I am having problems with adding text I have entered into a tedit, into an record.
Here is the code i currently have:
procedure TForm7.AddNewQuestionClick(Sender: TObject);
var
w: integer;
QuestDesc, QuestAnsr: string;
begin
NewQuestID.text:=(GetNextQuestionID); //Increments QuestionID part of record
w:=Length(TQuestions);
SetLength(TQuestions, w+1);
QuestDesc:= NewQuestDesc.text;
QuestAnsr:= NewQuestAns.text;
TQuestionArray[w+1].Question:= QuestDesc; // Error on this line (No default property available)
TQuestionArray[w+1].Answer:= QuestAnsr;
end;
Here is the record I am trying to add to:
TQuestion = record
public
QuestionID: integer;
Question: shortstring;
Answer: shortstring;
procedure InitQuestion(anID:integer; aQ, anA:shortstring);
end;
TQuestionArray = array of TQuestion;
Any help solving this problem would be greatly appreciated.
You're missing a few things. You've declared a procedure to help initialize a new question - you should be using it.
This should get you going:
type
TQuestion = record
QuestionID: integer;
Question: ShortString;
Answer: ShortString;
procedure InitQuestion(anID: Integer; aQ, aAns: ShortString);
end;
TQuestionArray = array of TQuestion;
var
Form3: TForm3;
var
Questions: TQuestionArray;
procedure TForm7.AddNewQuestionClick(Sender: TObject);
begin
SetLength(Questions, Length(Questions) + 1);
Questions[High(Questions)].InitQuestion(GetNextQuestionID,
NewQuestDesc.Text,
NewQuestAns.Text);
end;
If you really want to do it individually setting the fields:
procedure TForm7.AddNewQuestionClick(Sender: TObject);
var
Idx: Integer;
begin
SetLength(Questions, Length(Questions) + 1);
Idx := High(Questions);
Questions[Idx].QuestionID := GetNextQuestionID;
Questions[Idx].Question := NewQuestDesc.Text;
Questions[Idx].Answer := NewQuestAns.Text;
end;
Related
As an exercise for myself, I'm trying to recreate the To-Do app from the (fascinating) todomvc.com web site. The UI looks like this:
A user writes a To-Do item in an Edit box control (above the crossed out "buy milk") and presses Enter. To-Do items appear below.
As you can see, each line includes a stylized radio control, the text, and a button with an image (red x). The button appears when a user hovers the cursor inside the line.
I don't care about the button, having an image, or appearing only upon OnEnter. I can't figure out how to make a similarly styled (ListView? ComboBox?) control with a radio control and button.
I'm using Delphi VCL, but could switch to FMX.
There really isn't any shortcut here: you simply need to write quite a lot of code. The Windows OS doesn't provide anything like this. I would implement from scratch using an empty window with custom GDI painting and mouse and keyboard input processing. It's not difficult at all, but it does require quite a lot of code.
That was a lot of words and no code.
As a remedy, here is a very quick demonstration control based on Direct2D (because I realised I really do need anti aliasing):
unit ItemListBox;
interface
uses
Windows, SysUtils, Types, UITypes, Classes, Controls, Graphics, Generics.Defaults,
Generics.Collections, Forms, Messages, Direct2D, D2D1;
type
TItem = class
strict private
FCaption: TCaption;
FChecked: Boolean;
FTag: NativeInt;
FOnChanged: TNotifyEvent;
procedure Changed;
procedure SetCaption(const Value: TCaption);
procedure SetChecked(const Value: Boolean);
public
property Caption: TCaption read FCaption write SetCaption;
property Checked: Boolean read FChecked write SetChecked;
property Tag: NativeInt read FTag write FTag;
property OnChanged: TNotifyEvent read FOnChanged write FOnChanged;
end;
TPart = (ilbpText, ilbpCheckBox, ilbpClearButton);
TItemListBox = class(TCustomControl)
strict private
FItems: TObjectList<TItem>;
FItemHeight: Integer;
FCanvas: TDirect2DCanvas;
FIndex: Integer;
FPart: TPart;
FMouseDownIndex: Integer;
FMouseDownPart: TPart;
FFocusIndex: Integer;
function GetItem(Index: Integer): TItem;
function GetItemCount: Integer;
procedure ItemChanged(Sender: TObject);
procedure DrawItem(Index: Integer; Item: TItem);
procedure DrawCheckBox(Index: Integer; Item: TItem; Hot: Boolean = False);
procedure DrawClearButton(Index: Integer; Visible: Boolean; Hot: Boolean = False);
function ItemRect(Index: Integer): TRect;
function TextRect(Index: Integer): TRect;
function CheckBoxRect(Index: Integer): TRect;
function ClearButtonRect(Index: Integer): TRect;
procedure CreateDeviceResources;
procedure HitTest(const P: TPoint; out Index: Integer; out Part: TPart);
procedure StateChange(ANewIndex: Integer; ANewPart: TPart);
function CanvasWidth: Integer;
function CanvasHeight: Integer;
protected
procedure Paint; override;
procedure WMPaint(var Message: TWMPaint); message WM_PAINT;
procedure WMSize(var Message: TWMSize); message WM_SIZE;
procedure WMEraseBkgnd(var Message: TWMEraseBkgnd); message WM_ERASEBKGND;
procedure CreateWnd; override;
procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X: Integer;
Y: Integer); override;
procedure MouseMove(Shift: TShiftState; X: Integer; Y: Integer); override;
procedure CMMouseLeave(var Message: TMessage); message CM_MOUSELEAVE;
procedure MouseUp(Button: TMouseButton; Shift: TShiftState; X: Integer;
Y: Integer); override;
procedure KeyDown(var Key: Word; Shift: TShiftState); override;
procedure WMGetDlgCode(var Message: TWMGetDlgCode); message WM_GETDLGCODE;
procedure WMSetFocus(var Message: TWMSetFocus); message WM_SETFOCUS;
procedure WMKillFocus(var Message: TWMKillFocus); message WM_KILLFOCUS;
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
property Canvas: TDirect2DCanvas read FCanvas;
function AddItem(const ACaption: string; AChecked: Boolean;
ATag: NativeInt = 0): Integer;
procedure RemoveItem(AIndex: Integer);
property Items[Index: Integer]: TItem read GetItem;
property ItemCount: Integer read GetItemCount;
published
property Align;
property AlignWithMargins;
property Anchors;
property Cursor;
property Font;
property Hint;
property PopupMenu;
property TabOrder;
property TabStop default True;
end;
procedure Register;
implementation
uses
Math;
procedure Register;
begin
RegisterComponents('Rejbrand 2020', [TItemListBox]);
end;
function Scale(X: Integer): Integer;
begin
Result := MulDiv(X, Screen.PixelsPerInch, 96);
end;
{ TItem }
procedure TItem.Changed;
begin
if Assigned(FOnChanged) then
FOnChanged(Self);
end;
procedure TItem.SetCaption(const Value: TCaption);
begin
if FCaption <> Value then
begin
FCaption := Value;
Changed;
end;
end;
procedure TItem.SetChecked(const Value: Boolean);
begin
if FChecked <> Value then
begin
FChecked := Value;
Changed;
end;
end;
{ TItemListBox }
function TItemListBox.AddItem(const ACaption: string; AChecked: Boolean;
ATag: NativeInt): Integer;
var
Item: TItem;
begin
Item := TItem.Create;
Item.Caption := ACaption;
Item.Checked := AChecked;
Item.OnChanged := ItemChanged;
Result := FItems.Add(Item);
InvalidateRect(Handle, ItemRect(Result), True);
end;
function TItemListBox.ClearButtonRect(Index: Integer): TRect;
begin
Result := Rect(CanvasWidth - 32, Index * FItemHeight, CanvasWidth,
(Index + 1) * FItemHeight);
end;
procedure TItemListBox.CMMouseLeave(var Message: TMessage);
begin
inherited;
StateChange(-1, ilbpText);
end;
constructor TItemListBox.Create(AOwner: TComponent);
begin
inherited;
FItems := TObjectList<TItem>.Create;
FItemHeight := 32;
FIndex := -1;
FMouseDownIndex := -1;
FFocusIndex := -1;
Color := clWindow;
TabStop := True;
end;
procedure TItemListBox.CreateDeviceResources;
begin
FreeAndNil(FCanvas);
FCanvas := TDirect2DCanvas.Create(Handle);
end;
procedure TItemListBox.CreateWnd;
begin
inherited;
CreateDeviceResources;
end;
destructor TItemListBox.Destroy;
begin
FreeAndNil(FItems);
FreeAndNil(FCanvas);
inherited;
end;
procedure TItemListBox.DrawClearButton(Index: Integer; Visible: Boolean; Hot: Boolean);
var
R: TRect;
begin
if not Visible then
Exit;
R := ClearButtonRect(Index);
InflateRect(R, -7, -7);
Canvas.Pen.Color := IfThen(Hot, clRed, clMaroon);
Canvas.Pen.Width := 2;
Canvas.MoveTo(R.Left, R.Top);
Canvas.LineTo(R.Right, R.Bottom);
Canvas.MoveTo(R.Right, R.Top);
Canvas.LineTo(R.Left, R.Bottom);
end;
procedure TItemListBox.DrawItem(Index: Integer; Item: TItem);
var
R: TRect;
S: string;
begin
// Background
Canvas.Brush.Color := clWindow;
Canvas.Brush.Style := bsSolid;
Canvas.Pen.Color := clWindowText;
Canvas.Pen.Width := 1;
Canvas.Pen.Style := psSolid;
R := ItemRect(Index);
Canvas.FillRect(R);
// Text
R := TextRect(Index);
S := Item.Caption;
Canvas.Font.Assign(Font);
Canvas.Font.Color := IfThen(Item.Checked, clGrayText, clWindowText);
if Item.Checked then
Canvas.Font.Style := [fsStrikeOut]
else
Canvas.Font.Style := [];
Canvas.TextRect(R, S, [tfSingleLine, tfEndEllipsis, tfVerticalCenter]);
// Check box
DrawCheckBox(Index, Item, (FIndex = Index) and (FPart = ilbpCheckBox));
// Clear button
DrawClearButton(Index, FIndex = Index, (FIndex = Index) and (FPart = ilbpClearButton));
// Focus indicator
if InRange(FFocusIndex, 0, FItems.Count - 1) and Focused then
begin
Canvas.Pen.Color := clSilver;
Canvas.Pen.Width := 1;
Canvas.Pen.Style := psSolid;
Canvas.Brush.Style := bsClear;
R := TextRect(FFocusIndex);
InflateRect(R, 0, -2);
Canvas.Rectangle(R);
end;
end;
procedure TItemListBox.DrawCheckBox(Index: Integer; Item: TItem;
Hot: Boolean);
var
R: TRect;
begin
R := CheckBoxRect(Index);
InflateRect(R, -5, -5);
Canvas.Pen.Color := clSilver;
Canvas.Pen.Width := 1;
Canvas.Brush.Color := IfThen(Hot, clSilver, clWhite);
Canvas.Ellipse(R);
if Assigned(Item) and Item.Checked then
begin
Canvas.Pen.Color := clGreen;
Canvas.Pen.Width := 2;
Canvas.MoveTo(R.Left + R.Width div 5, R.Bottom - R.Height div 2);
Canvas.LineTo(R.Left + Round(R.Width / 2.5), R.Bottom - Round(R.Height / 3.8));
Canvas.LineTo(R.Right - Round(R.Width / 4.5), R.Top + R.Height div 5);
end;
end;
function TItemListBox.GetItem(Index: Integer): TItem;
begin
Result := FItems[Index];
end;
function TItemListBox.GetItemCount: Integer;
begin
Result := FItems.Count;
end;
procedure TItemListBox.HitTest(const P: TPoint; out Index: Integer;
out Part: TPart);
var
i: Integer;
Q: TPoint;
begin
Q.X := MulDiv(P.X, 96, Screen.PixelsPerInch);
Q.Y := MulDiv(P.Y, 96, Screen.PixelsPerInch);
for i := 0 to FItems.Count - 1 do
if ItemRect(i).Contains(Q) then
begin
Index := i;
if CheckBoxRect(i).Contains(Q) then
Part := ilbpCheckBox
else if ClearButtonRect(i).Contains(Q) then
Part := ilbpClearButton
else
Part := ilbpText;
Exit;
end;
Index := -1;
Part := ilbpText;
end;
procedure TItemListBox.ItemChanged(Sender: TObject);
begin
Invalidate;
end;
function TItemListBox.ItemRect(Index: Integer): TRect;
begin
Result := Rect(0, Index * FItemHeight, CanvasWidth, (Index + 1) * FItemHeight);
end;
procedure TItemListBox.KeyDown(var Key: Word; Shift: TShiftState);
begin
inherited;
case Key of
VK_DOWN:
if Succ(FFocusIndex) <= FItems.Count - 1 then
begin
Inc(FFocusIndex);
Invalidate;
end;
VK_UP:
if Pred(FFocusIndex) >= 0 then
begin
Dec(FFocusIndex);
Invalidate;
end;
VK_HOME:
if FFocusIndex <> 0 then
begin
FFocusIndex := 0;
Invalidate;
end;
VK_END:
if FFocusIndex <> FItems.Count - 1 then
begin
FFocusIndex := FItems.Count - 1;
Invalidate;
end;
VK_SPACE:
if InRange(FFocusIndex, 0, FItems.Count - 1) then
FItems[FFocusIndex].Checked := not FItems[FFocusIndex].Checked;
VK_DELETE:
if InRange(FFocusIndex, 0, FItems.Count - 1) then
RemoveItem(FFocusIndex);
end;
end;
procedure TItemListBox.MouseDown(Button: TMouseButton; Shift: TShiftState; X,
Y: Integer);
begin
inherited;
if CanFocus then
SetFocus;
HitTest(Point(X, Y), FMouseDownIndex, FMouseDownPart);
if FFocusIndex <> FMouseDownIndex then
begin
FFocusIndex := FMouseDownIndex;
Invalidate;
end;
end;
procedure TItemListBox.MouseMove(Shift: TShiftState; X, Y: Integer);
var
NewIndex: Integer;
NewPart: TPart;
begin
inherited;
HitTest(Point(X, Y), NewIndex, NewPart);
StateChange(NewIndex, NewPart);
end;
procedure TItemListBox.MouseUp(Button: TMouseButton; Shift: TShiftState; X,
Y: Integer);
var
Index: Integer;
Part: TPart;
begin
HitTest(Point(X, Y), Index, Part);
if (Index <> -1) and (Index = FMouseDownIndex) and (Button = mbLeft) then
begin
if (Part = ilbpCheckBox) and (Part = FMouseDownPart) then
FItems[Index].Checked := not FItems[Index].Checked
else if (Part = ilbpClearButton) and (Part = FMouseDownPart) then
RemoveItem(Index);
end;
end;
procedure TItemListBox.Paint;
var
i: Integer;
begin
Canvas.RenderTarget.Clear(D2D1ColorF(clWhite));
for i := 0 to FItems.Count - 1 do
DrawItem(i, FItems[i]);
end;
procedure TItemListBox.RemoveItem(AIndex: Integer);
begin
FItems.Delete(AIndex);
FFocusIndex := EnsureRange(FFocusIndex, 0, FItems.Count - 1);
Invalidate;
end;
procedure TItemListBox.StateChange(ANewIndex: Integer; ANewPart: TPart);
var
OldIndex: Integer;
OldPart: TPart;
begin
OldIndex := FIndex;
OldPart := FPart;
FIndex := ANewIndex;
FPart := ANewPart;
if FIndex = OldIndex then
begin
if FPart <> OldPart then
begin
if ilbpCheckBox in [FPart, OldPart] then
InvalidateRect(Handle, CheckBoxRect(FIndex), True);
if ilbpClearButton in [FPart, OldPart] then
InvalidateRect(Handle, ClearButtonRect(FIndex), True);
end;
end
else
begin
InvalidateRect(Handle, ItemRect(OldIndex), True);
InvalidateRect(Handle, ItemRect(FIndex), True);
end;
end;
function TItemListBox.CanvasHeight: Integer;
begin
Result := MulDiv(ClientHeight, 96, Screen.PixelsPerInch);
end;
function TItemListBox.CanvasWidth: Integer;
begin
Result := MulDiv(ClientWidth, 96, Screen.PixelsPerInch);
end;
function TItemListBox.CheckBoxRect(Index: Integer): TRect;
begin
Result := Rect(0, Index * FItemHeight, 32, (Index + 1) * FItemHeight);
end;
function TItemListBox.TextRect(Index: Integer): TRect;
begin
Result := Rect(40, Index * FItemHeight, CanvasWidth - 40,
(Index + 1) * FItemHeight);
end;
procedure TItemListBox.WMEraseBkgnd(var Message: TWMEraseBkgnd);
begin
Message.Result := 1;
end;
procedure TItemListBox.WMGetDlgCode(var Message: TWMGetDlgCode);
begin
inherited;
Message.Result := Message.Result or DLGC_WANTARROWS;
end;
procedure TItemListBox.WMKillFocus(var Message: TWMKillFocus);
begin
inherited;
Invalidate;
end;
procedure TItemListBox.WMPaint(var Message: TWMPaint);
var
PaintStruct: TPaintStruct;
res: HRESULT;
begin
BeginPaint(Handle, PaintStruct);
try
if Assigned(FCanvas) then
begin
FCanvas.BeginDraw;
try
Paint;
finally
res := FCanvas.RenderTarget.EndDraw;
if res = D2DERR_RECREATE_TARGET then
CreateDeviceResources;
end;
end;
finally
EndPaint(Handle, PaintStruct);
end;
end;
procedure TItemListBox.WMSetFocus(var Message: TWMSetFocus);
begin
inherited;
Invalidate;
end;
procedure TItemListBox.WMSize(var Message: TWMSize);
var
S: TD2DSizeU;
begin
if Assigned(FCanvas) then
begin
S := D2D1SizeU(ClientWidth, ClientHeight);
ID2D1HwndRenderTarget(FCanvas.RenderTarget).Resize(S);
end;
Invalidate;
inherited;
end;
end.
Example (with a simple TEdit at the top):
But please notice that this is not a finished control; it's merely a very primitive sketch or prototype. It is not fully tested. In addition, a real control would have scrolling support and a keyboard interface. Since it is very late in Sweden right now, I don't really have time to add that at the moment.
Update: I added high-DPI support and a keyboard interface (up, down, home, end, space, delete):
I need to re-order a TObjectList, according to some rules. How can I achieve this?
So I add panels to a ScrollBox dinamically.
When I add them, I also add them to the ObjectList in the order that they are added at runtime, for future use. Then I can re-organize the panels in the scrollBox by drag/drop.
I want the ObjectList to mirror the same order that is set at runtime by drag/drop.
Here is my code:
var
MainForm: TMainForm;
PanelList,PanelListTMP:TObjectList;
implementation
...
procedure TMainForm.FormCreate(Sender: TObject);
begin
PanelList:=TObjectList.Create;
PanelListTMP:=TObjectList.Create;
end;
procedure TMainForm.Button1Click(Sender: TObject);
begin
AddPanel('0');
AddPanel('1');
AddPanel('2');
AddPanel('3');
AddPanel('4');
end;
procedure TMainForm.Addpanel(what:string);
var
pan:TPanel;
bv:TShape;
begin
pan:=TPanel.Create(self);
pan.Parent:=TheContainer;
pan.Height:=50;
pan.BevelOuter:=bvNone;
pan.BorderStyle:=bsNone;
pan.Ctl3D:=false;
pan.Name:='LayerPan'+what;
pan.Caption:=what;
pan.Align:=alBottom;
pan.OnMouseDown:=panMouseDown;
end;
procedure TMainForm.panMouseDown(Sender: TObject; Button: TMouseButton;Shift: TShiftState; X, Y: Integer);
var
i:integer;
idu:String;
panui:TPanel;
begin
panui:=Sender as TPanel;
panui.ParentColor:=false;
panui.BringToFront;
// DRAG DROP STUFF
ReleaseCapture;
panui.Perform(wm_nclbuttondown,HTCAPTION,0);
for i := 0 to MainForm.ComponentCount - 1 do
begin
if MainForm.Components[i] is TWinControl then
if TWinControl(MainForm.Components[i]) is TPanel then
if (TWinControl(MainForm.Components[i]) as TPanel).Parent=MainForm.TheContainer then
begin
(TWinControl(MainForm.Components[i]) as TPanel).Align:=alBottom;
end;
end;
TheContainer.ScrollInView(panui);
ReOrderPanels;
end;
Procedure TMainForm.ReOrderPanels;
begin
end;
What should I do in the ReOrderPanels procedure?
I was thinking about feeding the panels of the ScrollBox from bottom to top into a new TObjectList (PanelListTMP), clear the PanelList and re-add them from the PanelListTMP, but when I do that, I get an error: Access Violation, and EInvalidPointer - Invalid Pointer Operation
So this is what I thought:
procedure TMainForm.ReOrderPanels;
var
ctrl:TControl;
pos:TPoint;
pan:TPanel;
bad:boolean;
ord,i:integer;
begin
memo2.Lines.Add('*** new order START');
panelListTMP.Clear;
// scroll top
TheContainer.VertScrollBar.Position := 0;
// scroll down
TheContainer.VertScrollBar.Position := TheContainer.VertScrollBar.Range;
// get panel
Pos:=TheContainer.ClientOrigin;
Pos.Y:=Pos.Y+TheContainer.Height-5;
ctrl := FindVCLWindow(pos) ;
if ctrl is TPanel then
if TPanel(ctrl).Parent = TheContainer then
begin
pan:=(ctrl as TPanel);
panelListTMP.Add(pan);
end;
ord:=1;
bad:=false;
repeat
repeat
Pos.Y:=pos.Y-1;
until (FindVCLWindow(pos) is TPanel)and(FindVCLWindow(pos)<>pan);
if (FindVCLWindow(pos) is TPanel)and(FindVCLWindow(pos).Name<>'LayerPan') then
begin
pan:=FindVCLWindow(pos) as TPanel;
containeru.VertScrollBar.Position := 0;
containeru.ScrollInView(pan);
ord:=ord+1;
panelListTMP.Add(pan);
end
else
bad:=true;
until bad=true;
// and now I do the swap between the ObjectLists...
panelList.Clear;
for i:=0 to PanelListTMP.Count-1 do
begin
(PanelListTMP.Items[i] as TPanel).Parent:=containeru;
panelList.Add(PanelListTMP.Items[i]);
end;
end;
So I assume that because the ObjectList is storing pointers to the actual objects, then when I clear the initial ObjectList, the actual objects are freed, so the second ObjectList contains a list of pointers that are no longer viable...
But then how can I achieve what I want?
So on ButtonClick, I get a ObjectList that contains panels in the following order:
PanelList[0] - Panel0
PanelList[1] - Panel1
PanelList[2] - Panel2
PanelList[3] - Panel3
PanelList[4] - Panel4
After I drag - drop panels inside the ScrollBox, I can end up with an order like this (in the ScrollBox)
Panel3
panel1
Panel4
Panel2
Panel0
But in the ObjectList, the order is the same as before...
Again, I want to be able to have the ObjectList ordered according to the order of the panels from the scrollBox.
In the re-order procedure I actually get all the panels in the desired order.
I just need to have them in the same order in my ObjectList.
Is there any other way of doing this? Other that with me creating a new class that would hold an index beside a TPanel and use that in the ObjectList to maintain the order?
TObjectList has an OwnsObjects property that is True by default. Make sure to set it to False since you don't want the list to auto-free the objects as they are owned by the Form.
As for the actual sorting of the TObjectList, consider using its Sort() or SortList() method for that. After you have repositioned the Panels as desired within their container, call Sort() or SortList(). The sorting callback you provide will be given two object pointers at a time while the sorting is iterating the list. Use the current positions of the objects relative to each other to tell the list what order they should appear in.
Try something like this:
var
MainForm: TMainForm;
PanelList: TObjectList;
implementation
...
procedure TMainForm.FormCreate(Sender: TObject);
begin
PanelList := TObjectList.Create(False);
end;
procedure TMainForm.FormDestroy(Sender: TObject);
begin
PanelList.Free;
end;
procedure TMainForm.Button1Click(Sender: TObject);
begin
AddPanel('0');
AddPanel('1');
AddPanel('2');
AddPanel('3');
AddPanel('4');
end;
procedure TMainForm.Addpanel(what: string);
var
pan: TPanel;
bv: TShape;
begin
pan := TPanel.Create(Self);
try
pan.Parent := TheContainer;
pan.Height := 50;
pan.BevelOuter := bvNone;
pan.BorderStyle := bsNone;
pan.Ctl3D := false;
pan.Name := 'LayerPan'+what;
pan.Caption := what;
pan.Align := alBottom;
pan.OnMouseDown := panMouseDown;
PanelList.Add(pan);
except
pan.Free;
raise;
end;
end;
procedure TMainForm.panMouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
var
i: integer;
idu: String;
panui, pan: TPanel;
tmpList: TObjectList;
begin
panui := Sender as TPanel;
panui.ParentColor := false;
panui.BringToFront;
// DRAG DROP STUFF
ReleaseCapture;
panui.Perform(WM_NCLBUTTONDOWN, HTCAPTION, 0);
tmpList := TObjectList.Create(False);
try
for i := 0 to TheContainer.ControlCount - 1 do
begin
if TheContainer.Controls[i] is TPanel then
tmpList.Add(TPanel(TheContainer.Controls[i]));
end;
for i := 0 to tmpList.Count - 1 do
TPanel(tmpList[i]).Align := alBottom;
finally
tmpList.Free;
end;
TheContainer.ScrollInView(panui);
ReOrderPanels;
end;
function SortPanels(Item1, Item2: Pointer): Integer;
begin
Result := TPanel(Item2).Top - TPanel(Item1).Top;
end;
procedure TMainForm.ReOrderPanels;
begin
PanelList.Sort(SortPanels);
// Alternatively:
{
PanelList.SortList(
function(Item1, Item2: Pointer): Integer;
begin
Result := TPanel(Item2).Top - TPanel(Item1).Top;
end
);
}
end;
I think I found my answer using a temporary ObjectList and Extract(Object)
My code that seems to work is:
procedure TMainForm.ReOrderPanels;
var
ctrl:TControl;
pos:TPoint;
pan,panx:TPanel;
bad:boolean;
ord,i:integer;
begin
panelListTMP.Clear;
panelList.OwnsObjects:=false;
// scroll top
TheContainer.VertScrollBar.Position := 0;
// scroll down
TheContainer.VertScrollBar.Position := TheContainer.VertScrollBar.Range;
// get panel
Pos:=TheContainer.ClientOrigin;
Pos.Y:=Pos.Y+TheContainer.Height-5;
ctrl := FindVCLWindow(pos) ;
if ctrl is TPanel then
if TPanel(ctrl).Parent = TheContainer then
begin
pan:=(ctrl as TPanel);
panelListTMP.Add(PanelList.Extract(pan) as TPanel);
end;
ord:=1;
bad:=false;
repeat
repeat
Pos.Y:=pos.Y-1;
until (FindVCLWindow(pos) is TPanel)and(FindVCLWindow(pos)<>pan);
if (FindVCLWindow(pos) is TPanel)and(FindVCLWindow(pos).Name<>'LayerPan') then
begin
pan:=FindVCLWindow(pos) as TPanel;
TheContainer.VertScrollBar.Position := 0;
TheContainer.ScrollInView(pan);
ord:=ord+1;
panelListTMP.Add(PanelList.Extract(pan) as TPanel);
end
else
bad:=true;
until bad=true;
panelList.Clear;
panelListTMP.OwnsObjects:=false;
i:=0;
while (PanelListTMP.Count<>0) do
panelList.Add(PanelListTMP.Extract(PanelListTMP.Items[i]) as TPanel);
panelList.OwnsObjects:=true;
panelListTmp.Clear;
end;
I've found this great component and installed it, it's running great, but I have a slight problem with it. Which unfortunately I don't know how to do it myself.
Can someone help me add a new feature to this component . That would allow it take Images from ImageList ? I would fill up ImageList dynamicaly during my execution time.
Right now I'm doing the following to show a preview of the TILE :
procedure TTools.Preview_ImageExecute(Sender: TObject);
var image_temp : TBitmap;
begin
image_temp := TBitmap.Create;
LoadBitMap(ComboBox1.Text,image_temp,Main.ASDb1);
Image1.Picture.Bitmap:=image_temp;
image_temp.Free;
end;
Would like to use this somehow with the Image Grid... it should somehow allow me to load all my tiles.. I would use a For loop to fill it up...
Meanwhile I was playing with ListBox, and managed to do this :
procedure TTools.Lst1DrawItem(Control: TWinControl; Index: Integer;
Rect: TRect; State: TOwnerDrawState);
var CenterText : integer;
begin
Lst1.Canvas.FillRect(Rect);
Il1.Draw(lst1.Canvas,rect.Left +4, rect.Top +4, Index);
Centertext := (rect.Bottom - rect.Top -lst1.Canvas.TextHeight(text)) div 2;
Lst1.Canvas.TextOut(rect.left + il1.width + 8, rect.Top + CenterText, lst1.Items.Strings[index]);
end;
procedure TTools.Lst1MeasureItem(Control: TWinControl; Index: Integer;
var Height: Integer);
begin
Height := IL1.Height+4;
end;
procedure TTools.Button4Click(Sender: TObject);
var i : integer;
image_temp : TBitmap;
begin
image_temp := TBitmap.Create;
for i:=0 to Main.Images.Count-1 do
begin
Lst1.Items.Add(Main.Images.Item[i].Name);
LoadBitMap(Main.Images.Item[i].Name,image_temp,Main.ASDb1);
IL1.AddMasked(image_temp, clNone);
end;
Image_temp.Free;
end;
This works, if I have 0 Columns, but I cant get it working with say 4 columns , can someone help ?
Greetings
Robert
Never Mind ... I solved it like this :
procedure TTools.Button4Click(Sender: TObject);
var i : integer;
image_temp : TBitmap;
begin
image_temp := TBitmap.Create;
for i:=0 to Main.Images.Count-1 do
begin
LoadBitMap(Main.Images.Item[i].Name,image_temp,Main.ASDb1);
ListView1.Items.Add.Caption:=Main.Images.Item[i].Name;
ListView1.Items.Item[i].ImageIndex:=i;
IL1.AddMasked(image_temp, clNone);
end;
Image_temp.Free;
end;
This load's the image names as well as the images from my Asphyre Image list...
I create a Custom Tpanel and inside I put various Custom Components ...
procedure Panel_Comp(Location: TWinControl; NumOfComp: Integer;Left,Top,Height,width:Integer);
begin
MyPanel := TsPanel.Create(Conf);
MyPanel.Name := 'MyPanel' + IntToStr(NumOfComp);
MyPanel.Parent := Location;
MyPanel.Left := Left;
MyPanel.Top := Top;
MyPanel.Height := Height;
MyPanel.Width := width;
MyPanel.Caption := '';
end;
and i call it like this
Panel_Comp(Conf.ScrollBox1,1,8,10,70,322);
in the same logic i put inside the new panel other custom components including a tBitbtn the have a onclick event..
procedure BitBtn_Comp(Location: TWinControl; NumOfComp: Integer; Left,Top,Height,Width,ImageNum: Integer);
begin
MyBitBtn := TBitBtn.Create(Conf);
......
MyBitBtn.tag := NumOfComp;
MyBitBtn.OnClick:= Conf.CloseCurrentPanel;
end;
In the main Forn The TConf.CloseCurrentPanel;
procedure TConf.CloseCurrentPanel(Sender: TObject);
var
panelComp: TComponent;
begin
panelComp := FindComponentEx('Conf.MyPanel'+ IntToStr(TBitBtn(Sender).tag);
TPanel(panelComp).Free;
Application.ProcessMessages;
end;
When I call that I get access violation...
I think is something that I must free all the components inside the panel before free the panel but how I free the BitBtn before the panel and continue the action of the click event?
Here is the FindComponetEx function instead you need it...
function FindComponentEx(const Name: string): TComponent;
var
FormName: string;
CompName: string;
P: Integer;
Found: Boolean;
Form: TForm;
I: Integer;
begin
// Split up in a valid form and a valid component name
P := Pos('.', Name);
if P = 0 then
begin
raise Exception.Create('No valid form name given');
end;
FormName := Copy(Name, 1, P - 1);
CompName := Copy(Name, P + 1, High(Integer));
Found := False;
// find the form
for I := 0 to Screen.FormCount - 1 do
begin
Form := Screen.Forms[I];
// case insensitive comparing
if AnsiSameText(Form.Name, FormName) then
begin
Found := True;
Break;
end;
end;
if Found then
begin
for I := 0 to Form.ComponentCount - 1 do
begin
Result := Form.Components[I];
if AnsiSameText(Result.Name, CompName) then Exit;
end;
end;
Result := nil;
end;
The AV occurs because you are destroying a component (MyBitBtn) while it is still handling Windows messages. The solution is to postpone the destruction until later via PostMessage, similar to this:
unit Unit1;
interface
uses
Windows,
Messages,
SysUtils,
Variants,
Classes,
Graphics,
Controls,
Forms,
Dialogs,
ExtCtrls,
StdCtrls;
const
UM_DESTROYPANEL = WM_APP + 623; // some "unique" number; UM = user message
type
TConf = class(TForm)
Panel1: TPanel;
Button1: TButton;
procedure Button1Click(Sender: TObject);
strict private
procedure UMDestroyPanel(var Message: TMessage); message UM_DESTROYPANEL;
public
{ Public-Deklarationen }
end;
var
Conf: TConf;
implementation
{$R *.dfm}
procedure TConf.Button1Click(Sender: TObject);
begin
PostMessage(Handle, UM_DESTROYPANEL, 0, 0);
end;
procedure TConf.UMDestroyPanel(var Message: TMessage);
begin
Panel1.Free;
end;
end.
If needed you can use wParam and lParam to pass through parameters like so:
procedure TConf.Button1Click(Sender: TObject);
begin
PostMessage(Handle, UM_DESTROYPANEL, WPARAM(Panel1), 0);
end;
procedure TConf.UMDestroyPanel(var Message: TMessage);
begin
TObject(Message.WParam).Free;
end;
EDIT:
In your situation I'd probably rewrite TConf.CloseCurrentPanel like this:
procedure TConf.CloseCurrentPanel(Sender: TObject);
var
panelComp: TComponent;
begin
panelComp := FindComponentEx('Conf.MyPanel'+ IntToStr(TBitBtn(Sender).Tag);
PostMessage(Handle, UM_DESTROYPANEL, WPARAM(panelComp), 0);
end;
Alternatively you can pass through the Tag (might be the better solution because there's less casting involved):
procedure TConf.CloseCurrentPanel(Sender: TObject);
begin
PostMessage(Handle, UM_DESTROYPANEL, TBitBtn(Sender).Tag, 0);
end;
procedure TConf.UMDestroyPanel(var Message: TMessage);
var
panelComp: TComponent;
begin
panelComp := FindComponentEx('Conf.MyPanel'+ IntToStr(Message.WParam));
panelComp.Free;
end;
AFAICT the Application.ProcessMessages isn't needed.
procedure TConf.CloseCurrentPanel(Sender: TObject);
var
panelComp: TComponent;
begin
panelComp := FindComponentEx('Conf.MyPanel'+ IntToStr(TBitBtn(Sender).tag);
//Where you need to determine 'PanelComp' if there are.
if Assigned(panelComp) and (PanelComp is TPanel) then
TPanel(panelComp).Free;
Application.ProcessMessages;
end;
I'm having the next problem with SELECTNEXT and FINDNEXTCONTROL procedures in Delphi XE2 (Update 4 under WinXP Pro 32b), these procedures aren't working correctly. When a control gets focus and I try to pass to next control with the code below, it does not simply work:
procedure TformMain.cbServicioKeyPress(Sender: TObject; var Key: Char);
begin
if Key=#13 then
SelectNext(TWinControl(Sender), True, True);
end;
I've reviewed the code for FINDNEXTCONTROL and I've created a similar procedure and I've detected the problem is in these lines:
function TWinControl.FindNextControl(CurControl: TWinControl;
GoForward, CheckTabStop, CheckParent: Boolean): TWinControl;
...........
GetTabOrderList(List);
if List.Count > 0 then
begin
StartIndex := List.IndexOf(CurControl);
...........
end;
For any weird reason, procedure GETTABORDERLIST gives a list with valid references except for the current control focused, it does that LIST.INDEXOF returns -1, and the position in LIST object for current control focused is taken for another object whose NAME property is an empty string.
I developed this code:
procedure TformMain.GoNextControl(T: TWinControl; CheckTabStop: Boolean);
var
vParent, vNextChild : TWinControl;
List : TList;
CurIndex, i : Integer;
S:String;
begin
vParent:= Self; //T.Parent;
vNextChild:= nil;
List:= TList.Create;
try
vParent.GetTabOrderList(List);
if List.Count > 0 then
begin
//CurIndex:= List.IndexOf(T);
CurIndex:= -1;
for i:= 0 to List.Count-1 do begin
S:= TWinControl(List[i]).Name;
if S = EmptyStr then
begin
CurIndex:= i;
Break;
end;
end;
...........................
Anyone has a response for this anomaly or a better solution? Thanks in advance.
d
procedure TfrmMain.ControlKeyPress(Sender: TObject; var Key: Char);
begin
if Key = #13 then
begin
SelectNext(ActiveControl, TRUE, TRUE);
Key := #0;
end;
end;