| Subject | Select multiple records in a grid |
| From | Mervyn Bick <invalid@invalid.invald> |
| Date | Wed, 19 Sep 2018 22:40:24 +0200 |
| Newsgroups | dbase.getting-started |
| Attachment(s) | test_multigridselect.wfm |
On 2018-09-19 6:31 PM, Kinsley wrote: > OK perhaps I need to ask a different question. If I want to allow a user to select multiple rows in a grid without having to add a new field to a dbfile how do I go about it? What is the best solution for this? I'm no expert in DBase coding so the simpler the solution the better if I am honest. Normally all one needs to do is set the grid's multiselect property true and then hold down the control key while clicking on a record in the grid. A problem is that the top record is always selected when the grid opens. If the user doesn't want to include this record in the selection it has to be deliberately de-selected by holding down the control key and then clicking on the record. The attached example emulates holding down the control key and clicking on the first record to de-select it when the grid opens. The user can then select the required records. If you uncomment the code in the onMouseOver and onMouseOut event handlers the user need not use the control key to select multiple records. This is, however, not standard practice so it may not be a good idea. Up to you. Mervyn. | |
if file('test_multiselect.dbf') // drop table test_multiselect endif if not file('test_multiselect.dbf') create table test_multiselect (id autoinc,data character(10)) use test_multiselect generate 10 use endif ** END HEADER -- do not remove this line // // Generated on 2014/02/18 // parameter bModal local f f = new test_multigridselectForm() if (bModal) f.mdi = false // ensure not MDI f.readModal() else f.open() endif class test_multigridselectForm of FORM with (this) onOpen = class::FORM_ONOPEN onClose = class::FORM_ONCLOSE height = 18.9091 left = 68.4286 top = 1.5909 width = 45.5714 text = "" endwith this.CHILDTEST1 = new QUERY() this.CHILDTEST1.parent = this with (this.CHILDTEST1) left = -0.2857 top = 0.0455 sql = 'select * from "test_multiselect.DBF"' active = true endwith this.GRID1 = new GRID(this) with (this.GRID1) onOpen = class::GRID1_ONOPEN onMouseOver = class::GRID1_ONMOUSEOVER onMouseOut = class::GRID1_ONMOUSEOUT dataLink = form.childtest1.rowset multiSelect = true height = 10.6364 left = 4.0 top = 2.8636 width = 36.5714 endwith this.PUSHBUTTON1 = new PUSHBUTTON(this) with (this.PUSHBUTTON1) onClick = class::PUSHBUTTON1_ONCLICK height = 1.7727 left = 15.1429 top = 14.9545 width = 15.2857 text = "Clear selection" endwith this.TEXTLABEL1 = new TEXTLABEL(this) with (this.TEXTLABEL1) height = 1.0 left = 16.1429 top = 0.8636 width = 12.2857 text = "Select records" endwith this.rowset = this.childtest1.rowset function GRID1_onMouseOut(flags, col, row) // class::setcontrolkey(0,1) //release control key return function GRID1_onMouseOver(flags, col, row) // class::setcontrolkey(1,0) //hold down contol key return function GRID1_onOpen class::deselectEntry() return function PUSHBUTTON1_onClick local aGrid aGrid = new array() aGrid = form.grid1.selected() for n = 1 to aGrid.size form.rowset.goto(aGrid[n]) class::deselectEntry() next form.rowset.first() class::deselectEntry() return function form_onClose class::setcontrolkey(0,1) //make quite sure control key is released return function form_onOpen #include winuser.h if type("SendMessage") # "FP" extern clong SendMessage(chandle,cuint,clong,clong) user32 ; from "SendMessageA" endif if type("GetKeyboardState") # "FP" extern CVOID GetKeyboardState(CPTR) User32 endif if type("SetKeyboardState") # "FP" extern CVOID SetKeyboardState(CPTR) User32 endif return function setcontrolkey(onoff,nstate) local keybuffer,state keybuffer = Space(256) GetKeyboardState(keybuffer) state=keybuffer.getbyte(vk_control) If onoff # 0 nstate=bitor(128,state) endif keybuffer.setbyte(vk_control,nstate) SetKeyboardState(keybuffer) return state function deselectEntry local point class::setcontrolkey(1,0) sendmessage(form.grid1.hwnd,wm_lbuttondown,9,0x220018) sendmessage(form.grid1.hwnd,wm_lbuttonup,9,0x220018) class::setcontrolkey(0,1) return endclass | |