如何使用TreeViewDrawMode.OwnerDrawAll改变选定节点的背景颜色的TreeView？ [英] How to change background color of selected node in TreeView using TreeViewDrawMode.OwnerDrawAll?

问题描述

我要改回选择的节点，颜色时选择的节点和具有焦点 - 背景色进行绿色选择时，但没有焦点 - 红色。我不能让重点是树视图和没有选择的节点之间的差异。位于TabPage的对象树视图。

  // ...
this.myTreeView.HideSelection = FALSE;
// ...
私人无效myTreeView_drawNode（对象发件人，DrawTreeNodeEventArgs E）
{
      颜色backColorSelected = System.Drawing.Color.Green;
      色背景色= System.Drawing.Color.Red;
      //节点选择与具有焦点
      如果（（（e.State＆安培;！TreeNodeStates.Selected）= 0）
      ＆功放;＆安培; （this.myTabControl.Focused））//这不工作，节点总是冲
      {
          使用（SolidBrush刷=新SolidBrush（backColorSelected））
          {
              e.Graphics.FillRectangle（刷，e.Bounds）;
          }
      }
      //选择的节点，但是没有焦点
      否则如果（（e.State＆安培;！TreeNodeStates.Selected）= 0）
      {
          使用（SolidBrush刷=新SolidBrush（背景色））
          {
             e.Graphics.FillRectangle（刷，e.Bounds）;
          }
      }
      //没有选择可言
      其他
      {
          e.Graphics.FillRectangle（Brushes.White，e.Bounds）;
      }

      e.Graphics.DrawRectangle（SystemPens.Control，e.Bounds）;

      TextRenderer.DrawText（e.Graphics，
                             e.Node.Text，
                             e.Node.TreeView.Font，
                             e.Node.Bounds，
                             e.Node.ForeColor）;
}
 

解决方案

只要检查该节点的属性，它的工作原理（测试）。此外，我建议缓存任何自定义画笔，你喜欢做以下。（当然你也可以使用Brushes.Red和Brushes.Green）

  SolidBrush greenBrush =新SolidBrush（Color.Green）;
    SolidBrush redBrush =新SolidBrush（Color.Red）;

    私人无效myTreeView_drawNode（对象发件人，DrawTreeNodeEventArgs E）
    {
        如果（e.Node.IsSelected）
        {
            如果（treeView1.Focused）
                e.Graphics.FillRectangle（greenBrush，e.Bounds）;
            其他
                e.Graphics.FillRectangle（redBrush，e.Bounds）;
        }
        其他
            e.Graphics.FillRectangle（Brushes.White，e.Bounds）;

        e.Graphics.DrawRectangle（SystemPens.Control，e.Bounds）;

        TextRenderer.DrawText（e.Graphics，
                               e.Node.Text，
                               e.Node.TreeView.Font，
                               e.Node.Bounds，
                               e.Node.ForeColor）;
    }
 

P.S。你可能需要渲染你单击展开节点等东西。

I need to change back colours of selected nodes, when node selected and has focus - back color make green, when selected but doesn't have focus - red. I can't make the difference between selected node with focus on tree view and without. Tree view located in TabPage object.

//...
this.myTreeView.HideSelection = false;
//...
private void myTreeView_drawNode(object sender, DrawTreeNodeEventArgs e)
{
      Color backColorSelected = System.Drawing.Color.Green;
      Color backColor = System.Drawing.Color.Red;
      // node selected and has focus
      if (((e.State & TreeNodeStates.Selected) != 0) 
      && (this.myTabControl.Focused)) // this doesn't work, node is always red
      {
          using (SolidBrush brush = new SolidBrush(backColorSelected))
          {
              e.Graphics.FillRectangle(brush, e.Bounds);
          }
      }
      // node selected but doesn't have focus
      else if ((e.State & TreeNodeStates.Selected) != 0)
      {
          using (SolidBrush brush = new SolidBrush(backColor))
          {
             e.Graphics.FillRectangle(brush, e.Bounds);
          }
      }
      // not selected at all
      else
      {
          e.Graphics.FillRectangle(Brushes.White, e.Bounds);
      }

      e.Graphics.DrawRectangle(SystemPens.Control, e.Bounds);

      TextRenderer.DrawText(e.Graphics,
                             e.Node.Text,
                             e.Node.TreeView.Font,
                             e.Node.Bounds,
                             e.Node.ForeColor);
}   

解决方案

Just check the node's property, it works (tested). Also I suggest caching any custom brushes you make like the following.. (Of course you can also use Brushes.Red and Brushes.Green)

SolidBrush greenBrush = new SolidBrush(Color.Green);
    SolidBrush redBrush = new SolidBrush(Color.Red);

    private void myTreeView_drawNode(object sender, DrawTreeNodeEventArgs e)
    {
        if (e.Node.IsSelected)
        {
            if (treeView1.Focused)
                e.Graphics.FillRectangle(greenBrush, e.Bounds);
            else
                e.Graphics.FillRectangle(redBrush, e.Bounds);
        }
        else
            e.Graphics.FillRectangle(Brushes.White, e.Bounds);

        e.Graphics.DrawRectangle(SystemPens.Control, e.Bounds);

        TextRenderer.DrawText(e.Graphics,
                               e.Node.Text,
                               e.Node.TreeView.Font,
                               e.Node.Bounds,
                               e.Node.ForeColor);
    }

P.S. You'll probably need to render something that you click to expand nodes etc.

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