If I binding the title of the PieChart, the chart is not shown

Aug 29, 2014 at 10:49 AM
I have this axml:
<chart:PieChart Grid.Row="0" Grid.Column="0" Margin="0,0,0,0" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"
            ChartTitle="Horas de funcionamiento"
            SelectedItem="{Binding Path=SelectedItem, Mode=TwoWay}" Grid.ColumnSpan="2" >
                    SeriesTitle="{Binding PieChartTitulo}"
                    ItemsSource="{Binding Path=PieChartDatos}"/>

            <chart:RadialGaugeChart Grid.Row="0" Grid.Column="2" ChartTitle="Gauge Chart" ChartSubTitle=""
                                    VerticalAlignment="Stretch" HorizontalAlignment="Stretch">
                    <chart:ChartSeries SeriesTitle="Errors" DisplayMember="Category" ValueMember="Number" ItemsSource="{Binding Path=OrigenDatosGaugeChart}"/>
And I have this code in my view model:
PieChartTitulo = "Horas rendimientos desde ";
                    PieChartDatos.Add(new Dato() { Category = "Horas Funcionamiento", Number = (float)decHorasFuncionamiento });
                    PieChartDatos.Add(new Dato() { Category = "Horas Fallos", Number = (float)decHorasFallos });
                    PieChartDatos.Add(new Dato() { Category = "Horas sin uso", Number = (float)decHorasSinUso });
The title is binding correctly, but the chart is not shown.

How can I show that chart when I binding the title? Because when I set the title in the axml then the chart is shown.