With the new fill mode the legend will only start displaying values once the chart is full. Probably because the HistoryProxySource shifts the indices back and the legend always reads from 0.
Git commit 87a80981be218236928e4c7c3bde7e8fe8f41f89 by Arjen Hiemstra. Committed on 03/02/2021 at 15:16. Pushed by ahiemstra into branch 'master'. Add a "first" method to ChartDataSource and use it in Legend This allows us to get the first valid item from a source. This is helpful when a source treats its items differently and a request for item 0 ends up not being a valid item, such as a HistoryProxySource with FillFromEnd fillMode. M +7 -0 src/datasource/ChartDataSource.cpp M +2 -0 src/datasource/ChartDataSource.h M +8 -0 src/datasource/HistoryProxySource.cpp M +2 -0 src/datasource/HistoryProxySource.h M +1 -1 src/decorations/LegendModel.cpp https://invent.kde.org/frameworks/kquickcharts/commit/87a80981be218236928e4c7c3bde7e8fe8f41f89