ContextMenuStrip.Owner属性空当检索从嵌套ToolStripMenuItem

问题描述

我有一个的ContextMenuStrip 设置有两个的ToolStripItem 秒。第二个的ToolStripItem 有两个额外的嵌套的ToolStripItem 秒。我把它称之为：

I have a ContextMenuStrip setup with two ToolStripItems. The second ToolStripItem has two additional nested ToolStripItems. I define this as:

ContextMenuStrip cms = new ContextMenuStrip();
ToolStripMenuItem contextJumpTo = new ToolStripMenuItem();
ToolStripMenuItem contextJumpToHeatmap = new ToolStripMenuItem();
ToolStripMenuItem contextJumpToHeatmapStart = new ToolStripMenuItem();
ToolStripMenuItem contextJumpToHeatmapLast = new ToolStripMenuItem();

cms.Items.AddRange(new ToolStripItem[] { contextJumpTo,
                                         contextJumpToHeatmap});
cms.Size = new System.Drawing.Size(176, 148);

contextJumpTo.Size = new System.Drawing.Size(175, 22);
contextJumpTo.Text = "Jump To (No Heatmapping)";

contextJumpToHeatmap.Size = new System.Drawing.Size(175, 22);
contextJumpToHeatmap.Text = "Jump To (With Heatmapping)";
contextJumpToHeatmap.DropDownItems.AddRange(new ToolStripItem[] { contextJumpToHeatmapStart, 
                                                                  contextJumpToHeatmapLast });

contextJumpToHeatmapStart.Size = new System.Drawing.Size(165, 22);
contextJumpToHeatmapStart.Text = "From Start of File";

contextJumpToHeatmapLast.Size = new System.Drawing.Size(165, 22);
contextJumpToHeatmapLast.Text = "From Last Data Point";

我再设置一个事件侦听器为三 ToolStripMenuItem s表示我想回应的单击事件。以下是方法（我只列出了两个三种方法）：

I then setup an event listener for the click events of the three ToolStripMenuItems that I want to respond to. Here are the methods (I only listed two of the three methods):

void contextJumpTo_Click(object sender, EventArgs e)
{
    // Try to cast the sender to a ToolStripItem 
    ToolStripMenuItem menuItem = sender as ToolStripMenuItem;
    if (menuItem != null)
    {
        // Retrieve the ContextMenuStrip that owns this ToolStripItem 
        ContextMenuStrip owner = menuItem.Owner as ContextMenuStrip;
        if (owner != null)
        {
            // Get the control that is displaying this context menu 
            DataGridView dgv = owner.SourceControl as DataGridView;
            if (dgv != null)
                // DO WORK
        }
    } 
}

void contextJumpToHeatmapStart_Click(object sender, EventArgs e)
{
    // Try to cast the sender to a ToolStripItem 
    ToolStripMenuItem menuItem = sender as ToolStripMenuItem;
    if (menuItem != null)
    {
        // Retrieve the ToolStripItem that owns this ToolStripItem 
        ToolStripMenuItem ownerItem = menuItem.OwnerItem as ToolStripMenuItem;
        if (ownerItem != null)
        {
            // Retrieve the ContextMenuStrip that owns this ToolStripItem 
            ContextMenuStrip owner = ownerItem.Owner as ContextMenuStrip;
            if (owner != null)
            {
                // Get the control that is displaying this context menu 
                DataGridView dgv = owner.SourceControl as DataGridView;
                if (dgv != null)
                    // DO WORK
            }
        }
    }
}

下面是这个问题，我有：

Here is the issue I have:

我的 contextJumpTo_Click 方法工作完全正常。我们得到了一路下跌的地方，我确定哪些的DataGridView 点击从哪里来的，我可以继续进行。该 contextJumpTo ToolStripMenuItem 然而，而不是在一个嵌套的菜单项的ContextMenuStrip 。

My contextJumpTo_Click method works perfectly fine. We get all the way down to where I determine which DataGridView the click came from and I can proceed. The contextJumpTo ToolStripMenuItem is, however, NOT a nested menu item on the ContextMenuStrip.

但我的方法 contextJumpToHeatmapStart_Click 不工作的权利。当我坐下来，我确定 owner.SourceControl 行， SourceControl 为空，我无法继续。现在我知道，这 ToolStripMenuItem 嵌套在一个又一个在我的的ContextMenuStrip ，但为什么是 SourceControl 财产suddently空我的的ContextMenuStrip ？

But my method for contextJumpToHeatmapStart_Click does not work right. When I get down to the line where I determine owner.SourceControl, the SourceControl is null and I cannot proceed. Now I know that this ToolStripMenuItem is nested under another one in my ContextMenuStrip, but why is the SourceControl property suddently null on my ContextMenuStrip?

我如何获得 SourceControl 嵌套 ToolStripMenuItem 为的ContextMenuStrip ？

推荐答案

我认为这是一个错误。

我试图爬上工具条父母的名单去了ContextStripMenu所有者，它的工作，但SourceControl属性总是空。

I tried to crawl up the list of toolstrip parents to get to the ContextStripMenu owner, which worked, but the SourceControl property was always null.

它看起来像常见的解决办法是设置控件的上下文菜单的打开：

It looks like the common work around is to set the control on the opening of the context menu:

private Control menuSource;

cms.Opening += cms_Opening;

void cms_Opening(object sender, CancelEventArgs e) {
  menuSource = ((ContextMenuStrip)sender).SourceControl;
}

那么你的code基本上变成这样：

Then your code basically turns into this:

DataGridView dgv = menuSource as DataGridView;
if (dgv != null) {
  // do work
}

这篇关于ContextMenuStrip.Owner属性空当检索从嵌套ToolStripMenuItem的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！