#1,029 – Simple ProgressBar Example

Here’s an example of how we could use a ProgressBar in an application to show # records processed.

    <StackPanel>
        <ProgressBar Value="{Binding NumRecsLoaded}" Maximum="{Binding TotalNumRecs}"
                     Height="15" Margin="15,15,15,0"/>
        <Label Content="{Binding RecsLoadedMessage}"
               Margin="10,0"/>
        <Button Margin="15" Padding="15,3" HorizontalAlignment="Center"
            Content="Start" Click="Button_Click"/>
    </StackPanel>

In code, we declare properties for total number of records and number already loaded. When the user clicks on the Button, we set up a timer that increments the # records loaded each time that it ticks (twice a second).  (Note–to use the DispatcherTimer, you need to use namespace System.Windows.Threading).

    public partial class MainWindow : Window, INotifyPropertyChanged
    {
        private int numRecsLoaded = 0;
        public int NumRecsLoaded
        {
            get { return numRecsLoaded; }
            protected set
            {
                numRecsLoaded = value;
                RaisePropertyChanged("NumRecsLoaded");
                RaisePropertyChanged("RecsLoadedMessage");
            }
        }

        private int totalNumRecs = 12;
        public int TotalNumRecs
        {
            get { return totalNumRecs; }
            protected set
            {
                totalNumRecs = value;
                RaisePropertyChanged("TotalNumRecs");
            }
        }

        public string RecsLoadedMessage
        {
            get { return string.Format("Loaded {0} records...", numRecsLoaded);  }
        }

        public MainWindow()
        {
            InitializeComponent();
            this.DataContext = this;

        }

        // INotifyPropertyChanged
        public event PropertyChangedEventHandler PropertyChanged = delegate { };

        private void RaisePropertyChanged(string propName)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(propName));
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            DispatcherTimer timer = new DispatcherTimer();
            timer.Tick += (s,ea) =>
            {
                NumRecsLoaded++;
                if (NumRecsLoaded == TotalNumRecs)
                    timer.Stop();
            };
            timer.Interval = new TimeSpan(0, 0, 0, 0, 500);  // 2/sec
            timer.Start();
        }
    }

1074-001

About Sean
Software developer in the Twin Cities area, passionate about .NET technologies. Equally passionate about my own personal projects related to family history and preservation of family stories and photos.

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