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Visual Basic Form | 1992-01-05 | 13.7 KB | 298 lines

Form1 Linking/SmartFill Demo Form1 Text1 Command1 List1 Command2 Demo Info Command3 Cancel txtEntry_Change String2Find! TxtEntry wIndex LstFindEntry Result SendMessage GetFocus LB_SELECTSTRINGq cmdClear_Click^ DropCombo AutoRedraw start LB_RESETCONTENT CurrentXj CmdClear CurrentY Height Totalz cmdOk cmdClearVB_Click whiel ListCount cmdLoad_ClickL AddStr cmdOK_Click LstFindEntry_ClickS SPEEDTYPE- SelStart List' SelLength| Cbo_Last` SelectionStart txtEntry_KeyPress KeyAscii TxtLen txtEntry_KeyUp KeyCode Shift DontSearch" FALSE txtEntry_KeyDown ListIndex Index LstFindIndex Lindexx STARTSPEEDTYPING Lscroll TxtEntrly1 LoadSampleDataV Form_Click @ Form_Load window_ state LoadSomeSampleData WindowState Txt_Text1_Change" Txt_Text1. Txt_Text1_KeyDownB Lst_Link1N Lst_Link1_Click Cmd_Command1_Click SearchString StartSearch; TxtText1_Change TxtText1 TxtText1_KeyDowni LstLink1` LstLink1_Click List1 List1_Click3 Text1 Text1_Change Text1_KeyDownd Command1_Click wParm lparamU NewListIndex StartSmartFill NORMAL KEY_BACK KEY_DELETE? KEY_PGUPI KEY_PGDN KEY_UP KEY_DOWN Text1_KeyUp Command2_Click Microsoft there product give[ users Command3_Click MB_YESNO2 ID_YESD MB_YESCANCEL IDYES andIf MB_OKCANCEL AText1 sTemp lTemp characters SmartFill typed enough MB_ICONINFORMATION Title: LINKDEMO.FRM Version: 1.0 Project: LINKDEMO.MAK Description: Demonstration of Linked Text/ListBoxes and SmartFill Demo ' Author: Jack Presley Created: Jan 4, 1992 Last Revision: Jan 4, 1992 23:00 Click on "Demo Info" for more information about this demonstration. API Function Declarations.n GetFocus returns hWnd% for the control with the current focus. VB's hWnd% only returns a value for forms, not controls.d This function does all the work of selecting thet matching element in our linked list box. It will do much more, such as clear a listbox with one call. SeeS the January 1992 "Inside Visual Basic" journal forf more details. Change this value to determine when to start filling in text box with data from list box. If the value is 2, and a link exists, when the user types the 3rd character the remaining characters will be filled in. LoadSampleData Just some junk mail to put in our list box... Ralph" Janet" Lloyd" Thomas Andrew Anderson Anderman Beeson Martin McAngus" Caroline Joseph Steven Robert Sarah" Cindy" Karen" Dennis Gladys Form_Load This is explained in Text1_Change List1_Click This routine places the item which was clicked upon into the Text box. This in turn causes a Text1_Changen event to occur, which resets the focus to the linkedk text box. Text1_Change If certain keys are pressed we do not want to searchr the linked list box. 'DontSearch' is set in thet Text1_KeyUp procedure. See it for more info. Can't pass Text1.Text "ByVal" so assign it to a normal string variable... Save our position in the text box This is where our SmartFill will begin... Start our search at the beginning...w Set the focus to the linked list so we can geth it's "hWnd%" value with GetFocust Make the call...t If we found a match and we want to search and we have typed enough characters to start SmartFill... restore the insertion point and selection...t we had to change it to the list box, remember?! Command1_Click You did not select anyone. Link Demonstration Nothing in the text box, leave... We've hit the list Test for a match... You have selected for updating. Link Demonstration Exit now to avoid next test...s The selection has failed both previous tests, must be a new guy. Do we add him/her or move on? is not in the list. Would you like to add them to the list?" Link Demonstration Add the item... Highlight the new guy in the text and list boxes... Let them start over Text1_KeyDown This routine allows the user to scroll through the list box while the focus is in the text box. This simulates a link. This routine needs to be in the KeyDown vs. KeyUp to allowl the user to hold a key down and scroll. You may experiment and replace the work KeyDown with KeyUp in the Sub statemente above and watch what happens when you press and hold the up or down arrow, or PgUp/PgDn.D If there is nothing in the list, leave... A temp variable because I'm a lazy typer... Determine how much to scroll with a PgUp or PgDnh minimum will use 1/10 of the total... If the user presses the backspace or delete key, we don't want' to search for a match in our linked listbox on this pass. If we did the search we would find a match and probably replace thea text he just deleted with the same text. The user could keep typing, but could never back up or erase the selected text. Yout may change the TRUE (below) to FALSE to see what happens. These lines do the scrolling in the list box. The "KeyCode = 0" statement, effectively erases the keystroke so the text box is notn affected. Don't Change anything Make sure the new ListIndex value is legal... Set the new value...s Command2_Click Define All messages first for a little faster response... Linked Text/List Box and SmartFill Demonstration" Jack Presley" Version 1 January 4, 1992 This program demonstrates two effective tools which you may use in your Visual Basic Applications. The first is the Linked Text " and List box. Although I had previously accomplished this " without any API calls by trapping keys, the recent article " 'Creating a new control--the Combo Dropdown List box' in 'Inside " Visual Basic' Vol. 2 No. 1 (January 1992) provided me with a " better and faster way to make the link. As the user types in the text box, a 'greater than or equal to' search is performed on the linked list box using whatever has been typed into the text box as the key. When the user presses OK to confirm his choice, a simple comparison of the Text box text and the Listbox index text will tell you if the text is in the list box or not. There's more... I use this 'modified' control regularly in my database " applications. I put the key field in a linked text/list box. " When the user makes a selection in this control I can either " update the form with that records data or query the user if they " would like to add this as a new record. I've got to admit that the side affect I like the most is NO SCROLL controls are on my forms! The linked list/text box IS the scroll bar. On small forms I update the form with every Link_Change. This makes " scrolling a little slower, but lets the user browse through the records. On large forms I update the form with Link_DoubleClick " or Command1_Click, unless the user selects a browse option. This is just one example of the way I put Linked Text/List boxes to " use. Click OK for information on SpeedFill... " SpeedFill is a real time saver. It uses the match found in the Linked List box to 'fill in' the remainder of the selection being made in the Linked Text box. You may change the number of keystrokes required to 'kick in' SpeedFill. Normally you don't want to start it until after the second keystroke or so. The way SpeedFill works is really pretty simple. When a key is pressed the program records how may characters are in the Text " box text. If a match is found in the Linked list box, that text " is assigned to the Text box text. Here's the magic: Assign the previous text length to the SelStart property and SelLength to " the length of the new Text box text. Everything in the new SUGGESTED text that was NOT typed by the user is highlighted. " Since Windows replaces highlighted text with the next keystroke, " the user can simply keep typing until a match is made or the text is complete. I make this an option in all my apps." If you use the Linked Text/List box, SpeedFill is an easy option to give your users. This snippet of code and unsolicited advice is free. Please feel " free to use it as you wish. BUT if you decide to upload it with " *ANY* changes, PLEASE, PLEASE remove my name and address from all the modules. Thanks, and good luck. " Jack Presley CIS: 70700,166 BIX: JackPresley Presley Computing" Route 4, Box 4171 Boerne, TX 78006 (512) 755-9018 (512) 977-0650 (FAX) I'm rarely on Bix and my presence on Compuserve is somewhat inconsistent. If you really need to get in touch, call or fax." P.S. I will have a new address and phone numbers February 1, 1992." Link Demonstration Link Demonstration SpeedFill" Link Demonstration Command3_Click Hopefully this isn't the end. If you improve these procedures, please let me and others know about it. Everyone needs feedback; good or bad. Thanks, Jack Presley