在当前的不少电商或者物流等应用程序中,为了清晰的表明某些事件的当前状态,以及历史时序记录情况,经常可以看到一个步骤条控件,它分成几个节点,每个节点代表一个核心状态,每个状态之间通过线条进行连接,以经过的节点高亮显示,未经过的线条灰度显示。其中,每个节点下可以通过文字进行简要的描述。本文将利用C#中的GDI+技术,自动绘制相关的UI元素,实现Window Form的步骤条控件。
1 项目结构
利用Visual Studio 社区版,创建一个Window应用程序项目WinControls,其中在资源文件中添加一个图形,用于绘制经过步骤条节点的✔ 状态。并添加几个类,具体项目结构如下图所示:
其中的check_lightblue.png图片代表的是✔ 状态。可以通过Properties.Resources.check_lightblue进行访问。eumStepState.cs是一个枚举类型,表示节点的状态信息,核心代码如下:
namespace WinControls { public enum eumStepState { Waiting, Completed, OutTime } }
而 StepEntity.cs 文件是代表一个步骤条节点的实体对象,其中具备的属性有节点ID,节点名称,节点状态,节点顺序,节点描述等,核心代码如下:
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace WinControls { public class StepEntity { public string Id { get; set; } public string StepName { get; set; } public int StepOrder { get; set; } public eumStepState StepState { get; set; } public string StepDesc { get; set; } public object StepTag { get; set; } public StepEntity(string id, string stepname, int steporder, string stepdesc, eumStepState stepstate, object tag) { this.Id = id; this.StepName = stepname; this.StepOrder = steporder; this.StepDesc = stepdesc; this.StepTag = tag; this.StepState = stepstate; } } }
2 步骤条实现
在项目WinControls中添加一个名为StepViewer的用户控件,具体如下图所示:
核心代码如下:
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; namespace WinControls { public partial class StepViewer : UserControl { public StepViewer() { InitializeComponent(); this.Height = 68; this.Paint += StepViewer_Paint; } private List<StepEntity> _dataSourceList = null; private Color _Gray = Color.FromArgb(189, 195, 199); private Color _DarkGray = Color.FromArgb(149, 165, 166); private Color _Blue = Color.FromArgb(52, 152, 219); private Color _Red = Color.FromArgb(231, 76, 60); [Browsable(true), Category("StepViewer")] public List<StepEntity> ListDataSource { get { return _dataSourceList; } set { if (_dataSourceList != value) { _dataSourceList = value; Invalidate(); } } } private int _currentStep = 0; public int CurrentStep { get { return _currentStep; } set { if (_currentStep != value) { _currentStep = value; Invalidate(); } } } private void StepViewer_Paint(object sender, PaintEventArgs e) { if (this.ListDataSource != null) { int CenterY = this.Height / 2; int index = 1; int count = ListDataSource.Count; int lineWidth = 120; int StepNodeWH = 28; //this.Width = 32 * count + lineWidth * (count - 1) + 6+300; //defalut pen & brush e.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; Brush brush = new SolidBrush(_Gray); Pen p = new Pen(brush, 1f); Brush brushNode = new SolidBrush(_DarkGray); Pen penNode = new Pen(brushNode, 1f); Brush brushNodeCompleted = new SolidBrush(_Blue); Pen penNodeCompleted = new Pen(brushNodeCompleted, 1f); int initX = 6; //string Font nFont = new Font("微软雅黑", 12); Font stepFont = new Font("微软雅黑", 11, FontStyle.Bold); int NodeNameWidth = 0; foreach (var item in ListDataSource) { //round Rectangle rec = new Rectangle(initX, CenterY - StepNodeWH / 2, StepNodeWH, StepNodeWH); if (CurrentStep == item.StepOrder) { if (item.StepState == eumStepState.OutTime) { e.Graphics.DrawEllipse(new Pen(_Red, 1f), rec); e.Graphics.FillEllipse(new SolidBrush(_Red), rec); } else { e.Graphics.DrawEllipse(penNodeCompleted, rec); e.Graphics.FillEllipse(brushNodeCompleted, rec); } //白色字体 SizeF fTitle = e.Graphics.MeasureString(index.ToString(), stepFont); Point pTitle = new Point(initX + StepNodeWH / 2 - (int)Math.Round(fTitle.Width) / 2, CenterY - (int)Math.Round(fTitle.Height / 2)); e.Graphics.DrawString(index.ToString(), stepFont, Brushes.White, pTitle); //nodeName SizeF sNode = e.Graphics.MeasureString(item.StepName, nFont); Point pNode = new Point(initX + StepNodeWH, CenterY - (int)Math.Round(sNode.Height / 2) + 2); e.Graphics.DrawString(item.StepName, new Font(nFont, FontStyle.Bold), brushNode, pNode); NodeNameWidth = (int)Math.Round(sNode.Width); if (index < count) { e.Graphics.DrawLine(p, initX + StepNodeWH + NodeNameWidth, CenterY, initX + StepNodeWH + NodeNameWidth + lineWidth, CenterY); } } else if (item.StepOrder < CurrentStep) { //completed e.Graphics.DrawEllipse(penNodeCompleted, rec); //image RectangleF recRF = new RectangleF(rec.X + 6, rec.Y + 6, rec.Width - 12, rec.Height - 12); e.Graphics.DrawImage(Properties.Resources.check_lightblue, recRF); //nodeName SizeF sNode = e.Graphics.MeasureString(item.StepName, nFont); Point pNode = new Point(initX + StepNodeWH, CenterY - (int)Math.Round(sNode.Height / 2) + 2); e.Graphics.DrawString(item.StepName, nFont, brushNode, pNode); NodeNameWidth = (int)Math.Round(sNode.Width); if (index < count) { e.Graphics.DrawLine(penNodeCompleted, initX + StepNodeWH + NodeNameWidth, CenterY, initX + StepNodeWH + NodeNameWidth + lineWidth, CenterY); } } else { e.Graphics.DrawEllipse(p, rec); // SizeF fTitle = e.Graphics.MeasureString(index.ToString(), stepFont); Point pTitle = new Point(initX + StepNodeWH / 2 - (int)Math.Round(fTitle.Width) / 2, CenterY - (int)Math.Round(fTitle.Height / 2)); e.Graphics.DrawString(index.ToString(), stepFont, brush, pTitle); //nodeName SizeF sNode = e.Graphics.MeasureString(item.StepName, nFont); Point pNode = new Point(initX + StepNodeWH, CenterY - (int)Math.Round(sNode.Height / 2) + 2); e.Graphics.DrawString(item.StepName, nFont, brushNode, pNode); NodeNameWidth = (int)Math.Round(sNode.Width); if (index < count) { //line e.Graphics.DrawLine(p, initX + StepNodeWH + NodeNameWidth, CenterY, initX + StepNodeWH + NodeNameWidth + lineWidth, CenterY); } } //描述信息 if (item.StepDesc != "") { Point pNode = new Point(initX + StepNodeWH, CenterY + 10); e.Graphics.DrawString(item.StepDesc, new Font(nFont.FontFamily, 10), brush, pNode); } index++; //8 is space width initX = initX + lineWidth + StepNodeWH + NodeNameWidth + 8; } } } } }
其中,首先定义了一组颜色,代码如下:
private Color _Gray = Color.FromArgb(189, 195, 199); private Color _DarkGray = Color.FromArgb(149, 165, 166); private Color _Blue = Color.FromArgb(52, 152, 219); private Color _Red = Color.FromArgb(231, 76, 60);
其次,由于步骤条的节点有多个,是一个列表,因此这里用private List<StepEntity> _dataSourceList = null;进行定义一个数据源。[Browsable(true), Category("StepViewer")]则表示ListDataSource属性在控件的属性列表中可见。在赋值后会调用 Invalidate()方法进行UI重绘。
再次,此控件初始化时,执行如下代码:
public StepViewer() { InitializeComponent(); this.Height = 68; this.Paint += StepViewer_Paint; }
即限定控件的高度为68,同时绑定绘制事件Paint,实现绘制的方法为 StepViewer_Paint,这是控件的核心,其中使用了 e.Graphics下的API可以绘制圆形,线条和图片,以及文本信息。
3 步骤条效果
将控件添加到Form1窗口上并在初始化方法中维护数据源信息,核心代码如下:
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; namespace WinControls { public partial class Form1 : Form { public Form1() { InitializeComponent(); this.BackColor = Color.White; } private void Form1_Load(object sender, EventArgs e) { List<StepEntity> list = new List<StepEntity>(); list.Add(new StepEntity("1", "新开单", 1, "这里是该步骤的描述信息", eumStepState.Completed, null)); list.Add(new StepEntity("2", "主管审批", 2, "这里是该步骤的描述信息", eumStepState.Waiting, null)); list.Add(new StepEntity("3", "总经理审批", 3, "这里是该步骤的描述信息", eumStepState.OutTime, null)); list.Add(new StepEntity("2", "完成", 4, "这里是该步骤的描述信息", eumStepState.Waiting, null)); this.stepViewer1.CurrentStep = 3; this.stepViewer1.ListDataSource = list; } private void button1_Click(object sender, EventArgs e) { this.stepViewer1.CurrentStep--; } private void button2_Click(object sender, EventArgs e) { this.stepViewer1.CurrentStep++; } } }
执行项目,Form1界面具体如下图所示: