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| ///////////////////////////////////////////////////////////////////////////
// //
// Copyright (c) 2015 by Charta Software B.V. //
// All rights reserved //
// //
// Version: 1.7.0.83525 //
// Web site: https://pascal.chartasoftware.com/ //
// //
// This code and information are provided "as is" without warranty of //
// any kind. Dissemination of this information or reproduction of //
// this material is strictly forbidden unless prior written permission //
// is obtained from Charta Software B.V.. //
// //
///////////////////////////////////////////////////////////////////////////
unit UserInterface.Control.Scroll.Panel;
interface
uses
Boolean,
Collection.List,
Event,
Geometry._2d.Integer32.Point,
Geometry._2d.Integer32.Size,
Integer._32,
Text,
UserInterface.Control,
UserInterface.Control.Panel,
UserInterface.Control.Scroll.Bar,
UserInterface.Control.Scroll.Model,
UserInterface.Control.ViewPort,
UserInterface.Keyboard.Modifiers,
UserInterface.Navigation;
type
TScrollBarsVisibility = record
public
VerticalVisible: TBoolean;
HorizontalVisible: TBoolean;
end;
TScrollPanel = class(TPanel)
private
FHorizontalScrollBar: TScrollBar;
FVerticalScrollBar: TScrollBar;
FVerticalScrollPolicy: TScrollPolicy;
FHorizontalScrollPolicy: TScrollPolicy;
FGridSize: TInteger32Size;
FMainPanel: TInteger32Point;
FPanels: TList<TList<TControl>>;
procedure SetVerticalScrollPolicy(const Value: TScrollPolicy);
procedure SetHorizontalScrollPolicy(const Value: TScrollPolicy);
procedure SetMainPanel(const Value: TInteger32Point);
procedure SetGridSize(const Size: TInteger32Size);
function GetPanel(const Position: TInteger32Point): TControl;
procedure SetPanel(const Location: TInteger32Point; Control: TControl);
private
LayingOutControls: TBoolean;
FocusedPanel: TControl;
procedure ValidateFocusedControl();
function DetermineVisibleScrollBarsForSize(AvailableSize: TInteger32Size): TScrollBarsVisibility;
procedure UpdateStyleFromMainPanel();
protected
procedure ReallocatePanels();
function GetCaption(): TText; override;
function GetCaptionVisible(): TBoolean; override;
procedure SetCaptionVisible(const Value: TBoolean); override;
protected
procedure ChildRethinksScrollBars(Child: TControl); override;
procedure DescendantFiresEvent(Descendant: TControl; Event: TEvent); override;
protected
function MainControl(): TControl;
function ViewPort(): TViewport;
protected
function ControlCanBeEntered(Control: TControl): TBoolean;
function ControlAbove(Location: TInteger32Point): TControl;
function ControlBelow(Location: TInteger32Point): TControl;
function ControlAtLeft(Location: TInteger32Point): TControl;
function ControlAtRight(Location: TInteger32Point): TControl;
protected
function Navigate(Direction: TNavigationDirection; KeyModifiers: TKeyModifiers): TBoolean; override;
function GetFocusedPanelLocation(): TInteger32Point;
procedure DescendantRequestsFocusInComposition(Descendant: TControl); override;
protected
function GetPreferredColumnWidth(Column: TInteger32): TInteger32;
function GetPreferredRowHeight(Row: TInteger32): TInteger32;
function GetFixedSize(): TInteger32Size;
function GetAvailableSize(): TInteger32Size;
procedure DetermineVisibleScrollBars();
procedure RepositionScrollBars();
procedure SetViewPortSize(const Size: TInteger32Size);
procedure AdjustScrollModel(Model: TScrollModel; AvailableSize: TInteger32; ScrollSize: TInteger32);
procedure UpdateViewPorts(ScrollModel: TScrollModel);
protected
function GetVerticalScrollBarIsVisible(): TBoolean;
procedure SetVerticalScrollBarIsVisible(Value: TBoolean);
function GetHorizontalScrollBarIsVisible(): TBoolean;
procedure SetHorizontalScrollBarIsVisible(Value: TBoolean);
procedure SetScrollBarIsVisible(ScrollBar: TScrollBar; Value: TBoolean);
function NeedsVerticalScrollBar(AvailableSize: TInteger32Size): TBoolean;
function NeedsHorizontalScrollBar(AvailableSize: TInteger32Size): TBoolean;
property VerticalScrollBarIsVisible: TBoolean read GetVerticalScrollBarIsVisible write SetVerticalScrollBarIsVisible;
property HorizontalScrollBarIsVisible: TBoolean read GetHorizontalScrollBarIsVisible write SetHorizontalScrollBarIsVisible;
protected
procedure SetHorizontalViewPortOffsets();
procedure SetVerticalViewPortOffsets();
procedure HandleViewPortMoved(ViewPort: TViewport);
function GetViewPortPanel(ViewPort: TViewport): TInteger32Point;
public
constructor Create(); override;
destructor Destroy(); override;
public
procedure LayoutControls(); override;
procedure SizeChanged(); override;
function HandleEvent(Event: TEvent): TBoolean; override;
public
function DefaultControlToFocus(): TControl; override;
function CompositeControlHasFocus(): TBoolean; override;
function ChildHasCompositionFocus(ChildControl: TControl): TBoolean; override;
function ChildWithCompositionFocus(): TControl; override;
function IsComposition(): TBoolean; override;
function GetPreferredSize(AvailableSize: TInteger32Size): TInteger32Size; override;
function NextInKeyboardInputChain(): TControl; override;
public
property GridSize: TInteger32Size read FGridSize write SetGridSize;
property MainPanel: TInteger32Point read FMainPanel write SetMainPanel;
property Panel[const Position: TInteger32Point]: TControl read GetPanel write SetPanel;
property VerticalScrollBar: TScrollBar read FVerticalScrollBar;
property HorizontalScrollBar: TScrollBar read FHorizontalScrollBar;
property VerticalScrollPolicy: TScrollPolicy read FVerticalScrollPolicy write SetVerticalScrollPolicy;
property HorizontalScrollPolicy: TScrollPolicy read FHorizontalScrollPolicy write SetHorizontalScrollPolicy;
end;
implementation
uses
CumulativeSizes.Sizable,
Geometry._2d.Dimension,
Geometry._2d.Integer32.Rectangle,
Mathematics,
Object_.List,
Reference.User,
UserInterface.Control.Event;
{ TScrollPanel }
procedure TScrollPanel.AdjustScrollModel(Model: TScrollModel; AvailableSize: TInteger32; ScrollSize: TInteger32);
var
Position: TInteger32;
begin
Position := Model.Position;
if Position > ScrollSize - AvailableSize then
Position := Maximum(0, ScrollSize - AvailableSize);
Model.SetScrollData(Maximum(0, ScrollSize), AvailableSize, Position);
end;
function TScrollPanel.ChildHasCompositionFocus(ChildControl: TControl): TBoolean;
begin
Result := ChildControl = FocusedPanel;
end;
procedure TScrollPanel.ChildRethinksScrollBars(Child: TControl);
begin
LayoutControls();
end;
function TScrollPanel.ChildWithCompositionFocus(): TControl;
begin
Result := FocusedPanel;
end;
function TScrollPanel.CompositeControlHasFocus(): TBoolean;
var
FocusManager: TKeyboardFocusManager;
FocusedControl: TControl;
begin
FocusManager := GetFocusManager();
if FocusManager <> nil then
begin
FocusedControl := FocusManager.FocusedControl;
Result := (FocusedControl <> nil) and (FocusedControl.GetRootEmbellishment().ParentControl = Self);
end
else
Result := False;
end;
function TScrollPanel.ControlAbove(Location: TInteger32Point): TControl;
begin
Result := nil;
Dec(Location.Y);
while (Result = nil) and (Location.Y >= 0) do
begin
if ControlCanBeEntered(Panel[Location]) then
Result := Panel[Location]
else
Dec(Location.Y);
end;
end;
function TScrollPanel.ControlAtLeft(Location: TInteger32Point): TControl;
begin
Result := nil;
Dec(Location.X);
while (Result = nil) and (Location.X >= 0) do
begin
if ControlCanBeEntered(Panel[Location]) then
Result := Panel[Location]
else
Dec(Location.X);
end;
end;
function TScrollPanel.ControlAtRight(Location: TInteger32Point): TControl;
begin
Result := nil;
Inc(Location.X);
while (Result = nil) and (Location.X < GridSize.Width) do
begin
if ControlCanBeEntered(Panel[Location]) then
Result := Panel[Location]
else
Inc(Location.X);
end;
end;
function TScrollPanel.ControlBelow(Location: TInteger32Point): TControl;
begin
Result := nil;
Inc(Location.Y);
while (Result = nil) and (Location.Y < GridSize.Height) do
begin
if ControlCanBeEntered(Panel[Location]) then
Result := Panel[Location]
else
Inc(Location.Y);
end;
end;
function TScrollPanel.ControlCanBeEntered(Control: TControl): TBoolean;
begin
// TODO: We might want to use an other criterion than control size to
// determine whether it can be entered
Result := (Control <> nil) and (Control.Height > 0) and (Control.Width > 0);
end;
constructor TScrollPanel.Create();
begin
inherited Create();
FVerticalScrollBar := TScrollBar.Create();
FVerticalScrollBar.Dimension := T2dDimension.Vertical;
FHorizontalScrollBar := TScrollBar.Create();
FHorizontalScrollBar.Dimension := T2dDimension.Horizontal;
VerticalScrollBar.Model := TScrollModel.Create();
HorizontalScrollBar.Model := TScrollModel.Create();
VerticalScrollBar.Model.Listeners.Add(Self);
HorizontalScrollBar.Model.Listeners.Add(Self);
FPanels := TObjectList<TList<TControl>>.Create();
GridSize := TInteger32Size.New(1, 1);
MainPanel := TInteger32Point.New(0, 0);
end;
function TScrollPanel.DefaultControlToFocus(): TControl;
begin
if FocusedPanel <> nil then
Result := FocusedPanel
else
Result := MainControl;
Result := Result.DefaultControlToFocus;
end;
procedure TScrollPanel.DescendantFiresEvent(Descendant: TControl; Event: TEvent);
var
ControlEvent: TControlEvent;
Control: TControl;
begin
if Event is TControlEvent then
begin
ControlEvent := Event as TControlEvent;
Control := ControlEvent.GetControl();
if Event is TControlGotFocusEvent then
FocusedPanel := Control
else if Event is TViewportMovedEvent then
HandleViewPortMoved(Descendant as TViewport)
else if Event is TControlStyleChanged then
begin
if (ViewPort <> nil) and (Control = MainControl) then
UpdateStyleFromMainPanel();
end;
end;
inherited DescendantFiresEvent(Descendant, Event);
end;
procedure TScrollPanel.DescendantRequestsFocusInComposition(Descendant: TControl);
var
PanelLosingFocus: TControl;
begin
PanelLosingFocus := FocusedPanel;
FocusedPanel := Descendant;
if FocusedPanel <> nil then
FocusedPanel.GainedFocusInComposition();
if PanelLosingFocus <> nil then
PanelLosingFocus.LostFocusInComposition();
if CompositeControlHasFocus then
Descendant.RequestFocus();
end;
destructor TScrollPanel.Destroy();
begin
FPanels.Free();
ChildControls.Remove(VerticalScrollBar);
ChildControls.Remove(HorizontalScrollBar);
VerticalScrollBar.Model.Free();
HorizontalScrollBar.Model.Free();
VerticalScrollBar.Free();
HorizontalScrollBar.Free();
inherited Destroy();
end;
procedure TScrollPanel.DetermineVisibleScrollBars();
var
ScrollBarsVisibility: TScrollBarsVisibility;
begin
ScrollBarsVisibility := DetermineVisibleScrollBarsForSize(GetAvailableSize());
VerticalScrollBarIsVisible := ScrollBarsVisibility.VerticalVisible;
HorizontalScrollBarIsVisible := ScrollBarsVisibility.HorizontalVisible;
end;
function TScrollPanel.DetermineVisibleScrollBarsForSize(AvailableSize: TInteger32Size): TScrollBarsVisibility;
var
VerticalScrollBarNeeded: TBoolean;
HorizontalScrollBarNeeded: TBoolean;
begin
Result.VerticalVisible := VerticalScrollBarIsVisible;
Result.HorizontalVisible := HorizontalScrollBarIsVisible;
if Result.VerticalVisible and (VerticalScrollPolicy <> spAsNeeded) then
Dec(AvailableSize.Width, VerticalScrollBar.GetPreferredSize(AvailableSize).Width);
if Result.HorizontalVisible and (HorizontalScrollPolicy <> spAsNeeded) then
Dec(AvailableSize.Height, HorizontalScrollBar.GetPreferredSize(AvailableSize).Height);
if (VerticalScrollPolicy = spAsNeeded) and (HorizontalScrollPolicy = spAsNeeded) then
begin
VerticalScrollBarNeeded := NeedsVerticalScrollBar(AvailableSize);
HorizontalScrollBarNeeded := NeedsHorizontalScrollBar(AvailableSize);
if VerticalScrollBarNeeded then
begin
Result.VerticalVisible := True;
Dec(AvailableSize.Width, VerticalScrollBar.GetPreferredSize(AvailableSize).Width);
Result.HorizontalVisible := NeedsHorizontalScrollBar(AvailableSize);
end
else if HorizontalScrollBarNeeded then
begin
Result.HorizontalVisible := True;
Dec(AvailableSize.Height, HorizontalScrollBar.GetPreferredSize(AvailableSize).Height);
Result.VerticalVisible := NeedsVerticalScrollBar(AvailableSize);
end
else
begin
Result.VerticalVisible := False;
Result.HorizontalVisible := False;
end;
end
else if VerticalScrollPolicy = spAsNeeded then
Result.VerticalVisible := NeedsVerticalScrollBar(AvailableSize)
else if HorizontalScrollPolicy = spAsNeeded then
Result.HorizontalVisible := NeedsHorizontalScrollBar(AvailableSize);
VerticalScrollBarIsVisible := Result.VerticalVisible;
HorizontalScrollBarIsVisible := Result.HorizontalVisible;
end;
function TScrollPanel.GetAvailableSize(): TInteger32Size;
begin
Result := Size - GetFixedSize();
end;
function TScrollPanel.GetCaption(): TText;
begin
Result := MainControl.Caption;
end;
function TScrollPanel.GetCaptionVisible(): TBoolean;
begin
Result := MainControl.CaptionVisible;
end;
function TScrollPanel.GetFixedSize(): TInteger32Size;
var
i: TInteger32;
begin
Result := TInteger32Size.New(0, 0);
for i := 0 to MainPanel.Y - 1 do
Inc(Result.Height, GetPreferredRowHeight(i));
for i := MainPanel.Y + 1 to GridSize.Height - 1 do
Inc(Result.Height, GetPreferredRowHeight(i));
for i := 0 to MainPanel.X - 1 do
Inc(Result.Width, GetPreferredColumnWidth(i));
for i := MainPanel.X + 1 to GridSize.Width - 1 do
Inc(Result.Width, GetPreferredColumnWidth(i));
end;
function TScrollPanel.GetFocusedPanelLocation(): TInteger32Point;
var
PanelToFind: TControl;
Position: TInteger32Point;
begin
Result := TInteger32Point.New(-1, -1);
if FocusedPanel <> nil then
begin
PanelToFind := FocusedPanel.GetRootEmbellishment();
Position.Y := 0;
while (Result.X = -1) and (Position.Y < GridSize.Height) do
begin
Position.X := 0;
while (Result.X = -1) and (Position.X < GridSize.Width) do
if Panel[Position] = PanelToFind then
Result := Position
else
Inc(Position.X);
Inc(Position.Y);
end;
end;
end;
function TScrollPanel.GetHorizontalScrollBarIsVisible(): TBoolean;
begin
Result := ChildControls.Contains(HorizontalScrollBar);
end;
function TScrollPanel.GetPanel(const Position: TInteger32Point): TControl;
begin
Result := FPanels[Position.Y][Position.X];
end;
function TScrollPanel.GetPreferredColumnWidth(Column: TInteger32): TInteger32;
var
i: TInteger32;
Control: TControl;
begin
Result := 0;
for i := 0 to GridSize.Height - 1 do
begin
Control := Panel[TInteger32Point.New(Column, i)];
if Control <> nil then
Result := Maximum(Result, Control.GetPreferredSize(TInteger32Size.Maximum).Width);
end;
end;
function TScrollPanel.GetPreferredRowHeight(Row: TInteger32): TInteger32;
var
i: TInteger32;
Control: TControl;
begin
Result := 0;
for i := 0 to GridSize.Width - 1 do
begin
Control := Panel[TInteger32Point.New(i, Row)];
if Control <> nil then
Result := Maximum(Result, Control.GetPreferredSize(TInteger32Size.Maximum).Height);
end;
end;
function TScrollPanel.GetVerticalScrollBarIsVisible(): TBoolean;
begin
Result := ChildControls.Contains(VerticalScrollBar);
end;
function TScrollPanel.GetViewPortPanel(ViewPort: TViewport): TInteger32Point;
var
Position: TInteger32Point;
begin
Result := TInteger32Point.New(-1, -1);
Position.Y := 0;
while (Result.X = -1) and (Position.Y < GridSize.Height) do
begin
Position.X := 0;
while (Result.X = -1) and (Position.X < GridSize.Width) do
begin
if Panel[Position] = ViewPort then
Result := Position
else
Inc(Position.X);
end;
Inc(Position.Y);
end;
end;
function TScrollPanel.HandleEvent(Event: TEvent): TBoolean;
var
ScrollEvent: TScrollEvent;
begin
if Event is TScrollEvent then
begin
ScrollEvent := Event as TScrollEvent;
Result := (ScrollEvent.Model = HorizontalScrollBar.Model) or (ScrollEvent.Model = VerticalScrollBar.Model);
if Result then
UpdateViewPorts(ScrollEvent.Model);
end
else
Result := inherited HandleEvent(Event);
end;
procedure TScrollPanel.HandleViewPortMoved(ViewPort: TViewport);
var
Panel: TInteger32Point;
begin
Panel := GetViewPortPanel(ViewPort);
if Panel.X = MainPanel.X then
HorizontalScrollBar.Model.Position := ViewPort.Offset.X;
if Panel.Y = MainPanel.Y then
VerticalScrollBar.Model.Position := ViewPort.Offset.Y;
end;
function TScrollPanel.IsComposition(): TBoolean;
begin
Result := True;
end;
procedure TScrollPanel.LayoutControls();
begin
if not LayingOutControls then
begin
LayingOutControls := True;
DetermineVisibleScrollBars();
RepositionScrollBars();
LayingOutControls := False;
end;
end;
function TScrollPanel.MainControl(): TControl;
begin
Result := ViewPort.Control;
end;
function TScrollPanel.Navigate(Direction: TNavigationDirection; KeyModifiers: TKeyModifiers): TBoolean;
var
CurrentLocation: TInteger32Point;
NextControl: TControl;
Fast: TBoolean;
begin
Result := Direction in [TNavigationDirection.Up, TNavigationDirection.Down, TNavigationDirection.Right, TNavigationDirection.Left];
if Result then
begin
CurrentLocation := GetFocusedPanelLocation();
NextControl := nil;
case Direction of
TNavigationDirection.Down:
NextControl := ControlBelow(CurrentLocation);
TNavigationDirection.Up:
NextControl := ControlAbove(CurrentLocation);
TNavigationDirection.Right:
NextControl := ControlAtRight(CurrentLocation);
TNavigationDirection.Left:
NextControl := ControlAtLeft(CurrentLocation);
end;
Result := NextControl <> nil;
if Result then
begin
Fast := KeyModifiers = [TKeyModifier.Control];
case Direction of
TNavigationDirection.Down:
NextControl.EnterFromTop(Fast);
TNavigationDirection.Up:
NextControl.EnterFromBottom(Fast);
TNavigationDirection.Right:
NextControl.EnterFromLeft(Fast);
TNavigationDirection.Left:
NextControl.EnterFromRight(Fast);
end;
end;
end;
end;
function TScrollPanel.NeedsHorizontalScrollBar(AvailableSize: TInteger32Size): TBoolean;
begin
Result := ViewPort.GetScrollSize(AvailableSize).Width > AvailableSize.Width;
end;
function TScrollPanel.NeedsVerticalScrollBar(AvailableSize: TInteger32Size): TBoolean;
begin
Result := ViewPort.GetScrollSize(AvailableSize).Height > AvailableSize.Height;
end;
function TScrollPanel.NextInKeyboardInputChain(): TControl;
begin
Result := FocusedPanel;
end;
function TScrollPanel.GetPreferredSize(AvailableSize: TInteger32Size): TInteger32Size;
var
FixedSize: TInteger32Size;
ScrollBarSize: TInteger32Size;
begin
FixedSize := GetFixedSize();
Result := Panel[MainPanel].GetPreferredSize(AvailableSize - FixedSize) + FixedSize;
if (Result.Height > AvailableSize.Height) and (AvailableSize.Width > Result.Width) then
begin
ScrollBarSize := VerticalScrollBar.GetPreferredSize(TInteger32Size.New(AvailableSize.Width - Result.Width, AvailableSize.Height));
Inc(Result.Width, ScrollBarSize.Width);
end
else if (Result.Width > AvailableSize.Width) and (AvailableSize.Height > Result.Height) then
begin
ScrollBarSize := HorizontalScrollBar.GetPreferredSize(TInteger32Size.New(AvailableSize.Width, AvailableSize.Height - Result.Height));
Inc(Result.Height, ScrollBarSize.Height);
end;
end;
procedure TScrollPanel.ReallocatePanels();
var
Index: TInteger32;
Row: TList<TControl>;
begin
FPanels.Clear();
FPanels.Capacity := GridSize.Height;
for Index := 1 to GridSize.Height do
begin
Row := TObjectList<TControl>.Create();
Row.ElementManager := TReferenceUser<TControl>.Create();
Row.Count := GridSize.Width;
FPanels.Add(Row);
end;
end;
procedure TScrollPanel.RepositionScrollBars();
var
AvailableSize: TInteger32Size;
ControlSize: TInteger32Size;
ScrollBarWidth: TInteger32;
ScrollBarHeight: TInteger32;
begin
AvailableSize := GetAvailableSize();
if VerticalScrollBarIsVisible then
begin
ScrollBarWidth := VerticalScrollBar.GetPreferredSize(AvailableSize).Width;
AvailableSize.Width := Maximum(0, AvailableSize.Width - ScrollBarWidth);
end
else
ScrollBarWidth := 0;
if HorizontalScrollBarIsVisible then
begin
ScrollBarHeight := HorizontalScrollBar.GetPreferredSize(AvailableSize).Height;
AvailableSize.Height := Maximum(0, AvailableSize.Height - ScrollBarHeight);
end
else
ScrollBarHeight := 0;
ControlSize := MainControl.GetScrollSize(AvailableSize);
if VerticalScrollBarIsVisible then
VerticalScrollBar.Bounds := TInteger32Rectangle.New(TInteger32Point.New(Width - ScrollBarWidth, 0), TInteger32Size.New(ScrollBarWidth, Height - ScrollBarHeight))
else
ControlSize.Height := AvailableSize.Height;
if HorizontalScrollBarIsVisible then
HorizontalScrollBar.Bounds := TInteger32Rectangle.New(TInteger32Point.New(0, Height - ScrollBarHeight), TInteger32Size.New(Width - ScrollBarWidth, ScrollBarHeight))
else
ControlSize.Width := AvailableSize.Width;
SetViewPortSize(AvailableSize);
ControlSize := MainControl.GetScrollSize(AvailableSize);
AdjustScrollModel(HorizontalScrollBar.Model, AvailableSize.Width, ControlSize.Width);
AdjustScrollModel(VerticalScrollBar.Model, AvailableSize.Height, ControlSize.Height);
ViewPort.ValidateOffset();
end;
procedure TScrollPanel.SetCaptionVisible(const Value: TBoolean);
begin
MainControl.CaptionVisible := Value;
end;
procedure TScrollPanel.SetGridSize(const Size: TInteger32Size);
begin
if Size <> GridSize then
begin
FGridSize := Size;
ReallocatePanels();
end;
end;
procedure TScrollPanel.SetHorizontalScrollBarIsVisible(Value: TBoolean);
begin
SetScrollBarIsVisible(HorizontalScrollBar, Value);
end;
procedure TScrollPanel.SetHorizontalScrollPolicy(const Value: TScrollPolicy);
begin
if Value <> HorizontalScrollPolicy then
begin
FHorizontalScrollPolicy := Value;
LayoutControls();
end;
end;
procedure TScrollPanel.SetHorizontalViewPortOffsets();
var
i: TInteger32;
ViewPort: TViewport;
begin
for i := 0 to GridSize.Height - 1 do
begin
ViewPort := Panel[TInteger32Point.New(MainPanel.X, i)] as TViewport;
ViewPort.SetOffset(TInteger32Point.New(HorizontalScrollBar.Model.Position, ViewPort.Offset.Y));
end;
end;
procedure TScrollPanel.SetMainPanel(const Value: TInteger32Point);
begin
FMainPanel := Value;
ValidateFocusedControl();
UpdateStyleFromMainPanel();
end;
procedure TScrollPanel.SetViewPortSize(const Size: TInteger32Size);
var
Rows: TSizableCumulativeSizes;
Columns: TSizableCumulativeSizes;
Row: TInteger32;
Column: TInteger32;
Control: TControl;
ControlPosition: TInteger32Point;
ControlSize: TInteger32Size;
begin
// TODO: Rows should be a member of a TScrollGridPanel and should be the authority on view port sizes
Rows := TSizableCumulativeSizes.Create();
Rows.Count := GridSize.Height;
for Row := 0 to MainPanel.Y - 1 do
Rows.SetItemSize(Row, GetPreferredRowHeight(Row), False);
for Row := MainPanel.Y + 1 to GridSize.Height - 1 do
Rows.SetItemSize(Row, GetPreferredRowHeight(Row), False);
Rows.SetItemSize(MainPanel.Y, Size.Height, False);
// TODO: Columns should be a member of a TScrollGridPanel and should be the authority on view port sizes
Columns := TSizableCumulativeSizes.Create();
Columns.Count := GridSize.Width;
for Column := 0 to MainPanel.X - 1 do
Columns.SetItemSize(Column, GetPreferredColumnWidth(Column), False);
for Column := MainPanel.X + 1 to GridSize.Width - 1 do
Columns.SetItemSize(Column, GetPreferredColumnWidth(Column), False);
Columns.SetItemSize(MainPanel.X, Size.Width, False);
ControlPosition.Y := 0;
for Row := 0 to GridSize.Height - 1 do
begin
ControlSize.Height := Rows.Size(Row);
ControlPosition.X := 0;
for Column := 0 to GridSize.Width - 1 do
begin
ControlSize.Width := Columns.Size(Column);
Control := Panel[TInteger32Point.New(Column, Row)];
if Control <> nil then
begin
Control.Bounds := TInteger32Rectangle.New(ControlPosition, ControlSize);
(Control as TViewport).Control.Size := Control.GetScrollSize(Control.Size);
end;
Inc(ControlPosition.X, ControlSize.Width);
end;
Inc(ControlPosition.Y, ControlSize.Height);
end;
Columns.Free();
Rows.Free();
end;
procedure TScrollPanel.SetPanel(const Location: TInteger32Point; Control: TControl);
var
CurrentControl: TControl;
ViewPort: TViewport;
ControlSize: TInteger32Size;
begin
CurrentControl := Panel[Location];
if CurrentControl <> nil then
ChildControls.Remove(CurrentControl);
ControlSize := Control.Size;
ViewPort := TViewport.Create();
ViewPort.Control := Control;
Control.Size:= ControlSize;
FPanels[Location.Y][Location.X] := ViewPort;
if Control <> nil then
ChildControls.Add(ViewPort);
ValidateFocusedControl();
if Location = MainPanel then
UpdateStyleFromMainPanel();
end;
procedure TScrollPanel.SetScrollBarIsVisible(ScrollBar: TScrollBar; Value: TBoolean);
begin
// TODO: We insert scroll bars at the front to prevent problems when scroll bars are removed during painting
SetChildControlVisible(ScrollBar, Value, TListEndPoint.Head);
if not Value then
ScrollBar.Model.Position := 0;
end;
procedure TScrollPanel.SetVerticalScrollBarIsVisible(Value: TBoolean);
begin
SetScrollBarIsVisible(VerticalScrollBar, Value);
end;
procedure TScrollPanel.SetVerticalScrollPolicy(const Value: TScrollPolicy);
begin
if Value <> VerticalScrollPolicy then
begin
FVerticalScrollPolicy := Value;
LayoutControls();
end;
end;
procedure TScrollPanel.SetVerticalViewPortOffsets();
var
i: TInteger32;
ViewPort: TViewport;
begin
for i := 0 to GridSize.Width - 1 do
begin
ViewPort := Panel[TInteger32Point.New(i, MainPanel.Y)] as TViewport;
ViewPort.SetOffset(TInteger32Point.New(ViewPort.Offset.X, VerticalScrollBar.Model.Position));
end;
end;
procedure TScrollPanel.SizeChanged();
begin
LayoutControls();
inherited SizeChanged();
end;
procedure TScrollPanel.UpdateStyleFromMainPanel();
begin
if ViewPort <> nil then
begin
// TODO: We probably have to take FixedSize into account
Style.Width.Value := MainControl.Style.Width.Value;
Style.Height.Value := MainControl.Style.Height.Value;
end;
end;
procedure TScrollPanel.UpdateViewPorts(ScrollModel: TScrollModel);
begin
if ScrollModel = HorizontalScrollBar.Model then
begin
SetHorizontalViewPortOffsets();
Invalidate();
end
else if ScrollModel = VerticalScrollBar.Model then
begin
SetVerticalViewPortOffsets();
Invalidate();
end;
end;
procedure TScrollPanel.ValidateFocusedControl();
begin
if (FocusedPanel = nil) and (ViewPort <> nil) then
FocusedPanel := MainControl;
end;
function TScrollPanel.ViewPort(): TViewport;
begin
Result := Panel[MainPanel] as TViewport;
end;
end.
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