Question

所以，我有一个DataGridView，在这个表中有文本，最后一列是显示百分比的Progess Bar。我已经实现了DataGridViewProgressCell的修改版本，我找到了（如果我没记错的话）MSDN。此实现的源代码如下所示。

    public class DataGridViewProgressColumn : DataGridViewImageColumn
    {
        public DataGridViewProgressColumn()
        {
            CellTemplate = new DataGridViewProgressCell();
        }
    }
    public class DataGridViewProgressCell : DataGridViewImageCell
    {
        // Used to make custom cell consistent with a DataGridViewImageCell
        static Image emptyImage;
        static DataGridViewProgressCell()
        {
            emptyImage = new Bitmap(1, 1, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
        }
        public DataGridViewProgressCell()
        {
            this.ValueType = typeof(int);
        }
        protected override object GetFormattedValue(object value, int rowIndex, ref DataGridViewCellStyle cellStyle, TypeConverter valueTypeConverter, TypeConverter formattedValueTypeConverter, DataGridViewDataErrorContexts context)
        {
            return emptyImage;
        }

        protected override void Paint(System.Drawing.Graphics g, System.Drawing.Rectangle clipBounds, System.Drawing.Rectangle cellBounds, int rowIndex, DataGridViewElementStates cellState, object value, object formattedValue, string errorText, DataGridViewCellStyle cellStyle, DataGridViewAdvancedBorderStyle advancedBorderStyle, DataGridViewPaintParts paintParts)
        {
            double progressVal = 0.0;

            if (value != null)
                progressVal = Convert.ToDouble(this.Value);

            float percentage = ((float)progressVal / 100.0f); // Need to convert to float before division; otherwise C# returns int which is 0 for anything but 100%.
            Brush backColorBrush = new SolidBrush(cellStyle.BackColor);
            Brush foreColorBrush = new SolidBrush(cellStyle.ForeColor);
            // Draws the cell grid
            base.Paint(g, clipBounds, cellBounds,
             rowIndex, cellState, value, formattedValue, errorText,
             cellStyle, advancedBorderStyle, (paintParts & ~DataGridViewPaintParts.ContentForeground));
            if (percentage > 0.0)
            {
                // Draw the progress bar and the text
                g.FillRectangle(new SolidBrush(Color.FromArgb(163, 189, 242)), cellBounds.X + 2, cellBounds.Y + 2, Convert.ToInt32((percentage * cellBounds.Width - 4)), cellBounds.Height - 4);
                g.DrawString(progressVal.ToString() + "%", cellStyle.Font, foreColorBrush, cellBounds.X + 6, cellBounds.Y + 2);
            }
            else
            {
                // draw the text
                if (this.DataGridView.CurrentRow.Index == rowIndex)
                    g.DrawString(progressVal.ToString() + "%", cellStyle.Font, new SolidBrush(cellStyle.SelectionForeColor), cellBounds.X + 6, cellBounds.Y + 2);
                else
                    g.DrawString(progressVal.ToString() + "%", cellStyle.Font, foreColorBrush, cellBounds.X + 6, cellBounds.Y + 2);
            }
        }
    }

它在我的DataGridView中创建了一个漂亮的小进度条。只有一个问题......我无法弄清楚如何根据值的范围更改进度条的颜色，并且此值可能会根据生成的报告类型而更改DataGridView。例如，在一份报告中，如果百分比低于50％，则需要为红色，50-80％，黄色和80％以上，绿色，但在不同的报告中，阈值可能为40％和70％。我无法弄清楚如何将这些值传递给DataGridViewProgressCell。我的实现如下。谢谢你的帮助！

private void fillData() { dataGridView1.Columns.Clear(); dataGridView1.Rows.Clear(); dataGridView1.Columns.Add("Header1", "Header1"); dataGridView1.Columns.Add("Header2", "Header2"); dataGridView1.Columns.Add("Header3", "Header3"); dataGridView1.Columns.Add("Header4", "Header4"); dataGridView1.Columns.Add(new DataGridViewProgressColumn()); try { //jsonManager is a simple WebClient. Nothing fancy //The data is in a JSON format, first part of code handles getting the values needed for the table. JavaScriptSerializer js = new JavaScriptSerializer(); string getData = serverURL + "/data"; string htmlGET = jsonManager.DownloadString(getData); object[] myVals = (object[])js.DeserializeObject(htmlGET); Dictionary<string, object> overall = (Dictionary<string, object>)myVals[0]; for (int i = 0; i < myVals .Length; i++) { Dictionary<string, object> entry = (Dictionary<string, object>)myVals [i]; string fooHeader = ""; double percent = Convert.ToDouble(entry["percent"]); int acceptable = (int)entry["acceptable"]; int total_foo = (int)entry["total_welds"]; if (i == 0) sch = "OverallFoo"; else sch = ((int)entry["fooHeader"]).ToString(); dataGridView1.Rows.Add(new object[] { sch, percent, acceptable, total_welds, percent }); } } catch(Exception e) { //Handle exception(s) } finally { //More steps, including log writing. } }

Answer 1

如果我正确理解了您的问题，那么我们只需要一个位置来存储确定进度条颜色的百分比。然后在Paint（）方法中使用它。这就是我要做的事情：

我在ProgressColumn中添加了两个属性：

public class DataGridViewProgressColumn : DataGridViewImageColumn
{
    public float RedUntil { get; set; }
    public float YellowUntil { get; set; }

    public DataGridViewProgressColumn()
    {
        CellTemplate = new DataGridViewProgressCell();
    }
}

然后我更改了您的单元格绘图代码：

        var progressColumn = this.DataGridView.Columns[this.ColumnIndex] as DataGridViewProgressColumn;

        if (percentage > 0.0 && progressColumn != null)
        {
            // Draw the progress bar and the text
            Brush fillColor;
            if (percentage < progressColumn.RedUntil)
            {
                fillColor = new SolidBrush(Color.Red);
            }
            else if (percentage < progressColumn.YellowUntil)
            {
                fillColor = new SolidBrush(Color.Yellow);
            }
            else
            {
                fillColor = new SolidBrush(Color.Green);
            }

            g.FillRectangle(fillColor, cellBounds.X + 2, cellBounds.Y + 2, Convert.ToInt32((percentage * cellBounds.Width - 4)), cellBounds.Height - 4);
            g.DrawString(progressVal.ToString() + "%", cellStyle.Font, foreColorBrush, cellBounds.X + 6, cellBounds.Y + 2);
        }
        else

这就是你如何使用它：

        dataGridView1.Columns.Add(new DataGridViewProgressColumn { RedUntil = 0.5f, YellowUntil = 0.75f });

DataGridView中的颜色更改进度条

1 个答案: