Frequently Asked Component Specific Questions
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Drag drop in TAdvSmoothImageListBox
A sample which demonstrates drag drop on a TAdvSmoothImageListBox http://www.tmssoftware.net/public/Demo_DragDrop.zip
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How to disable a key
To disable a key, handle AdvSysKeyboardHook and set Allow parameter = false for key you want to display
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Drag & drop
This component is functionally equivalent to a standard TListView.
Drag & drop is handled by either setting AdvListView.DragMode = dmManual and implement a BeginDrag from an OnMouseMove for example or set AdvListView.DragMode = dmAuto and handle OnDragStart and other drag & drop related events.
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Moving and resizing panels at runtime
To move the panel, you'll need to set AdvPanel.CanMove = true and also set AdvPanel.Caption.Visible = true as moving is done by dragging the caption.
To re-size the panel, set AdvPanel.CanSize := true;
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How to autosize the component after loading a PNG file with AdvOfficeImage.Picture.LoadFromFile
Please use code similar to:
begin AdvOfficeImage1.Picture.LoadFromFile('c:\temp\weather.png'); AdvOfficeImage1.Width := AdvOfficeImage1.Picture.Width; AdvOfficeImage1.Height := AdvOfficeImage1.Picture.Height; end;
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Create descending class with custom TMsgCollectionItem classes
Starting from version 1.8, it is possible to create a descendent class of TAdvAlertWindow where it is possible to use a custom extended class of TMsgCollectionItem as AlertMessages collection. This code makes it clear how this can be done:
type TMsgCollectionItemEx = class(TMsgCollectionItem) private FExtra: string; published property Extra: string read FExtra write FExtra; end; TMsgCollectionEx = class(TMsgCollection) protected function GetItemClass: TCollectionItemClass; override; end; TAdvAlertWindowEx = class(TAdvAlertWindow) protected function CreateMsgCollection: TMsgCollection; override; end; implementation { TMsgCollectionEx } function TMsgCollectionEx.GetItemClass: TCollectionItemClass; begin Result := TMsgCollectionItemEx; end; { TAdvAlertWindowEx } function TAdvAlertWindowEx.CreateMsgCollection: TMsgCollection; begin Result := TMsgCollectionEx.Create(Self); end;
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Compiling / Distribution for iOS
When creating your project in Delphi, and afterwards, generate a xcode compatible project (dpr2xcode.exe) there are some additional steps to be taken before the project will compile in xcode.
In the generated iOS version you will notice an xcode folder, with an xcode project file. Before opening this project file in xcode you need to copy the correct source files from the installation directory to the directory of this your xcode project:
- All the FMX_*.pas files - All the FMX_*.res files - The tmsdefsios.inc file
The last step to take is to rename the tmsdefsios.inc file to tmsdefs.inc file in order to compile correctly. After opening the project in xcode, click the run button, which will automatically compile and run the project in the simulator. Of course you can select to run it on a real device as well.
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My First FireMonkey Component
Below is a sample that is useful to understand the design of a new FireMonkey component. These three code snippets will result in your first control which has a backgroundrectangle, a button, an edit, and an additional rectangle.
This component only loads the style file as a layout, and is static. You can click on the button and type in the edit field, but the component has no properties to interact with.
fmx.MyFirstControl.pas unit fmx.MyFirstControl; interface uses FMX.Types, Types, Classes; TMyFirstControl = class(TStyledControl) private public constructor Create(AOwner: TComponent); override; protected function GetClassName: String; virtual; function GetClassStyleName: String; virtual; function GetStyleObject: TControl; override; function LoadFromResource: TControl; end; procedure Register; implementation {$R fmx.myfirstcontrol.res} procedure Register; begin RegisterComponents(‘My First FireMonkey Control’, [TMyFirstControl]); end; function TMyFirstControl.GetClassName: String; begin Result := ClassName; end; constructor TMyFirstControl.Create(AOwner: TComponent); override; begin inherited; Width := 209; Height := 105; end; function TMyFirstControl.GetClassStyleName: String; begin Result := GetClassName + 'style'; Delete(Result, 1, 1); end; function TMyFirstControl.GetStyleObject: TControl; var obj: TControl; begin obj := inherited GetStyleObject; if not Assigned(obj) then begin // not found in default or custom style book, so create from resource obj := LoadFromResource; end; Result := obj; end; function TMyFirstControl.LoadFromResource: TControl; var S: TResourceStream; str: String; begin Result := nil; // create resource class name str := GetClassStyleName; if FindRCData(HInstance, str) then begin // load from RT_RCDATA resource type S := TResourceStream.Create(HInstance, str, RT_RCDATA); try Result := TControl(CreateObjectFromStream(nil, S)); finally S.Free; end; end; end; initialization RegisterFmxClasses([TMyFirstControl]); end.
fmx.myfirstcontrol.style object TRectangle StyleName = 'MyFirstControlStyle' Position.Point = '(184,248)' Width = 209.000000000000000000 Height = 105.000000000000000000 Fill.Kind = bkNone Stroke.Kind = bkNone object TRectangle StyleName = 'background' Align = alClient Width = 209.000000000000000000 Height = 105.000000000000000000 object TButton StyleName = 'Button1' Position.Point = '(10,20)' Width = 80.000000000000000000 Height = 22.000000000000000000 TabOrder = 0 Text = 'Button1' end object TEdit StyleName = 'Edit1' Position.Point = '(102,20)' Width = 100.000000000000000000 Height = 22.000000000000000000 TabOrder = 1 KeyboardType = vktDefault Password = False end object TRectangle StyleName = 'rectangleElement' Position.Point = '(11,48)' Width = 65.000000000000000000 Height = 49.000000000000000000 Fill.Color = xFFFF4B4B end end end
fmx.myfirstcontrol.rc MyFirstControlStyle RCDATA "fmx.myfirstcontrol.style"
rt := (FindStyleResource(‘rectangleElement’) as TRectangle); rt.RotationAngle := MyRotationAngleProperty; //sample below 45°
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FireMonkey Guidelines
More information on developing FireMonkey components and building / deploying on other platforms can be found on http://docwiki.embarcadero.com/RADStudio/en/FireMonkey_Components_Guide
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Updating the FireMonkey controls at runtime
To increase the performance, and to make sure all properties functions methods are executed and set, encapsulate every runtime update with a BeginUpdate and EndUpdate call.
var i: integer; begin TMSFMXTableView1.BeginUpdate; for i := 0 to 1000 do begin TMSFMXTableView1.Items.Add.Caption := 'item '+ inttostr(i); end; TMSFMXTableView1.EndUpdate; end;
var i: integer; begin TMSFMXGrid1.BeginUpdate; TMSFMXGrid1.ColumnWidths[2] := 100; TMSFMXGrid1.EndUpdate; end;
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How to create a new page at runtime
To create a new page at runtime the following code can be used:
var sp: TAdvSmoothPage; begin sp:= TAdvSmoothPage.Create(AdvSmoothPageSlider1); sp.PageSlider := AdvSmoothPageSlider1; sp.Header := 'Runtime created page'; end;
AdvSmoothPage.Free;
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How to know if a panel is Rolled In or Rolled Out
You can retrieve this via
AdvToolPanelTab.Panels[index].State = psOpened
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General tips
For optimum performance, grid.PageMode should be set to true. Depending on the TDataSet used, it might further improve performance to implement the OnGetRecordCount event.
The grid supports internal sorting, filtering, grouping, lookupbar as opposed to sorting, filtering, grouping performed on dataset level. When it is preferred to use the grids internal implementation as opposed to the dataset level implementation, set grid.PageMode = false.
Features like disjunct row selection, rearranging data (with goRowMoving = true in grid.Options or via drag & drop) also require that grid.PageMode = false
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Updating the tableview
Updating the list will be done whenever an item is added but to increase the performance, encapsulate every list update with a BeginUpdate and EndUpdate call.
var i: integer; begin TMSFMXTableView1.BeginUpdate; for i := 0 to 1000 do begin TMSFMXTableView1.Items.Add.Caption := 'item '+ inttostr(i); end; TMSFMXTableView1.EndUpdate; end;
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The scrollbar is only limited to three positions
This behavior is caused by the dataset. When grid.PageMode = true and DataSetType = dtNonSequenced the grid only displays a buffer of visible records, the grid has no information at all where this buffer is positioned in the database except that it is the first buffer, last buffer or not the first or last buffer. Hence, there are only 3 possible scrollbar positions.
When you set grid.PageMode = false, the grid loads & shows all records and can thus show an exact scrollbar position.