Creating buttons from database table on runtime in Delphi - delphi

I want to create buttons from Database on runtime.
For example I have a table lets say users.
I need to create as many buttons as the user table contains.
The following code does that. But I have a problem,
it gives me the last button only or it puts all buttons on top of other and I see only last button.
I need to get the buttons one next to other.
procedure TForm1.Button2Click(Sender: TObject);
var
Bt: TButton;
i: Integer;
begin
Query1.First;
while not Query1.Eof do
begin
i:=0;
Bt := TButton.Create(Self);
Bt.Caption := Query1.Fields[0].AsString;
Bt.Parent := Self;
Bt.Height := 23;
Bt.Width := 100;
Bt.Left := 10;
Bt.Top := 10 + i * 25;
i:= i+1;
Query1.Next;
end;
end;
what should I change or add?

You reset the i counter with every loop iteration. Initialize it once before you enter the loop:
procedure TForm1.Button2Click(Sender: TObject);
var
i: Integer;
Bt: TButton;
begin
Query1.First;
i := 0; // initialize the counter before you enter the loop
while not Query1.Eof do
begin
Bt := TButton.Create(Self);
Bt.Caption := Query1.Fields[0].AsString;
Bt.Parent := Self;
Bt.Height := 23;
Bt.Width := 100;
Bt.Left := 10;
Bt.Top := 10 + i * 25;
i := i + 1;
Query1.Next;
end;
end;

Related

Creating custom button in Delphi with different actions [closed]

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I am creating a custom component, a button-switch like this :
In my "form activate" function, I wrote a for loop in which I call 3 times the button function with a different position parameter like : SwitchButton(30); where 30 is the top position.
What I want to do is assign at these 3 buttons different actions, here some code.
Code for button creation :
procedure TFMain.SwitchButton(posPulsante: Integer);
var
i: Integer;
posDescrizionePulsante: Integer;
strDescrizione: String;
begin
posDescrizionePulsante := 32;
lastPressed := 1;
Pulsante := TPanel.Create(FMain);
BordoPulsante := TShape.Create(self);
LevaPulsante := TPanel.Create(self);
DescrizionePulsante := TLabel.Create(self);
//Proprietà Descrizione
with DescrizionePulsante do
begin
Parent := PComandi;
Top := posDescrizionePulsante;
Left := 100;
Caption := 'Visualizza finestra utenti';
Font.Name := 'Tahoma';
Font.Size := 12;
Font.Style := [fsBold];
Font.Color := clWhite;
end;
//Proprietà Pulsante
with Pulsante do
begin
Parent := PComandi;
ParentColor := false;
ParentBackground := false;
BevelOuter := bvNone;
Color := clWhite;
Width := 57;
Height := 25;
Top := posPulsante;
Left := 20;
Visible := true;
end;
//Proprietà Bordo
with BordoPulsante do
begin
Parent := Pulsante;
Align := alClient;
Brush.Style := bsClear;
Brush.Color := RGB(122,136,201);
Pen.Color := clWhite;
Pen.Style := psSolid;
Pen.Width := 3;
end;
//Proprietà Leva
with LevaPulsante do
begin
Parent := Pulsante;
ParentBackground := false;
ParentColor := false;
BevelOuter := bvNone;
Color := clWhite;
Cursor := crHandPoint;
Width := 23;
Height := 13;
Top := 6;
Left := 28;
LevaPulsante.OnClick := SwitchState;
end;
end;
Code for creating Button object :
procedure TFMain.FormActivate(Sender: TObject);
var
i: Integer;
posPulsante: Integer;
begin
posPulsante := 30;
for i := 1 to 3 do
begin
SwitchButton(posPulsante);
posPulsante := posPulsante + 50;
end;
end;
Would be nice to have some : if SwitchButton 1 is clicked then do something. if SwitchButton 2 is clicked then do something else.
I think this is an acceptable use of the Tag property. You can specify some number, for example the index of the for loop, in each of the panels:
procedure TFMain.FormActivate(Sender: TObject);
var
i: Integer;
posPulsante: Integer;
begin
posPulsante := 30;
for i := 1 to 3 do
begin
SwitchButton(posPulsante, i {For example, add the tag as extra parameter});
posPulsante := posPulsante + 50;
end;
end;
And then set that tag in the button, here using the added parameter indexPulsante.
procedure TFMain.SwitchButton(posPulsante: Integer; indexPulsante: Integer);
var
i: Integer;
posDescrizionePulsante: Integer;
strDescrizione: String;
begin
...
LevaPulsante.Tag := indexPulsante;
end;
And then, in the event handler (which I think you called SwitchState), you'll have the Sender, which is the control that was clicked (the panel, in your case).
procedure TFMain.SwitchState(Sender: TObject);
begin
case (Sender as TComponent).Tag of
1: ShowMessage('You clicked the first. Do something.')
2: ShowMessage('Do something else.')
else
ShowMessage('You clicked another button than 1 or 2');
end;
end;
NB: Tag is introduced in TComponent and therefore also available in TPanel. In the code above I only typecast to TComponent, because it doesn't matter that it's a panel to get the tag, but if you want to use other properties, a more specific cast may be needed. I like to keep the cast generic, to make it easier to make changes like switching to another type than TPanel, for instance when you actually gonna make a component out of this (inherited from TCustomControl?), or use a third party component.

DBGRID with Row Height variable

I would like to show in a DBGRID as follows:
Imagine "Grid" as follows:
ID - DESCRIPTION
1 - Line 1 of the grid
2 - Line 2 of the grid
3 - Line 3 of the grid
Now, suppose the size of the DESCRIPTION column is changed and no longer appear the words "GRID";
I would like to stay as well DBGRID
ID - DESCRIPTION
1 - Line 1 of the
grid
2 - Line 2 of the
grid
3 - Line 3 of the
grid
is there any possibility that ??
Not what you're asking, but might help... I once used this code to show complete Memo fields in the standard DBGrid:
TMyForm = class(TForm)
...
private
FormMemoRect: TRect;
MemoGrid: TDBGrid;
BMemo: TBitBtn;
...
Procedure TMyForm.FormMemoDeactivate(Sender: TObject);
Begin
(Sender As TForm).Close;
Sender.Free;
End;
Procedure TMyForm.BMemoClick(Sender: TObject);
Var FormMemo: TForm;
Begin
MemoGrid.SetFocus;
FormMemo := TForm.Create(Self);
With TMemo.Create(FormMemo) Do Begin
Parent := FormMemo;
Align := alClient;
ReadOnly := True;
WordWrap := True;
ScrollBars := ssVertical;
Lines.Text := MemoGrid.DataSource.DataSet.Fields[TComponent(Sender).Tag].AsString;
End;
With FormMemo Do Begin
OnDeactivate := FormMemoDeactivate;
Left := FormMemoRect.Left;
Top := FormMemoRect.Top;
Width := Max(FormMemoRect.Right - FormMemoRect.Left, 300);
Height := FormMemoRect.Bottom - FormMemoRect.Top;
BorderStyle := bsNone;
Show;
End;
End;
Procedure TMyForm.GrdMemoDrawColumnCell(Sender: TObject; Const Rect: TRect; DataCol: Integer; Column: TColumn; State: TGridDrawState);
Begin
If (gdFocused In State) Then Begin
If Column.Field.DataType In [ftBlob, ftMemo] Then Begin
{Desenha botão para visualização do Memo}
FormMemoRect.Left := TWinControl(Sender).ClientToScreen(Rect.TopLeft).X;
FormMemoRect.Right := TWinControl(Sender).ClientToScreen(Rect.BottomRight).X;
FormMemoRect.Top := TWinControl(Sender).ClientToScreen(Rect.BottomRight).Y;
FormMemoRect.Bottom := FormMemoRect.Top + 100;
If Not Assigned(BMemo) Then
BMemo := TBitBtn.Create(Self);
BMemo.Parent := TWinControl(Sender).Parent;
BMemo.Width := 16;
BMemo.Height := 16;
BMemo.Caption := '...';
BMemo.OnClick := BMemoClick;
BMemo.Tag := Column.Field.Index;
BMemo.Left := TWinControl(Sender).Left + Rect.Right - BMemo.Width + 1;
BMemo.Top := TWinControl(Sender).Top + Rect.Top + 2;
MemoGrid := TDBGrid(Sender);
End
Else
FreeAndNil(BMemo);
End;
End;
For Blob/Memo Fields, you may also find it useful to do some custom GetText to show something directly in the Grid:
Procedure TMyForm.DataSetMemoGetText(Sender: TField; var Text: String; DisplayText: Boolean);
Begin
Text := Copy(Sender.AsString, 1, 50);
If Text <> Sender.AsString Then
Text := Text + '...';
End;
This is how the result looks like.
PS: Sorry for non-standard code style.

Get component text based on component name

So I creat some TEdit components like this
var
lb : TLabel;
topLabel, i: Integer;
dbedit : TEdit;
begin
inherited;
topLabel := 40;
i := 0;
lb := TLabel.Create(nil);
lb.Parent := GroupBox2;
lb.Left := 245;
lb.Top := 20;
lb.Caption := 'ASD';
with DataModule.myStoredProc do begin
Close;
ParamByName('#Param1').AsInteger := 1;
ExecProc;
Open;
SetLength(nrPozitiiDinctionar,RecordCount);
First;
while not Eof do begin
lb := TLabel.Create(nil);
lb.Parent := GroupBox2;
lb.Left := 7;
lb.Top := topLabel ;
lb.Caption := FieldByName('X').AsString;
dbedit := TEdit.Create(nil);
dbedit.Name := 'Edit'+IntToStr(FieldByName('Poz').AsInteger);
dbedit.Text := '';
dbedit.Parent := GroupBox2;
dbedit.Height := 21;
dbedit.Width := 40;
dbedit.Left := 240;
dbedit.Top := lb.Top-3 ;
topLabel := topLabel + 30;
nrPozitiiDinctionar[i] := FieldByName('Poz').AsInteger;
i := i + 1;
Next;
end;
end;
end;
Then after the user add his input I run a function with this code
var
IDPoz, I : Integer;
dbedit : TEdit;
pctj,nume : string;
begin
for I := Low(nrPozitiiDinctionar) to High(nrPozitiiDinctionar) do
begin
nume := 'Edit'+IntToStr(nrPozitiiDinctionar[i]);
pctj := TEdit(FindComponent('Edit'+IntToStr(nrPozitiiDinctionar[i]))).Text;
with DateCOFurnizori.spCOFCmzFurnizoriEvaluarePozitii_Edit do begin
ParamByName('#IDEvaluare').AsInteger := StrToInt(Edit1.Text);
ParamByName('#IDPozitie').AsInteger := IDPoz;
ParamByName('#DictionarID').AsInteger := 9103;
ParamByName('#DictionarPozitiiID').AsInteger := nrPozitiiDinctionar[i];
ParamByName('#Punctaj').AsFloat := 1 ;//StrToFloat(pctj) ;
ParamByName('#DataEvaluare').AsDateTime := Now;
ExecProc;
IDPoz := IDPoz + 1;
end;
end;
This is only a portion of the code but this should relate to my problem.
When I use the debugger there is no value in pctj, what am I doing wrong? I try to get the value of the TEdits based on their names. What am I doing wrong with the FindComponent function?
You are not assigning an Owner to the TEdit controls, so that is why FindComponent() cannot find them. Either assign Self as the Owner (since you are calling Self.FindComponent()), or else store the TEdit pointers in a TList or TObjectList that you can loop through when needed.

Delphi XE6 firemonkey component alignment problems when added at runtime

i wanto dynamic add 5 TLable in my iOS app.
like this
Procedure Form1.FormCreate(Sender: TObject)
var
I: Integer;
begin
for I := 1 to 5 do
begin
with TLabel.Create(Self) do
begin
Parent := self;
Align := TAlignLayout.Top;
Height := 50;
Text := IntToStr(I);
end;
end;
end;
i think the order is 12345, but I get 15432.
What can I do to get the desired results?
You must give a chance to the aligning algorithm to do what you want.
procedure TForm1.FormCreate(Sender: TObject);
var
I: Integer;
begin
for I := 1 to 5 do
begin
with TLabel.Create(Self) do
begin
Parent := self;
Align := TAlignLayout.alTop;
Height := 50;
Position.Y := I*Height; //add this line
Text := IntToStr(I);
end;
end;
end;

How to show dialog box with two buttons ( Continue / Close ) in Delphi

I want to create a warning dialog box which asks the users if the information typed during signup was correct, and asks him wether he want to continue or close that dialog and correct his information.
var
td: TTaskDialog;
tb: TTaskDialogBaseButtonItem;
begin
td := TTaskDialog.Create(nil);
try
td.Caption := 'Warning';
td.Text := 'Continue or Close?';
td.MainIcon := tdiWarning;
td.CommonButtons := [];
tb := td.Buttons.Add;
tb.Caption := 'Continue';
tb.ModalResult := 100;
tb := td.Buttons.Add;
tb.Caption := 'Close';
tb.ModalResult := 101;
td.Execute;
if td.ModalResult = 100 then
ShowMessage('Continue')
else if td.ModalResult = 101 then
ShowMessage('Close');
finally
td.Free;
end;
end;
Note: This will only work on Windows Vista or later.
if delphi then
if mrYes=MessageDlg('Continue?',mtwarning,[mbYes, mbNo],0) then
begin
//do somthing
end
else
exit; //go out
var
AMsgDialog: TForm;
abutton: TButton;
bbutton: TButton;
begin
AMsgDialog := CreateMessageDialog('This is a test message.', mtWarning,[]);
abutton := TButton.Create(AMsgDialog);
bbutton := TButton.Create(AMsgDialog);
with AMsgDialog do
try
Caption := 'Dialog Title' ;
Height := 140;
AMsgDialog.Width := 260 ;
with abutton do
begin
Parent := AMsgDialog;
Caption := 'Continue';
Top := 67;
Left := 60;
// OnClick :tnotyfievent ;
end;
with bbutton do
begin
Parent := AMsgDialog;
Caption := 'Close';
Top := 67;
Left := 140;
//OnClick :tnotyfievent ;
end;
ShowModal ;
finally
abutton.Free;
bbutton.Free;
Free;
end;
Based on this:
procedure HookResourceString(rs: PResStringRec; newStr: PChar);
var
oldprotect: DWORD;
begin
VirtualProtect(rs, SizeOf(rs^), PAGE_EXECUTE_READWRITE, #oldProtect);
rs^.Identifier := Integer(newStr);
VirtualProtect(rs, SizeOf(rs^), oldProtect, #oldProtect);
end;
const
SContinue = 'Continue';
SClose = 'Close';
procedure TForm1.Button1Click(Sender: TObject);
begin
HookResourceString(#SMsgDlgOK, SContinue);
HookResourceString(#SMsgDlgCancel, SClose);
if MessageDlg('My Message', mtConfirmation, [mbOK, mbCancel], 0) = mrOK then
begin
// OK...
end;
end;

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