{"id":18473,"date":"2009-04-23T10:00:00","date_gmt":"2009-04-23T10:00:00","guid":{"rendered":"https:\/\/blogs.msdn.microsoft.com\/oldnewthing\/2009\/04\/23\/why-are-there-two-values-for-psh_wizard97\/"},"modified":"2009-04-23T10:00:00","modified_gmt":"2009-04-23T10:00:00","slug":"why-are-there-two-values-for-psh_wizard97","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/oldnewthing\/20090423-00\/?p=18473","title":{"rendered":"Why are there two values for PSH_WIZARD97?"},"content":{"rendered":"

\nWelcome, Slashdot readers.\nRemember, this Web site is\n\nfor entertainment purposes only<\/A>.<\/I>\n<\/P>\n

\nIf you go cruising through the commctrl.h<\/CODE> header file,\nyou’ll find that there are two different definitions for\nPSH_WIZARD97<\/CODE>:\n

\n#if (_WIN32_IE >= 0x0400)\n…\n#if (_WIN32_IE < 0x0500)\n#define PSH_WIZARD97            0x00002000\n#else\n#define PSH_WIZARD97            0x01000000\n#endif\n…\n<\/PRE>\n
\nWhy are there two values for PSH_WIZARD97<\/CODE>?\n<\/P>\n
\nSet the wayback machine to 1997.\n(Note: Dates are approximate.)\nThe user interface design team studied how Windows 95\nwizards have been faring and have begun using what they’ve\nlearned to develop the next version of the wizard interface,\nwhich they have code-named “Wizard 97”.\nDevelopment in comctl32.dll<\/CODE>\nproceeds based their designs, what with exterior and interior pages,\nheaders and sub-headers, watermarks, all that jazz.\nMeanwhile, work on Internet Explorer 4 reaches the homestretch,\nand it’s a race to the finish line.\n<\/P>\n
\nInternet Explorer 4 wins the race and is ready to ship\nbefore the work on Wizard 97 is complete.\nWhat do you do?\nDo you say “Um, hi, Internet Explorer team.\nCould you slip your schedule by about half a year so we can finish\nour work on this new wizard design?”\nYeah, like the Internet Explorer team are going to say,\n“Oh, sure, no hurry, take your time. We’ll wait.\nIt’s not like we’re going to get ridiculed for being another six months\nlate.”\n<\/P>\n
\nAnd\n\nmonkeys might fly out of my butt<\/A>.\n<\/P>\n
\nOut the door it goes, with a Wizard 97 design that hadn’t\ngone through a full usability review.\nTo discourage programmers from using this half-finished wizard,\nput the sentence “Don’t use this flag” in the documentation.\nBoy, that was a close call.\n<\/P>\n
\nSince they already “missed the boat”, the urgency to complete\nthe work on Wizard 97 vanished.\nOne of the things that came up during the usability review was\nthat the full-page watermark wasn’t such a great idea after all.\nIt made the text hard to read,\nusers had difficulty figuring out what they should do,\nvarious problems like that.\nThe design for Wizard 97 changed;\nnow the watermark was just a small picture\nthat goes in the corner of the wizard.\nOf course, the changes weren’t just design changes;\nthere were also bug fixes.\nAll the work was done in time for Windows 2000, yippee.\n<\/P>\n
\nAnd then the compatibility bugs started coming in.\n<\/P>\n
\nWait, compatibility bugs?\nHow can there be compatibility bugs?\nNobody is using Wizard 97 yet; there’s nobody to be compatible with!\n<\/P>\n
\nWell, it turns out that programs were indeed using the\nPSH_WIZARD97<\/CODE> flag from Internet Explorer 4\nand expecting to get that old half-baked Wizard 97 design.\n(After some investigation, I believe we discovered that somebody\nsomewhere had told the MFC folks, “Hey, there’s this cool Wizard 97\nthing you should use. It’s pretty awesome.”\nThat someone was overcome with excitement and didn’t realize that\nthe work on Wizard 97 was not yet finished and that Wizard 97\nwas not yet ready for prime time.\nPeople who used MFC to write their programs then said,\n“Hey, look, MFC has support for this new type of wizard!”\nand started using it.)\n<\/P>\n
\nOh, great, how do you fix this?\n<\/P>\n
\nIt wasn’t pretty, but it had to be done.\n(The preferred first choice,\n\nusing a time machine<\/A>,\nwas unavailable.)\nThe fix was to have two types of Wizard 97;\nthere’s the “Internet Explorer 4 version” and the\n“Windows 2000 version”.\nOf course, nobody wants to officially admit that\nthe Internet Explorer 4 version exists, since during\nits brief lifetime, it was documented as “Don’t use me!”\nAll the changes that were made after Internet Explorer 4\nshipped had to be revisited.\nEach time there was a code change\n(either to support a new design or just to fix a bug),\na test against the wizard flavor had to be made,\nand the old behavior restored if the old flag was used.\n<\/P>\n
\nIf new code was added for the Windows 2000 version of\nWizard 97,\nwhether it be due to a design change or a bug fix,\nthen it had to be placed behind a check:\n<\/P>\n
\n    if (program asked for Windows 2000-style Wizard 97) {\n        \/\/ new behavior here\n    }\n<\/PRE>\n
\nConversely, if code was deleted, it had to be brought back\nwith a version check:\n<\/P>\n
\n    if (program asked for Internet Explorer 4-style Wizard 97) {\n        \/\/ old behavior here\n    }\n<\/PRE>\n
\nAnd if behavior changed, you need to have both versions:\n<\/P>\n
\n    if (program asked for Internet Explorer 4-style Wizard 97) {\n        \/\/ old behavior here\n    } else {\n        \/\/ new behavior here\n    }\n<\/PRE>\n
\nGiving the old and new Wizard 97 flags different values\nallows the property sheet wizard code to tell whether the\nprogram was designed for the\nbogus Internet Explorer 4 pre-release version of\nWizard 97 or the finished Windows 2000 version.\n<\/P><\/p>\n","protected":false},"excerpt":{"rendered":"
Welcome, Slashdot readers. Remember, this Web site is for entertainment purposes only. If you go cruising through the commctrl.h header file, you’ll find that there are two different definitions for PSH_WIZARD97: #if (_WIN32_IE >= 0x0400) … #if (_WIN32_IE < 0x0500) #define PSH_WIZARD97 0x00002000 #else #define PSH_WIZARD97 0x01000000 #endif … Why are there two values for […]<\/p>\n","protected":false},"author":1069,"featured_media":111744,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[2],"class_list":["post-18473","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-oldnewthing","tag-history"],"acf":[],"blog_post_summary":"
Welcome, Slashdot readers. Remember, this Web site is for entertainment purposes only. If you go cruising through the commctrl.h header file, you’ll find that there are two different definitions for PSH_WIZARD97: #if (_WIN32_IE >= 0x0400) … #if (_WIN32_IE < 0x0500) #define PSH_WIZARD97 0x00002000 #else #define PSH_WIZARD97 0x01000000 #endif … Why are there two values for […]<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts\/18473","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/users\/1069"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/comments?post=18473"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts\/18473\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/media\/111744"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/media?parent=18473"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/categories?post=18473"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/tags?post=18473"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}