Question

我正在使用Microsoft的这个教程在我的dataGridView中实现一个自定义的NumericUpDown单元格：https://msdn.microsoft.com/en-us/library/aa730881(v=vs.80).aspx

它运行良好，但问题是当我不编辑它的值时，我的表单/网格开始像疯了一样轻弹，当我点击编辑它停止的值时。

我的表格已经“双重缓冲”了，所以我不知道该怎么做。

代码可以在上面的链接中找到，但是我发布了两个我正在使用它的类：

http://pastebin.com/bdhWbgJU 和 http://pastebin.com/FeH3qHEb

Answer 1

在pastebin中发布的代码似乎过于复杂。您可能想尝试重写控件。我为你创建了一个模板，简单版本似乎没有任何闪烁。

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Windows.Forms;

    namespace Opulos.Core.UI {

    public class FormDgvNud : Form {
        DataGridView dgv = new DataGridViewNumericUpDown { Dock = DockStyle.Fill };
        public FormDgvNud() {
            Controls.Add(dgv);
        }
    }

    public class DataGridViewNumericUpDown : DataGridView {
        public DataGridViewNumericUpDown() : base() {
            Columns.Add(new NumericUpDownColumn() { HeaderText = "NUD1", DataPropertyName = "Column1", Name = "Column1" });
            Rows.Add();
        }
    }

    public class NumericUpDownColumn : DataGridViewColumn {

        public NumericUpDownColumn() : base(new NumericUpDownCell()) {
            this.ValueType = typeof(decimal?);
        }

        public override DataGridViewCell CellTemplate {
            get {
                return base.CellTemplate;
            }
            set {
                if (!(value is NumericUpDownCell))
                    throw new InvalidCastException("Must be a NumericUpDownCell");

                base.CellTemplate = value;
            }
        }
    }

    public class NumericUpDownCell : DataGridViewTextBoxCell {

        public override void InitializeEditingControl(int rowIndex, Object initialFormattedValue, DataGridViewCellStyle dataGridViewCellStyle) {
            // required to initialize the editing control:
            base.InitializeEditingControl(rowIndex, initialFormattedValue, dataGridViewCellStyle);
            var ctl = (NumericUpDownEditingControl) DataGridView.EditingControl;
            //NumericUpDownColumn cc = (NumericUpDownColumn) this.OwningColumn;
            if (this.Value == null || this.Value == DBNull.Value) {
                ctl.Value = (ctl.Minimum <= 0 && ctl.Maximum >= 0 ? 0 : ctl.Minimum);
            }
            else {
                Object trueValue = this.Value;
                ctl.Value = (decimal) trueValue;
            }
        }

        public override Type EditType {
            get {
                return typeof(NumericUpDownEditingControl);
            }
        }

        public override Type ValueType {
            get {
                return base.ValueType;
            }
            set {
                base.ValueType = value;
            }
        }

        public override Object DefaultNewRowValue {
            get {
                return DBNull.Value;
            }
        }
    }

    public class NumericUpDownEditingControl : NumericUpDown, IDataGridViewEditingControl {

        private bool Cancelling = false;

        public NumericUpDownEditingControl() {
        }

        // Implements the IDataGridViewEditingControl.EditingControlFormattedValue property.
        public Object EditingControlFormattedValue {
            get {
                // must return a String
                // it doesn't matter if the value is formatted, it will be replaced
                // by the formatting events
                String s = "" + this.Value.ToString();
                return s;
            }

            set {
                decimal val = 0;
                if (value is decimal)
                    this.Value = (decimal) value;
                else {
                    String s = "" + value;
                    if (s.Length > 0) {
                        if (decimal.TryParse(s, System.Globalization.NumberStyles.Any, System.Globalization.CultureInfo.CurrentCulture, out val))
                            this.Value = val;
                    }
                }
            }
        }

        protected override void OnLeave(EventArgs e) {
            if (!Cancelling) {
                var dgv = this.EditingControlDataGridView;
                var cell = (NumericUpDownCell) dgv.CurrentCell;
                cell.Value = this.Value;
            }

            base.OnLeave(e);
            Cancelling = false;
        }

        private void ProcessValue(Direction transferFocusDirection) {
            var dgv = this.EditingControlDataGridView;
            var cell = (NumericUpDownCell) dgv.CurrentCell;

            if (!Cancelling)
                cell.Value = this.Value;
        }

        protected override void OnKeyDown(KeyEventArgs e) {
            if (e.KeyCode == Keys.Escape) {
                Cancelling = true;
                e.Handled = true;
                e.SuppressKeyPress = true;
                var dgv = this.EditingControlDataGridView;
                dgv.CancelEdit();
                dgv.EndEdit();
            }

            base.OnKeyDown(e);
        }

        // Implements the  IDataGridViewEditingControl.GetEditingControlFormattedValue method. 
        public Object GetEditingControlFormattedValue(DataGridViewDataErrorContexts context) {
            return EditingControlFormattedValue;
        }

        // Implements the IDataGridViewEditingControl.ApplyCellStyleToEditingControl method. 
        public void ApplyCellStyleToEditingControl(DataGridViewCellStyle dataGridViewCellStyle) {
            this.Font = dataGridViewCellStyle.Font;
            this.ForeColor = dataGridViewCellStyle.ForeColor;
            this.BackColor = dataGridViewCellStyle.BackColor;
        }

        // Implements the IDataGridViewEditingControl.EditingControlRowIndex property. 
        public int EditingControlRowIndex { get; set; }

        // Implements the IDataGridViewEditingControl.EditingControlWantsInputKey method. 
        public bool EditingControlWantsInputKey(Keys key, bool dataGridViewWantsInputKey) {
            switch (key & Keys.KeyCode) {
                case Keys.Left:
                case Keys.Up:
                case Keys.Down:
                case Keys.Right:
                case Keys.Home:
                case Keys.End:
                case Keys.PageDown:
                case Keys.PageUp:
                case Keys.Escape:
                    return true;
                default:
                    return !dataGridViewWantsInputKey;
            }
        }

        // Implements the IDataGridViewEditingControl.PrepareEditingControlForEdit method. 
        public void PrepareEditingControlForEdit(bool selectAll) {
            // No preparation needs to be done.
        }

        // Implements the IDataGridViewEditingControl.RepositionEditingControlOnValueChange property. 
        public bool RepositionEditingControlOnValueChange {
            get {
                return false;
            }
        }

        // Implements the IDataGridViewEditingControl.EditingControlDataGridView property. 
        public DataGridView EditingControlDataGridView { get; set; }

        // Implements the IDataGridViewEditingControl.EditingControlValueChanged property. 
        public bool EditingControlValueChanged { get; set; }

        // Implements the IDataGridViewEditingControl.EditingPanelCursor property. 
        public Cursor EditingPanelCursor {
            get {
                return base.Cursor;
            }
        }
    }


public enum Direction {
    Down = 0,
    Right,
    Up,
    Left,
    None
}
    }

自定义NumericUpDown单元格闪烁

1 个答案: