafx.beans.value.observablevalue; import javafx.event.actionevent; import javafx.fxml.fxml; import javafx.fxml.initializable; import javafx.scene.control.colorpicker; import javafx.scene.control.radiobutton; import javafx.scene.control.scrollpane; import javafx.scene.control.slider; import javafx.scene.control.togglegroup; import javafx.scene.image.imageview; import javafx.scene.layout.priority; import javafx.scene.layout.vbox; import javafx.stage.filechooser; import javafx.stage.filechooser.extensionfilter; import javafx.stage.stage;  //todo: find better way have image refreshed public class fxmldocumentcontroller implements initializable {      private static final logger logger = logger.getlogger(fotofinish.fxmldocumentcontroller.class.getname());      stage stage;     private fotofinishmodel model = new fotofinishmodel();     @fxml     private slider brightnessslider;     @fxml     private slider contrastslider;     @fxml     private togglegroup brushtyperadiogroup;     @fxml     private radiobutton brushtypecircleradiobutton;     @fxml     private radiobutton brushtypespraypaintradiobutton;     @fxml     private radiobutton brushtypesquareradiobutton;     @fxml     private colorpicker brushcolorpicker;     @fxml     private numberfieldfx brushsizenumberfield;     @fxml     private imageview imageviewer;     @fxml     private scrollpane imagescrollpane;     @fxml     private vbox vbox;       @override     public void initialize(url url, resourcebundle rb) {         //todo: block increment?         this.brightnessslider.valueproperty().addlistener((observablevalue<? extends number> observable, number oldvalue, number newvalue) -> {             if(model.changebrightness(newvalue.doublevalue())) {                 this.refreshimageviewer();             }         });          //todo: convert dragged call         this.contrastslider.valueproperty().addlistener((observablevalue<? extends number> observable, number oldvalue, number newvalue) -> {             if (model.changecontrast(newvalue.doublevalue())) {                 this.refreshimageviewer();             }         });     }      @fxml     private void filtergrayscale(actionevent ignored) {         model.applygrayscalefilter();         this.refreshimageviewer();         this.resetsliders();     }      @fxml     private void filtersepia(actionevent ignored) {         model.applysepiafilter();         this.refreshimageviewer();         this.resetsliders();     }      @fxml     private void filterinstant(actionevent ignored) {         model.applyinstantfilter();         this.refreshimageviewer();         this.resetsliders();     }      @fxml     private void filtercustom(actionevent ignored) {         //todo: code create custom filter popup , arguments custom filter         logger.log(level.info, "todo: custom filter popup launched");         model.applycustomfilter();         this.refreshimageviewer();         this.resetsliders();     }      @fxml     private void filternone(actionevent ignored) {         model.resetimagetooriginal();         this.refreshimageviewer();         this.resetsliders();     }      @fxml     private void brushtypecircle(actionevent ignored) {         model.setbrushtypecircle();     }      @fxml     private void brushtypesquare(actionevent ignored) {         model.setbrushtypesquare();     }      @fxml     private void brushtypespraypaint(actionevent ignored) {         model.setbrushtypespraypaint();     }      @fxml     private void helpdoc(actionevent ignored) {         logger.log(level.info, "todo: document launched");     }      @fxml     private void aboutdialog(actionevent ignored) {         logger.log(level.info, "todo: dialog created");     }      @fxml     private void brushcolor(actionevent ignored) {         model.changebrushcolor(this.brushcolorpicker.getvalue());     }      @fxml     private void brushsize(actionevent ignored) {         model.changebrushsize(integer.parseint(this.brushsizenumberfield.gettext()));     }      //todo: make title setting more intelligent     @fxml     private void open(actionevent ignored) {         logger.log(level.info, "open file chooser launched");         filechooser filechooser = new filechooser();         filechooser.settitle("open image");         filechooser.getextensionfilters().add(new extensionfilter("image files", "*.png")); //todo: add other types         file selectedfile = filechooser.showopendialog(null); //todo: needs value in order block main window         if (selectedfile != null) {             logger.log(level.info, "file {0} choosen in open file chooser", selectedfile);             model.loadimage(selectedfile);             this.refreshimageviewer();             this.stage.settitle("foto finish - " + selectedfile);         } else {             logger.log(level.info, "no file selected in open file chooser");         }     }      @fxml     private void gallerybutterfly(actionevent ignored) {         model.loadgallerybutterflyimage();         this.refreshimageviewer();     }      @fxml     private void galleryteddybear(actionevent ignored) {         model.loadgalleryteddybearimage();         this.refreshimageviewer();     }      @fxml     private void galleryprincess(actionevent ignored) {         model.loadgalleryprincessimage();         this.refreshimageviewer();     }      @fxml     private void galleryfirefighter(actionevent ignored) {         model.loadgalleryfirefighterimage();         this.refreshimageviewer();     }      @fxml     private void save(actionevent ignored) {         model.saveimage();     }      @fxml     private void saveas(actionevent ignored) {         logger.log(level.info, "save file chooser launched");         filechooser filechooser = new filechooser();         filechooser.settitle("save image");         filechooser.getextensionfilters().add(new extensionfilter("image files", "*.png")); //todo: add other types         file selectedfile = filechooser.showsavedialog(null); //todo: needs value in order block main window         if (selectedfile != null) {             logger.log(level.info, "file {0} choosen in save file chooser", selectedfile);             model.saveimageas(selectedfile);         } else {             logger.log(level.info, "no file selected in save file chooser");         }     }      @fxml     private void quit(actionevent ignored) {         logger.log(level.info, "quitting");         platform.exit(); //todo: make detect unsaved changes     }      @fxml     private void newfile(actionevent ignored) {         logger.log(level.info, "todo: new file created");     }      private void refreshimageviewer() {         this.imageviewer.setimage(model.getimage());         logger.log(level.info, "image refreshed");     }      //todo: make connect better fxml default value     private void resetsliders() {         this.brightnessslider.setvalue(0);         this.contrastslider.setvalue(0);         logger.log(level.info, "brightness , contrast sliders reset");     }      public void setstage(stage stagefrommain) {         this.stage = stagefrommain;     } } 

fxml

<?xml version="1.0" encoding="utf-8"?>  <?import javafx.geometry.*?> <?import javafx.scene.input.*?> <?import javafx.scene.image.*?> <?import java.lang.*?> <?import java.util.*?> <?import javafx.scene.*?> <?import javafx.scene.control.*?> <?import javafx.scene.layout.*?>  <borderpane maxheight="-infinity" maxwidth="-infinity" minheight="500.0" minwidth="600.0" prefheight="700.0" prefwidth="1200.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="fotofinish.fxmldocumentcontroller">    <top>       <menubar prefheight="0.0" prefwidth="1034.0" borderpane.alignment="center">         <menus>           <menu mnemonicparsing="false" text="file">             <items>                   <menuitem fx:id="menubarfilenew" mnemonicparsing="false" onaction="#newfile" text="new">                      <accelerator>                         <keycodecombination alt="up" code="n" control="down" meta="up" shift="up" shortcut="up" />                      </accelerator>                   </menuitem>                   <separatormenuitem mnemonicparsing="false" />                   <menuitem fx:id="menubarfileopen" mnemonicparsing="false" onaction="#open" text="open">                      <accelerator>                         <keycodecombination alt="up" code="o" control="down" meta="up" shift="up" shortcut="up" />                      </accelerator>                   </menuitem>                   <menu mnemonicparsing="false" text="open gallery">                     <items>                       <menuitem fx:id="menubarfilegallerybutterfly" mnemonicparsing="false" onaction="#gallerybutterfly" text="butterfly" />                         <menuitem fx:id="menubarfilegalleryteddybear" mnemonicparsing="false" onaction="#galleryteddybear" text="teddy bear" />                         <menuitem fx:id="menubarfilegalleryprincess" mnemonicparsing="false" onaction="#galleryprincess" text="princess" />                         <menuitem fx:id="menubarfilegalleryfirefighter" mnemonicparsing="false" onaction="#galleryfirefighter" text="firefighter" />                     </items>                   </menu>                   <separatormenuitem mnemonicparsing="false" />                   <menuitem fx:id="menubarfilesave" mnemonicparsing="false" onaction="#save" text="save">                      <accelerator>                         <keycodecombination alt="up" code="s" control="down" meta="up" shift="up" shortcut="up" />                      </accelerator>                   </menuitem>                   <menuitem fx:id="menubarfilesaveas" mnemonicparsing="false" onaction="#saveas" text="save as">                      <accelerator>                         <keycodecombination alt="up" code="s" control="down" meta="up" shift="down" shortcut="up" />                      </accelerator>                   </menuitem>                   <separatormenuitem mnemonicparsing="false" />               <menuitem fx:id="menubarfilequit" mnemonicparsing="false" onaction="#quit" text="quit">                      <accelerator>                         <keycodecombination alt="up" code="c" control="down" meta="up" shift="up" shortcut="up" />                      </accelerator></menuitem>             </items>           </menu>           <menu mnemonicparsing="false" text="help">             <items>               <menuitem fx:id="menubarhelpfotofinishhelpmenuitem" mnemonicparsing="false" onaction="#helpdoc" text="foto finish help">                      <accelerator>                         <keycodecombination alt="up" code="f1" control="up" meta="up" shift="up" shortcut="up" />                      </accelerator></menuitem>                   <menuitem fx:id="menubarhelpaboutmenuitem" mnemonicparsing="false" onaction="#aboutdialog" text="about" />             </items>           </menu>         </menus>       </menubar>    </top>    <center>       <splitpane dividerpositions="0.14941569282136896" minheight="-infinity" minwidth="-infinity" prefheight="160.0" prefwidth="200.0" borderpane.alignment="center">         <items>           <anchorpane minheight="0.0" minwidth="0.0" prefheight="160.0" prefwidth="100.0">                <children>                   <vbox fx:id="vbox" alignment="top_center" layoutx="-11.0" layouty="25.0" maxheight="1.7976931348623157e308" maxwidth="1.7976931348623157e308" minwidth="100.0" prefheight="200.0" prefwidth="100.0" anchorpane.bottomanchor="10.0" anchorpane.leftanchor="10.0" anchorpane.rightanchor="10.0" anchorpane.topanchor="10.0">                      <children>                         <label fx:id="sliderlabel" alignment="top_left" text="sliders">                            <padding>                               <insets left="10.0" />                            </padding>                         </label>                         <gridpane alignment="center">                           <columnconstraints>                             <columnconstraints halignment="center" hgrow="sometimes" maxwidth="104.0" minwidth="10.0" prefwidth="84.0" />                           </columnconstraints>                           <rowconstraints>                             <rowconstraints minheight="10.0" prefheight="30.0" vgrow="sometimes" />                             <rowconstraints minheight="10.0" prefheight="30.0" vgrow="sometimes" />                             <rowconstraints minheight="10.0" prefheight="30.0" vgrow="sometimes" />                               <rowconstraints minheight="10.0" prefheight="30.0" vgrow="sometimes" />                               <rowconstraints minheight="10.0" prefheight="30.0" vgrow="sometimes" />                               <rowconstraints minheight="10.0" prefheight="30.0" vgrow="sometimes" />                           </rowconstraints>                            <children>                               <button fx:id="filtergrayscalebutton" contentdisplay="top" mnemonicparsing="false" onaction="#filtergrayscale" prefheight="25.0" prefwidth="84.0" text="grayscale" textalignment="center" gridpane.rowindex="1">                                  <opaqueinsets>                                     <insets top="50.0" />                                  </opaqueinsets>                               </button>                               <button fx:id="filtersepiabutton" mnemonicparsing="false" onaction="#filtersepia" prefheight="25.0" prefwidth="83.0" text="sepia" gridpane.rowindex="2" />                               <button fx:id="filterinstantbutton" mnemonicparsing="false" onaction="#filterinstant" prefheight="25.0" prefwidth="83.0" text="instant" gridpane.rowindex="3" />                               <button fx:id="filtercustombutton" mnemonicparsing="false" onaction="#filtercustom" prefheight="25.0" prefwidth="82.0" text="custom" gridpane.rowindex="4" />                               <button fx:id="filternonebutton" mnemonicparsing="false" onaction="#filternone" prefheight="25.0" prefwidth="82.0" text="none" gridpane.rowindex="5" />                            </children>                            <padding>                               <insets left="10.0" />                            </padding>                         </gridpane>                         <gridpane prefheight="271.0" prefwidth="176.0">                           <columnconstraints>                             <columnconstraints halignment="center" hgrow="sometimes" minwidth="10.0" prefwidth="100.0" />                           </columnconstraints>                           <rowconstraints>                             <rowconstraints maxheight="88.0" minheight="10.0" prefheight="35.0" vgrow="sometimes" />                             <rowconstraints maxheight="290.0" minheight="26.0" prefheight="59.0" vgrow="sometimes" />                               <rowconstraints maxheight="233.0" minheight="6.0" prefheight="40.0" />                               <rowconstraints maxheight="127.0" minheight="28.0" prefheight="56.0" />                               <rowconstraints maxheight="148.0" minheight="23.0" prefheight="34.0" />                               <rowconstraints maxheight="124.0" minheight="41.0" prefheight="51.0" />                           </rowconstraints>                            <children>                               <label fx:id="brightnesslabel" text="brightness" />                               <label fx:id="contrastlabel" text="contrast" gridpane.rowindex="2" />                               <slider fx:id="brightnessslider" max="1.0" min="-1.0" minortickcount="10" orientation="horizontal" showticklabels="true" showtickmarks="true" snaptoticks="true" gridpane.rowindex="1" />                               <slider fx:id="contrastslider" max="1.0" min="-1.0" minortickcount="10" orientation="horizontal" showticklabels="true" showtickmarks="true" snaptoticks="true" gridpane.rowindex="3" />                               <label text="saturation" gridpane.rowindex="4" />                               <slider max="1.0" min="-1.0" minortickcount="10" showticklabels="true" showtickmarks="true" snaptoticks="true" gridpane.rowindex="5" />                            </children>                            <padding>                               <insets left="10.0" right="10.0" />                            </padding>                         </gridpane>                         <label fx:id="drawinglabel" text="drawing" />                         <colorpicker fx:id="brushcolorpicker" onaction="#brushcolor" />                         <label fx:id="brushtypelabel" text="brush type" />                         <radiobutton fx:id="brushtypecircleradiobutton" mnemonicparsing="false" onaction="#brushtypecircle" selected="true" text="circle">                            <togglegroup>                               <togglegroup fx:id="brushtyperadiogroup" />                            </togglegroup>                         </radiobutton>                         <radiobutton fx:id="brushtypesquareradiobutton" mnemonicparsing="false" onaction="#brushtypesquare" text="square" togglegroup="$brushtyperadiogroup" />                         <radiobutton fx:id="brushtypespraypaintradiobutton" mnemonicparsing="false" onaction="#brushtypespraypaint" text="spraypaint" togglegroup="$brushtyperadiogroup" />                         <label fx:id="brushsizelabel" text="brush size" />                         <fotofinish.numberfieldfx fx:id="brushsizetextfield" onaction="#brushsize" text="10" />                         <label fx:id="filterslabel" text="filters" />                      </children>                   </vbox>                </children>             </anchorpane>           <anchorpane minheight="0.0" minwidth="0.0" prefheight="369.0" prefwidth="465.0">                <children>                   <scrollpane layoutx="145.0" layouty="111.0" anchorpane.bottomanchor="0.0" anchorpane.leftanchor="0.0" anchorpane.rightanchor="0.0" anchorpane.topanchor="0.0">                      <content>                         <imageview fx:id="imageviewer" fitheight="577.0" fitwidth="1010.0" pickonbounds="true" preserveratio="true" />                      </content>                   </scrollpane>                </children>             </anchorpane>         </items>       </splitpane>    </center> </borderpane>