LineChart.bottom_axis custom labels not showing unless value is the same as the first or last data_point.

[NathanCummings]

Duplicate Check

• I have searched the opened issues and there are no duplicates

Describe the bug

I'm trying to use POSIX timestamps (from datetime.datime.timestamp) as values fro my x-axis, but when I do, my labels stop appearing correctly.

I have prepared a minimal example with 2 datasets, one that works and one that doesn't.

Code sample

Code

import flet as ft

data_points_1 = [
    ft.LineChartDataPoint(1, 1),
    ft.LineChartDataPoint(3, 1.5),
    ft.LineChartDataPoint(5, 1.4),
    ft.LineChartDataPoint(7, 3.4),
    ft.LineChartDataPoint(10, 2),
    ft.LineChartDataPoint(12, 2.2),
    ft.LineChartDataPoint(13, 1.8),
]
labels_1 = [
    ft.ChartAxisLabel(value=2, label=ft.Text("SEP")),
    ft.ChartAxisLabel(value=7, label=ft.Text("OCT")),
    ft.ChartAxisLabel(value=12, label=ft.Text("DEC")),
]

data_points_2 = [
    ft.LineChartDataPoint(1735430400, 1),
    ft.LineChartDataPoint(1735948800, 1.5),
    ft.LineChartDataPoint(1736467200, 1.4),
    ft.LineChartDataPoint(1736812800, 3.4),
    ft.LineChartDataPoint(1737676800, 2),
    ft.LineChartDataPoint(1738800000, 2.2),
    ft.LineChartDataPoint(1741996800, 1.8),
]
labels_2 = [
    ft.ChartAxisLabel(value=1735430400, label=ft.Text("SEP")),
    ft.ChartAxisLabel(value=1736812800, label=ft.Text("OCT")),
    ft.ChartAxisLabel(value=1738800000, label=ft.Text("NOV")),
    ft.ChartAxisLabel(value=1741996800, label=ft.Text("DEC")),
]


def main(page: ft.Page):
    chart_1 = ft.LineChart(
        data_series=[ft.LineChartData(data_points_1)],
        top_axis=ft.ChartAxis(title=ft.Text("Working"), show_labels=False),
        bottom_axis=ft.ChartAxis(labels=labels_1),
    )
    chart_2 = ft.LineChart(
        data_series=[ft.LineChartData(data_points_2)],
        top_axis=ft.ChartAxis(title=ft.Text("Not Working"), show_labels=False),
        bottom_axis=ft.ChartAxis(labels=labels_2),
    )
    page.add(chart_1, chart_2)


ft.app(main)

To reproduce

To reproduce, run the supplied code.

Expected behavior

All labels to show along the bottom

Screenshots / Videos

Captures

Operating System

macOS

Operating system details

Sequoia 15.3.2

Flet version

0.26.0

Regression

No, it isn't

Suggestions

No response

Logs

Logs

[Paste your logs here]

Additional details

No response

[NathanCummings]

UPDATE:
Tried it in desktop mode and I get one more label, so there is some spacing-related reason for this behaviour. I'll keep investigating, but I still propose this is a bug as the behaviour is different if for default labels.