ChartView keyboard events

[Bob64]

Hi,

I want to implement zooming/scrolling functionality on my use of ChartView and would like to provide the option of keyboard control. How to I detect a keyboard event on a ChartView?

I tried the probably naive approach of adding a Keys.onPressed handler to the ChartView but it does not get triggered. Unlike an Item, ChartView has no focus property, so I tried overlaying a transparent rectangle on the ChartView, setting focus: true on it and moving the keyboard event handler to the rectangle instead, but still no luck. Frustratingly the documentation for ChartView.scrollDown (for example) says "This is a convenience method suitable for key navigation, for example", which suggests that it should be possible.

Thanks in advance for any tips.

[6thC]

I use separate input controls like RangeSlider QML Type for my axis config's.

I also have a wrapper MouseArea that I use for Key inputs to interact with that, not my chart.
I manually give and take focus according to the mouse, so keys don't interact after you've left the chart (MouseArea ) region.:

MouseArea {
               id: itemMouseArea   ;
               anchors.fill: parent;
               propagateComposedEvents: true
               hoverEnabled: true  ;
               onEntered: {
                   forceActiveFocus()
               }
               onExited: {
                   if (configVisible === false) {
                       itemMouseArea.focus = false;
                   }
               }
               Keys.onPressed: {
                   if (event.key === Qt.Key_Left) {
                       row.updateShared(++slider.value);
                   }
                   if (event.key === Qt.Key_Right) {
                       if ( slider.value > 1){
                           row.updateShared(--slider.value);
                       }
                   }
                   event.accepted = true;
               }
           }

[6thC]

I use separate input controls like RangeSlider QML Type for my axis config's.

I also have a wrapper MouseArea that I use for Key inputs to interact with that, not my chart.
I manually give and take focus according to the mouse, so keys don't interact after you've left the chart (MouseArea ) region.:

MouseArea {
               id: itemMouseArea   ;
               anchors.fill: parent;
               propagateComposedEvents: true
               hoverEnabled: true  ;
               onEntered: {
                   forceActiveFocus()
               }
               onExited: {
                   if (configVisible === false) {
                       itemMouseArea.focus = false;
                   }
               }
               Keys.onPressed: {
                   if (event.key === Qt.Key_Left) {
                       row.updateShared(++slider.value);
                   }
                   if (event.key === Qt.Key_Right) {
                       if ( slider.value > 1){
                           row.updateShared(--slider.value);
                       }
                   }
                   event.accepted = true;
               }
           }

[Bob64]

@6thC Thank you!

I already had a MouseArea on the plot area of my ChartView but I hadn't thought to try to handle key events there. I think the idea of using the mouse enter and exit handlers to manually manage the focus - and in particular the forceActiveFocus call - were what I was missing and what I needed.