Locate a record in a TDBAdvGrid with PageMode off - delphi

I am desperately trying to do a Locate on a record whose PK is associated to Column 0 in a TDBAdvGrid. The TMS Component Pack version I have is 6.8.something.
I am using it in a Win7x64 with Delphi XE 1.
PageMode is turned off because I will need sorting and grouping at the client level(no backend db for now, only client datasets in offline mode).
My code for the locate is like this:
procedure TMainFrm.EditAction;
var ItemID : Integer;
ItemIDStr: String;
begin
// With PageMode set to false(which we need), the dataset is not synchronized.
//ItemID := GetActionGrid.Columns[ 0 ].Field.AsInteger;
ItemIDStr := GetActionGrid.Cells[ 0,GetActionGrid.SelectedRow[ 0 ] ];
ItemID := StrToIntDef( ItemIDStr ,-1 );
// GetActionGrid.Fields[ 0 ].AsInteger;
If DMMain.CLNActions.Locate( 'ITEM_ID',ItemID,[] ) Then
CreateApplicationForm( TActionFrm, True );
end;
But it does not work because the ItemIDStr always returns an empty string.
I am really short of ideas now.
Suggestions?
Thank you!

function TFrameDBGrid1.GrFindValInCol(FldName, FldVal : String) : boolean; //search value in a certain column of the grid
var
StartCell:TPoint;
FindParams: TFindParams;
rv:TPoint;
CurrCol: integer;
I: Integer;
const CResultInvalidInt=-1;
begin
Result := false;
StartCell.x := CResultInvalidInt;
StartCell.y := CResultInvalidInt;
CurrCol := GetColumnIndexOfField(FldName);
grdGlobal.FindCol := CurrCol;
FindParams := [fnMatchRegular, fnFindInPresetCol];
rv:=grdGlobal.Find(StartCell, FldVal, FindParams);
Result:= (rv.x <> CResultInvalidInt) and (rv.y <> CResultInvalidInt);
if Result then
if grdGlobal.Row <> rv.y then
grdGlobal.Row := rv.y;
end;

Related

ADO insert a record into access DB using delphi

Am learning how to use insert into statements and, with my access database, am trying to insert a single record. The table I'm inserting a new record into has three fields: StockID (AutoN), Description (Text), Cost (Number). I've looked at previous posts but the posted solutions seem to go beyond my basic level of Insert Into...which is what I'm interested in. Anyway, here is my code...
adoQuery1.Active := true;
adoQuery1.SQL.Clear;
adoQuery1.SQL.Add('INSERT INTO Stock (StockID,Description,Cost) VALUES (4,Cheese,5)');
adoQuery1.open;
adoQuery1.Close;
It compiles fine, but when press a command button to invoke the above, I get the following message:
'ADOQuery1: "Missing SQL property".'
what am I doing wrong?
Thanks, Abelisto. Your last post looks complex indeed...but I did my own little version since your last solution got me up and running. It works so I'm very chuffed. Am now going to focus on DELETE FROM using combobox (for field selection) and user value. Here was my solution I got working... ;)
x:=strtoint(txtStockID.Text);
y:=txtDescription.Text;
z:=strtoCurr(txtCost.Text);
adoQuery1.SQL.Clear;
adoQuery1.SQL.Add('INSERT INTO tblStock (StockID,Description,Cost)');
adoQuery1.SQL.Add('VALUES (:StockID,:Description,:Cost)'); // ':StockID' denotes a parameter
adoQuery1.Parameters.ParamByName('StockID').Value:= x;
adoQuery1.Parameters.ParamByName('Description').Value:= y;
adoQuery1.Parameters.ParamByName('Cost').Value:= z;
adoQuery1.ExecSQL;
adoQuery1.Close;
Using parameters is more efficient then constant SQL statements.
Additional to my comments here is some useful functions which I using frequently to call SQL statements with parameters (Maybe it will be useful for you too):
function TCore.ExecQuery(const ASQL: String; const AParamNames: array of string;
const AParamValues: array of Variant): Integer;
var
q: TADOQuery;
i: Integer;
begin
if Length(AParamNames) <> Length(AParamValues) then
raise Exception.Create('There are different number of parameter names and values.');
q := GetQuery(ASQL) as TADOQuery;
try
for i := Low(AParamNames) to High(AParamNames) do
SetParamValue(q, AParamNames[i], AParamValues[i]);
q.ExecSQL;
Result := q.RowsAffected;
finally
q.Free;
end;
end;
function TCore.GetQuery(const ASQL: String): TDataSet;
begin
Result := TADOQuery.Create(Self);
(Result as TADOQuery).CommandTimeout := 0;
(Result as TADOQuery).Connection := Connection;
(Result as TADOQuery).SQL.Text := ASQL;
end;
procedure TCore.SetParamValue(AQuery: TDataSet; const AName: string; const AValue: Variant);
var
i: Integer;
q: TADOQuery;
begin
q := AQuery as TADOQuery;
for i := 0 to q.Parameters.Count - 1 do
if AnsiSameText(AName, q.Parameters[i].Name) then
begin
case VarType(AValue) of
varString, varUString:
q.Parameters[i].DataType := ftString;
varInteger:
q.Parameters[i].DataType := ftInteger;
varInt64:
q.Parameters[i].DataType := ftLargeint;
end;
q.Parameters[i].Value := AValue;
end;
end;
And usage example in your case:
Core.ExecQuery(
'INSERT INTO Stock (StockID, Description, Cost) VALUES (:PStockID, :PDescription, :PCost)',
['PStockID', 'PDescription', 'PCost'],
[4, 'Cheese', 5]);

Updating field in cxGrid acting strange

I have a function to update a cxGrid made with help from answers to Loop through records on a cxgrid and update a field/column
But it is sometimes acting a bit strange. If I open the form with the cxGrid and click the columnheader without doing anything else, the records are updateted OK. But if the 'selectorbar' is moved away from the top, the record marked is not updated.
I am sure it is a property that needs to be changed, but which one.
The variable fSelected is set to False at FormShow and is ther so that the user can unselect records as well.
procedure TfrmContactsSelect.colContactSelectedHeaderClick(Sender: TObject);
var
i: Integer;
Index: Integer;
BookMark : TBookMark;
Contact: variant;
begin
if fMulti = True then
begin
Screen.Cursor := crHourGlass;
fSelected := not fSelected;
BookMark := qryContacts.GetBookmark;
qryContacts.DisableControls;
try
for i := 0 to grdContactsView1.DataController.FilteredRecordCount - 1 do
begin
Index := grdContactsView1.DataController.FilteredRecordIndex[i];
Contact := grdContactsView1.DataController.Values[Index, 4];
if grdContactsView1.DataController.LocateByKey(Contact) then
begin
qryContacts.Edit;
qryContacts.FieldByName('fldcontact_selected').AsBoolean := fSelected;
qryContacts.Post;
end;
end;
finally
qryContacts.EnableControls;
qryContacts.GotoBookmark(BookMark);
qryContacts.FreeBookmark(BookMark);
end;
Screen.Cursor := crDefault;
end;
end;
Delphi XE7, DevExpress 14.2.2, UniDAC 5.5.12 for DB access
Comment:
I have ended up with the following solution based on the answer and input from MartynA
procedure TfrmContactsSelect.colContactSelectedHeaderClick(Sender: TObject);
var
i: Integer;
Index: Integer;
MarkedRecord: variant;
CurrentRecord: variant;
begin
if fMulti = True then
begin
Screen.Cursor := crHourGlass;
fSelected := not fSelected;
Index := grdContactsView1.DataController.FocusedRecordIndex;
MarkedRecord := grdContactsView1.DataController.Values[Index, colContactGuid.ID];
try
for i := 0 to grdContactsView1.DataController.FilteredRecordCount - 1 do
begin
Index := grdContactsView1.DataController.FilteredRecordIndex[i];
CurrentRecord := grdContactsView1.DataController.Values[Index, colContactGuid.ID];
if grdContactsView1.DataController.LocateByKey(CurrentRecord) then
begin
grdContactsView1.DataController.Edit;
grdContactsView1.DataController.SetEditValue(colContactSelected.ID, fSelected, evsText);
grdContactsView1.DataController.Post;
end;
end;
finally
grdContactsView1.DataController.LocateByKey(MarkedRecord);
end;
Screen.Cursor := crDefault;
end;
end;
I can reproduce your problem using the sample project I posted in my answer to your other q.
Try this: Add a TMemo to your form, and inside the 'if grdContactsView1.DataController.LocateByKey(Contact) then' block, write the value of a row-unique datafield and the Selected datafield value to the memo.
Then, what I get when some row other than the top row is selected is that one row is listed twice in the memo, with Selected both false and true, and one of the rows in the filter isn't listed at all, which I think accounts for the behaviour you're seeing. If I then comment out the .Edit .. .Post lines, it correctly lists all the rows in the filter.
So evidently doing the Selected field changes inside a block which iterated the FilteredRecordIndex property of the DBTableView is what's causing the problem.
Personally, I find that it goes a bit against the grain to modify dataset rows in code via a DB-aware control (because you usually end up fighting the DB-awareness of the control), but in this case, it's straightforward to do the processing via the DBTableView of the cxGrid.
procedure TForm1.ProcessFilteredRecords;
var
PrevV,
V : Variant;
i,
Index: Integer;
S : String;
begin
// First, pick up a reference to the current record
// so that we can return to it afterwards
Index := cxGrid1DBTableView1.DataController.FocusedRecordIndex;
PrevV := cxGrid1DBTableView1.DataController.Values[Index, 0];
try
for i := 0 to cxGrid1DBTableView1.DataController.FilteredRecordCount - 1 do begin
Index := cxGrid1DBTableView1.DataController.FilteredRecordIndex[i];
V := cxGrid1DBTableView1.DataController.Values[Index, 0];
if cxGrid1DBTableView1.DataController.LocateByKey(V) then begin
cxGrid1DBTableView1.DataController.Edit;
// 2 is the index of my Selected column in the grid
if cxGrid1DBTableView1.DataController.SetEditValue(2, True, evsText) then
Caption := 'OK'
else
Caption := 'Failed';
cxGrid1DBTableView1.DataController.Post;
end;
end;
finally
if cxGrid1DBTableView1.DataController.LocateByKey(PrevV) then
Caption := 'OK'
else
Caption := 'Failed';
end;
end;
Another way to avoid the problem is to change the Selected states in two steps:
Iterate the FilteredRecordIndex to build a list of rows to change - in your case this would be a list of guids
Then, iterate the list of rows and update their Selected states.
Code:
procedure TForm1.ProcessFilteredRecords;
var
V : Variant;
i,
Index: Integer;
BM : TBookMark;
S : String;
TL : TStringList;
begin
Memo1.Lines.Clear;
TL := TStringList.Create;
try
for i := 0 to cxGrid1DBTableView1.DataController.FilteredRecordCount - 1 do begin
Index := cxGrid1DBTableView1.DataController.FilteredRecordIndex[i];
V := cxGrid1DBTableView1.DataController.Values[Index, 0];
if cxGrid1DBTableView1.DataController.LocateByKey(V) then begin
if CDS1.FieldByName('Selected').AsBoolean then
S := 'True'
else
S := 'False';
S := CDS1.FieldByName('Name').AsString + ' ' + S;
Memo1.Lines.Add(S);
TL.Add(CDS1.FieldByName('Guid').AsString);
end;
end;
try
BM := CDS1.GetBookMark;
CDS1.DisableControls;
for i := 0 to TL.Count - 1 do begin
if CDS1.Locate('guid', TL[i], []) then begin
CDS1.Edit;
CDS1.FieldByName('Selected').AsBoolean := True;
CDS1.Post;
end
end;
finally
CDS1.EnableControls;
CDS1.GotoBookmark(BM);
CDS1.FreeBookmark(BM);
end;
finally
TL.Free;
end;
end;
Like you, I was expecting that changing a property or two of the cxGrid might avoid the problem without any code, but I haven't been able to find anything which does.

Create a fkInternalCalc field on TSQLQuery

The following Delphi function can be used to add a fkInternalCalc to a TClientDataset.
This is useful because I can store some information for each record, make calculation or store temporary flag.
The same code does not work in Lazarus, it stops on DataSet.FieldDefs.Update.
Are there means to achieve the same functionality?
Remember that one could change database fields and apply the changes made.
A working Delphi code using the function is:
AddDummyField(qry,TIntegerField,'PROCESS_ACTION');
qry.Open;
...
function AddDummyField(Dataset:TDataset;fieldClass:TFieldClass;fieldName:string;size:integer):TField;
var
i: Integer;
begin
if Dataset.FieldDefs.Count = 0 then
begin
DataSet.FieldDefs.Update;
for i := 0 to DataSet.FieldDefs.Count - 1 do
DataSet.FieldDefs[i].CreateField(DataSet);
end;
Result := Dataset.FindField(fieldName);
if Result <> nil then
exit;
Result := fieldClass.Create(Dataset);
Result.FieldName := fieldName;
Result.FieldKind := fkInternalCalc;
Result.DataSet := Dataset;
if size>0 then
Result.Size := size;
end;
You have to open the dataset before.
...
DataSet.Open;
DataSet.FieldDefs.Update;
DataSet.Close;
for i := 0 to DataSet.FieldDefs.Count - 1 do
DataSet.FieldDefs[i].CreateField(DataSet);
...

Save Dbgrid Column Width Values to Ini and Reread them

I have Inherited form and a Ehlib dbgrid on it for selecting-listing records... The form is ready made for a lot of buttons and im using this form with different queries.
Like this...
If Dm.QrTmp.Active then Dm.QrTmp.Active:=False;
Dm.QrTmp.SQL.Clear;
Dm.QrTmp.SQL.Add(' SELECT ');
Dm.QrTmp.SQL.Add(' ch.cari_RECno AS KayitNo ');
Dm.QrTmp.SQL.Add(' FROM CARI_HESAPLAR ch ');
if FrmTmp=nil then FrmTmp:=TFrmTmp.Create(Self);
FrmTmp.StatusBar.Hide;
Dm.QrTmp.Open;
FrmTmp.DbGrid.DataSource:=Dm.DsQrTmp;
This query is cutted down but i have of course use a lot of fields. And Queries changes alot of time in the application.
The problem is column width. Manager wants to set column widths and restore them again. Actually my grid component supports save - restore column properties but as you can see my usage i m not using static columns. also i dont want to use xgrid.columns[0].width percent by percent.
Im using a ini in may app.
I want to add new section on it and named "Gridwidth"...
[Gridname]
Colwidths=x,y,z (where they are width values)
I'm now coding this line by line.
My write procedure is like this.
With dbgridx do
begin
For i:=0 to columns.count-1
begin
widthstr:=widthstr+Column[i].width+',';
end;
end;
Widthstr will be "15,23,45,67" etc...
But i want to know if this is good solution and if somebody know a better way and has some good code.
This should do it:
uses
IniFiles;
const
SETTINGS_FILE = 'Edijus\Settings.ini';
procedure TForm1.LoadDBGridColumnsWidth(const ADBGrid: TDBGrid);
var
_MemIniU: TMemIniFile;
_SettingsPath: string;
i, j: integer;
_ParentClass: TWinControl;
begin
_SettingsPath := GetHomePath + PathDelim + SETTINGS_FILE;
if (not Assigned(ADBGrid)) or (not Assigned(ADBGrid.DataSource)) or
(not Assigned(ADBGrid.DataSource.DataSet)) then
Exit;
_MemIniU := TMemIniFile.Create(_SettingsPath, TEncoding.UTF8);
try
_ParentClass := ADBGrid.Parent;
while not(_ParentClass is TForm) do
_ParentClass := _ParentClass.Parent;
for i := 0 to Pred(ADBGrid.DataSource.DataSet.Fields.Count) do
for j := 0 to Pred(ADBGrid.Columns.Count) do
begin
if (ADBGrid.DataSource.DataSet.Fields[i].FieldName = ADBGrid.Columns[j]
.FieldName) then
ADBGrid.Columns[j].Width :=
_MemIniU.ReadInteger(_ParentClass.Name + '_' + ADBGrid.Name,
ADBGrid.Columns[j].FieldName, 64);
end;
finally
FreeAndNil(_MemIniU);
end;
end;
procedure TForm1.SaveDBGridColumnsWidth(const ADBGrid: TDBGrid);
var
_MemIniU: TMemIniFile;
_SettingsPath: string;
i: integer;
_ParentClass: TWinControl;
begin
_SettingsPath := GetHomePath + PathDelim + SETTINGS_FILE;
if (not Assigned(ADBGrid)) or
(not ForceDirectories(ExtractFilePath(_SettingsPath))) then
Exit;
_MemIniU := TMemIniFile.Create(_SettingsPath, TEncoding.UTF8);
try
_ParentClass := ADBGrid.Parent;
while not(_ParentClass is TForm) do
_ParentClass := _ParentClass.Parent;
for i := 0 to Pred(ADBGrid.Columns.Count) do
if (ADBGrid.Columns[i].FieldName <> '') then
_MemIniU.WriteInteger(_ParentClass.Name + '_' + ADBGrid.Name,
ADBGrid.Columns[i].FieldName, ADBGrid.Columns[i].Width);
_MemIniU.UpdateFile;
finally
FreeAndNil(_MemIniU);
end;
end;

How to do incremental search in delphi FM2?

Hi i am having a problem with incremental search in delphi.
I Have looked at this http://delphi.about.com/od/vclusing/a/lb_incremental.htm
But this doesn't work in firemonkey so i came up with this :
for I := 0 to lstbxMapList.Items.Count-1 do
begin
if lstbxMapList.Items[i] = edtSearch.Text then
begin
lstbxMapList.ItemByIndex(i).Visible := True;
end;
if lstbxMapList.Items[I] <> edtSearch.Text then
begin
lstbxMapList.ItemByIndex(i).Visible := False;
end;
end;
When i use this the listbox is just blank.
You're hiding every item that doesn't exactly match edtSearch.Text. Try this instead (tested in XE3):
// Add StrUtils to your uses clause for `StartsText`
uses
StrUtils;
procedure TForm1.edtSearchChange(Sender: TObject);
var
i: Integer;
NewIndex: Integer;
begin
NewIndex := -1;
for i := 0 to lstBxMapList.Items.Count - 1 do
if StartsText(Edit1.Text, lstBxMapList.Items[i]) then
begin
NewIndex := i;
Break;
end;
// Set to matching index if found, or -1 if not
lstBxMapList.ItemIndex := NewIndex;
end;
Following from Kens answer, if you want to hide items as per your question, just set the Visible property but note that since the expression of an if statement returns a boolean and Visible is a boolean property it's possible to greatly simplify things. Note also that I've also used ContainsText which will match the string anywhere in the item text:
procedure TForm1.edtSearchChange(Sender: TObject);
var
Item: TListBoxItem;
begin
for Item in lstbxMapList.ListItems do
Item.Visible := ContainsText(Item.Text.ToLower, Edit1.Text.ToLower);
end;

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