{"id":514,"date":"2011-09-09T09:16:27","date_gmt":"2011-09-09T07:16:27","guid":{"rendered":"http:\/\/hen.co.za\/blog\/?p=514"},"modified":"2011-09-09T09:17:10","modified_gmt":"2011-09-09T07:17:10","slug":"treeviewex-a-few-enhancements","status":"publish","type":"post","link":"https:\/\/hen.co.za\/blog\/2011\/09\/treeviewex-a-few-enhancements\/","title":{"rendered":"TreeViewEx – a few enhancements"},"content":{"rendered":"

Sometimes I wonder why some functionality that should be common is simply left out of general controls.. like the WinForms TreeView<\/em> (and ListView<\/em>) controls that don’t have specific events for the enter key pressed. I’ve been taught long ago to always provide functionality so keyboard events also can be used to navigate around applications – like when the mouse is unavailable, broken or not your first choice (like for disabled people). Yes, I know the controls have general events for key pressing but it requires some hectic coding each time to do something that should be simple.<\/p>\n

Anyway, adding it isn’t too difficult (but I still wished I didn’t have to do it each time I need to use it).<\/p>\n

public class<\/span> TreeViewEx : TreeView<\/span>
\n{<\/p>\n

public<\/span> TreeViewEx() : base<\/span>()
\n{<\/p>\n

DoubleBuffered = true<\/span>;<\/p>\n

}
\n public event MethodInvoker<\/span> EnterKeyPressed;
\n public event MethodInvoker<\/span> DeleteKeyPressed;
\n protected override void<\/span> OnKeyPress(KeyPressEventArgs<\/span> e)
\n{<\/p>\n

if<\/span> (e.KeyChar == ‘\\r’)<\/p>\n

if (EnterKeyPressed != null<\/span>)
\n{<\/p>\n

EnterKeyPressed();
\ne.Handled = true<\/span>;<\/p>\n

}<\/p>\n

base<\/span>.OnKeyPress(e);<\/p>\n

}<\/p>\n

protected override void<\/span> OnKeyDown(KeyEventArgs<\/span> e)
\n{<\/p>\n

if<\/span> (e.KeyCode == Keys<\/span>.Delete)<\/p>\n

if<\/span> (DeleteKeyPressed != null<\/span>)
\n{<\/p>\n

DeleteKeyPressed();
\ne.Handled = true<\/span>;<\/p>\n

}<\/p>\n

base<\/span>.OnKeyDown(e);<\/p>\n

}<\/p>\n

}<\/p><\/blockquote>\n

The code for the ListView<\/em> control is basically (exactly) the same.<\/p>\n","protected":false},"excerpt":{"rendered":"

Sometimes I wonder why some functionality that should be common is simply left out of general controls.. like the WinForms TreeView (and ListView) controls that don’t have specific events for the enter key pressed. I’ve been taught long ago to …<\/p>\n

Read more »<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[7,8,9,12,303,11,75,10],"class_list":["post-514","post","type-post","status-publish","format-standard","hentry","category-development","tag-net","tag-c","tag-code","tag-control","tag-development","tag-listview","tag-treeview","tag-winforms"],"_links":{"self":[{"href":"https:\/\/hen.co.za\/blog\/wp-json\/wp\/v2\/posts\/514","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hen.co.za\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hen.co.za\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hen.co.za\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hen.co.za\/blog\/wp-json\/wp\/v2\/comments?post=514"}],"version-history":[{"count":3,"href":"https:\/\/hen.co.za\/blog\/wp-json\/wp\/v2\/posts\/514\/revisions"}],"predecessor-version":[{"id":517,"href":"https:\/\/hen.co.za\/blog\/wp-json\/wp\/v2\/posts\/514\/revisions\/517"}],"wp:attachment":[{"href":"https:\/\/hen.co.za\/blog\/wp-json\/wp\/v2\/media?parent=514"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hen.co.za\/blog\/wp-json\/wp\/v2\/categories?post=514"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hen.co.za\/blog\/wp-json\/wp\/v2\/tags?post=514"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}