qt quick - Bounds of Flickable.contentY in QML -

what correct way of asking bounds of flickable.contenty? need scrollbar.

experimentally have discovered

offsety <= contenty <= offsety + contentheight - height 

where offsety can calculated as

var offsety = contenty-math.round(visiblearea.yposition*contentheight) 

offsety 0 @ start of application , seems constant unless flickable resized.

this formula works in general, there should dedicated function it.

i did scrollbar without offset :

// scrollbar.qml import qtquick 2.0  rectangle {     id: scrollbar;     color: "#3c3c3c";     visible: (flicker.visiblearea.heightratio < 1.0);     property flickable flicker : null;     width: 20;     anchors {         top: flicker.top;         right: flicker.right;         bottom: flicker.bottom;     }      rectangle {         id: handle;         height: (scrollbar.height * flicker.visiblearea.heightratio);         color: "#5e5e5e";         border {             width: 1;             color: "white";         }         anchors {             left: parent.left;             right: parent.right;         }          binding { // calculate handle's x/y position based on content position of flickable             target: handle;             property: "y";             value: (flicker.visiblearea.yposition * scrollbar.height);             when: (!dragger.drag.active);         }         binding { // calculate flickable content position based on handle x/y position             target: flicker;             property: "contenty";             value: (handle.y / scrollbar.height * flicker.contentheight);             when: (dragger.drag.active);         }         mousearea {             id: dragger;             anchors.fill: parent;             drag {                 target: handle;                 minimumx: handle.x;                 maximumx: handle.x;                 minimumy: 0;                 maximumy: (scrollbar.height - handle.height);                 axis: drag.yaxis;             }         }     } } 

just use :

flickable {     id: myflick; } scrollbar {      flicker: myflick; } 

it can moved mouse, , moves automatically when flickable scrolled.