Po odebraniu danych robię aktualizacje dataGridView.
foreach (var zdarzenia in awarie_gotowe)
{
dataGridView1.Rows.Add(zdarzenia.data_awari, zdarzenia.awaria);
}
Wszystko ładnie pięknie ale tylko za 1 razem. Potem dataGrid się nie odświeża.
Próbowałem dodać przed forech
dataGridView1.Rows.Clear();
ale efekt jest tylko taki, że grid zostaje pusty...
Proszę o porady
Witaj,
Zainteresuj się czym jest ObservableCollection. Są to specjalizowane rodzaje kolekcji, które posiadają automatyczny mechanizm rozgłaszania zmian w nich dokonanych. Przykładowo:
using System;
using System.Collections.ObjectModel;
using System.Windows.Input;
using Accidens.App.Common;
using Accidens.App.Data.Model;
using Accidens.App.ViewModels;
namespace Accidens.App
{
public partial class MainWindow
{
public MainWindow()
{
InitializeComponent();
DataContext = new AccidentsViewModel();
}
}
namespace Data.Model
{
// Awaria
public class Accident
{
public DateTime Created { get; set; } //Utworzono
public Guid AccidentKindId { get; set; } //Identyfikator rodzaju awarii
}
}
namespace ViewModels
{
public class AccidentsViewModel
{
public ObservableCollection<Accident> DoneAccidents { get; set; }
public ICommand AddAccidentCommand { get; set; }
public AccidentsViewModel()
{
DoneAccidents = new ObservableCollection<Accident>
{
new Accident()
{
Created = new DateTime(2015, 8, 11, 22, 15, 0),
AccidentKindId = new Guid("7e4f364f-c3ae-40a7-b38f-5d54ec820b95")
},
new Accident()
{
Created = new DateTime(2015, 8, 11, 22, 18, 0),
AccidentKindId = new Guid("7e4f364f-c3ae-40a7-b38f-5d54ec820b95")
},
new Accident()
{
Created = new DateTime(2015, 8, 11, 22, 22, 0),
AccidentKindId = new Guid("bdac1b08-716e-47ee-9eae-91b114235103")
}
};
AddAccidentCommand = new RelayCommand(AddAccident);
}
public void AddAccident()
{
DoneAccidents.Add(new Accident()
{
Created = new DateTime(2015, 8, 11, 22, 15, 0),
AccidentKindId = new Guid("7e4f364f-c3ae-40a7-b38f-5d54ec820b95")
});
}
}
}
namespace Common
{
public class RelayCommand : ICommand
{
private readonly Action _execute;
private readonly Func<bool> _canExecute;
/// <summary>
/// Raised when RaiseCanExecuteChanged is called.
/// </summary>
public event EventHandler CanExecuteChanged;
/// <summary>
/// Creates a new command that can always execute.
/// </summary>
/// <param name="execute">The execution logic.</param>
public RelayCommand(Action execute)
: this(execute, null)
{
}
/// <summary>
/// Creates a new command.
/// </summary>
/// <param name="execute">The execution logic.</param>
/// <param name="canExecute">The execution status logic.</param>
public RelayCommand(Action execute, Func<bool> canExecute)
{
if (execute == null)
throw new ArgumentNullException("execute");
_execute = execute;
_canExecute = canExecute;
}
/// <summary>
/// Determines whether this <see cref="RelayCommand"/> can execute in its current state.
/// </summary>
/// <param name="parameter">
/// Data used by the command. If the command does not require data to be passed, this object can be set to null.
/// </param>
/// <returns>true if this command can be executed; otherwise, false.</returns>
public bool CanExecute(object parameter)
{
return _canExecute == null || _canExecute();
}
/// <summary>
/// Executes the <see cref="RelayCommand"/> on the current command target.
/// </summary>
/// <param name="parameter">
/// Data used by the command. If the command does not require data to be passed, this object can be set to null.
/// </param>
public void Execute(object parameter)
{
_execute();
}
/// <summary>
/// Method used to raise the <see cref="CanExecuteChanged"/> event
/// to indicate that the return value of the <see cref="CanExecute"/>
/// method has changed.
/// </summary>
public void RaiseCanExecuteChanged()
{
var handler = CanExecuteChanged;
if (handler != null)
{
handler(this, EventArgs.Empty);
}
}
}
}
}
i xaml:
<Window x:Class="Accidens.App.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:viewModels="clr-namespace:Accidens.App.ViewModels"
d:DataContext="{d:DesignInstance viewModels:AccidentsViewModel, d:IsDesignTimeCreatable=True}"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525" >
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="30" />
</Grid.RowDefinitions>
<DataGrid
Grid.Row="0"
ItemsSource="{Binding DoneAccidents}"
AutoGenerateColumns="True" />
<Button Grid.Row="1" Command="{Binding AddAccidentCommand}" Content="Dodaj" Width="100" HorizontalAlignment="Right" />
</Grid>
</Window>
Warto zapoznać się z np. wzorcem MVVM i zacząć wykorzystywać dedykowane sposoby wiązania danych.
Pozdrawiam,
Maciej
Qrcze! Jakoś się zasugerowałem, że piszesz w WPF :)
Nie dużo pamiętam z WinFormsów, ale zamiast ObservableCollecton trzeba zastosować BindingList, a kod pozostanie podobny:
using System;
using System.ComponentModel;
using System.Windows.Forms;
using WindowsFormsApplication1.Data.Model;
using WindowsFormsApplication1.ViewModels;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
private readonly AccidentsViewModel _viewModel;
public Form1()
{
InitializeComponent();
_viewModel = new AccidentsViewModel();
dataGridView2.DataSource = _viewModel.DoneAccidents;
}
private void AddAccident_Click(object sender, EventArgs e)
{
_viewModel.AddAccident();
}
}
namespace Data.Model
{
// Awaria
public class Accident
{
public DateTime Created { get; set; } //Utworzono
public Guid AccidentKindId { get; set; } //Identyfikator rodzaju awarii
}
}
namespace ViewModels
{
public class AccidentsViewModel
{
public BindingList<Accident> DoneAccidents { get; set; }
public AccidentsViewModel()
{
DoneAccidents = new BindingList<Accident>
{
new Accident()
{
Created = new DateTime(2015, 8, 11, 22, 15, 0),
AccidentKindId = new Guid("7e4f364f-c3ae-40a7-b38f-5d54ec820b95")
},
new Accident()
{
Created = new DateTime(2015, 8, 11, 22, 18, 0),
AccidentKindId = new Guid("7e4f364f-c3ae-40a7-b38f-5d54ec820b95")
},
new Accident()
{
Created = new DateTime(2015, 8, 11, 22, 22, 0),
AccidentKindId = new Guid("bdac1b08-716e-47ee-9eae-91b114235103")
}
};
}
public void AddAccident()
{
DoneAccidents.Add(new Accident()
{
Created = new DateTime(2015, 8, 11, 22, 15, 0),
AccidentKindId = new Guid("7e4f364f-c3ae-40a7-b38f-5d54ec820b95")
});
}
}
}
}
M.