Question

我现在正在做一个显示系统中HDD使用情况的应用程序。为此，我想动态生成网格和控件（如进度条和标签）以显示用法。是否有可用于此目的的XAML模板？

Answer 1

我使用下面的代码在我的代码中动态生成控件

Label[] drivesLabel;
Label[] percentageLabel;
ProgressBar[] drivesProgress;
int drivesCount = 0;

private void DrawControls()
{
    try
    {
        // Getting drive list.
        List<DriveInfo> driveList = GetHardDiskDrives();
        drivesCount = driveList.Count;

        // Initializing new Grid.
        Grid drivesGrid = new Grid();
        drivesGrid.Children.Clear();
        DrivesBorder.Child = drivesGrid;

        // Adding Rows and Colums to Grid.
        RowDefinition[] rows = new RowDefinition[2*drivesCount + 1];
        ColumnDefinition[] columns = new ColumnDefinition[6];

        // Draw Rows.
        for (int i = 0; i < 2*drivesCount + 1; i++)
        {
            rows[i] = new RowDefinition();
            drivesGrid.RowDefinitions.Add(rows[i]);

            // Setting Row height.
            rows[i].Height = (0 == i % 2) ? new GridLength( 5 ): new GridLength( 25 );
        }
        // Draw Columns.
        for (int i = 0; i < 6; i++)
        {
            columns[i] = new ColumnDefinition();
            drivesGrid.ColumnDefinitions.Add(columns[i]);
            if (i % 2 == 0)
            {
                // Setting column width.
                columns[i].Width = new GridLength(5);
            }
        }

        // Setting column width.
        columns[1].Width = new GridLength(60);
        columns[3].Width = new GridLength(180);
        columns[5].Width = new GridLength(60);

        // Draw Labels to show drive letters.
        drivesLabel = new Label[drivesCount];

        // Draw Progress bar to show drive usage.
        drivesProgress = new ProgressBar[drivesCount];

        // Draw Labels to show drive usage.
        percentageLabel = new Label[drivesCount];

        // Adding Labels and Progressbars to Grid.
        for (int i = 0, j = 1; i < drivesCount; i++, j++)
        {
            // Initialize Labels to show drives.
            drivesLabel[i] = new Label();
            drivesLabel[i].Content = driveList[i].Name;
            drivesLabel[i].Foreground = Brushes.Navy;
            Grid.SetRow(drivesLabel[i], i + j);
            Grid.SetColumn(drivesLabel[i], 1);
            drivesGrid.Children.Add(drivesLabel[i]);

            // Initialize ProgressBar to show usage.
            drivesProgress[i] = new ProgressBar();
            drivesProgress[i].FlowDirection = FlowDirection.LeftToRight;
            drivesProgress[i].HorizontalAlignment = HorizontalAlignment.Center;
            drivesProgress[i].VerticalAlignment = VerticalAlignment.Center;
            drivesProgress[i].Orientation= Orientation.Horizontal;
            drivesProgress[i].Value = 0;
            drivesProgress[i].Maximum = 100;
            drivesProgress[i].Width = 180;
            drivesProgress[i].Height = 18;
            Grid.SetRow(drivesProgress[i], i + j);
            Grid.SetColumn(drivesProgress[i], 3);
            drivesGrid.Children.Add(drivesProgress[i]);

            // Initialize Labels  to show usage in percentage.
            percentageLabel[i] = new Label();
            percentageLabel[i].Content = "0 %";
            Grid.SetRow(percentageLabel[i], i + j);
            Grid.SetColumn(percentageLabel[i], 5);
            drivesGrid.Children.Add(percentageLabel[i]);

            // Setting window height.
            SetWindowHeight(30);
        }
    }
    catch(Exception Ex) {}
}

函数GetHardDiskDrives（）和SetWindowHeight（）是用户定义的函数。 jpb用于获取硬盘并根据添加的新控件设置窗口高度。

Answer 2

我发现另一个答案令人困惑，因为内联注释...添加一个columnDEFINITION（例如）“draw”绝对没有 - 这对初学者来说是非常误导的。

此外：即使已经选择了行，也会重复选择行...这只会增加无用的开销。如果您使用数百行，这将使您的应用程序真的很慢。

与设置WindowHeight相同。

这是一个（某种程度上）更有效的VB.NET动态行和列管理解决方案：（如果要切换到异步处理，请使用Dispatcher.BeginInvoke（）而不是Invoke（））

Private Delegate Sub MyDelegate3(ByVal iByte As Byte)
Private Delegate Function MyDelegate4() As Byte

Public Property GridColumns As Byte
        Get
            Dim del As New MyDelegate4(AddressOf GetColumns)
            Return grid.Dispatcher.Invoke(del)
        End Get

        Set(ByVal value As Byte)
            Dim del As MyDelegate3
            If GridColumns > 0 Then
                Dim diff As SByte = GridColumns - value
                If diff > 0 Then    'Spalten abziehen
                    del = New MyDelegate3(AddressOf RemColDefs)
                    grid.Dispatcher.Invoke(del, diff)
                Else                'Spalten hinzufügen
                    del = New MyDelegate3(AddressOf AddColDefs)
                    grid.Dispatcher.Invoke(del, Math.Abs(diff))
                End If
            Else
                del = New MyDelegate3(AddressOf AddColDefs)
                grid.Dispatcher.Invoke(del, value)
            End If
        End Set
    End Property

    Public Property GridRows As Byte
        Get
            Dim del As New MyDelegate4(AddressOf GetRows)
            Return grid.Dispatcher.Invoke(del)
        End Get
        Set(value As Byte)
            Dim del As MyDelegate3
            If GridRows > 0 Then
                Dim diff As SByte = GridRows - value
                If diff > 0 Then    'Zeilen abziehen
                    del = New MyDelegate3(AddressOf RemRowDefs)
                    grid.Dispatcher.Invoke(del, diff)
                Else                'Spalten hinzufügen
                    del = New MyDelegate3(AddressOf AddRowDefs)
                    grid.Dispatcher.Invoke(del, Math.Abs(diff))
                End If
            Else
                del = New MyDelegate3(AddressOf AddRowDefs)
                grid.Dispatcher.Invoke(del, value)
            End If
        End Set
    End Property

    Private Function GetRows() As Byte
        Return grid.RowDefinitions.Count
    End Function
    Private Function GetColumns() As Byte
        Return grid.ColumnDefinitions.Count
    End Function

    Private Sub AddRowDefs(ByVal iRows As Byte)
        For r As Byte = 1 To iRows
            Dim rowDef As New RowDefinition
            rowDef.Height = GridLength.Auto
            grid.RowDefinitions.Add(rowDef)
        Next         
    End Sub
    Private Sub RemRowDefs(ByVal iRows As Byte)
        For r As Byte = 1 To iRows
            If grid.RowDefinitions.Count > 0 Then
                grid.RowDefinitions.Remove(grid.RowDefinitions(0))
            End If
        Next            
    End Sub

    Private Sub AddColDefs(ByVal iCols As Byte)
        For r As Byte = 1 To iCols
            Dim colDef As New ColumnDefinition
            colDef.Width = GridLength.Auto
            grid.ColumnDefinitions.Add(colDef)
        Next            
    End Sub
    Private Sub RemColDefs(ByVal iCols As Byte)
        For r As Byte = 1 To iCols
            If grid.ColumnDefinitions.Count > 0 Then
                grid.ColumnDefinitions.Remove(grid.ColumnDefinitions(0))
            End If
        Next            
    End Sub

在WPF中动态添加网格和控件

2 个答案: