[QGIS-Developer] QgsMapLayerComboBox constantly firing events when hovering over it

[Richard Duivenvoorde]

Building a plugin in which I used a QgsMapLayerComboBox and running it in a QGIS debug build with full debug output, I see the following when I just hover/move over de combobox with my mouse (and having a project with an OSM layer):

src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [8ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [8ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [8ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [186ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [29ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [8ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [8ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [8ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [5ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [8ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [8ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [7ms] returning name 'OpenStreetMap'
src/core/qgsmaplayer.cpp:186 : (name) [178ms] returning name 'OpenStreetMap'

To me it looks like there is some hover-event over every pixel or so?

Is this an issue? Looking into the code there is some drag and drop code, so maybe it is for that?

Wondering if this is OK, or if this is a potential performance issue?

Regards,

Richard Duivenvoorde