The Update ScrollBar Demo is the perfect way to see how Live Bindings can help keep your Edit control and Scrollbar control in sync. This cross-platform application has been built using a single codebase and UI, so it’s easy to use no matter what your preferred operating system might be. The Delphi-based app is fully compatible with Android, iOS, macOS, Windows, and Linux, making it incredibly versatile. With this demo, you’ll see how Live Bindings can make it easy to keep your information up-to-date and accurate – no matter where you are or what device you’re using. Take a look!
Download the full cross-platform scrollbar data binding demo source code on Github.
This demo is part of over 100 cross-platform demos with everything from camera demos to emoji demos and painting demos.
Table des matières
What is a scroll bar in software development?
A scroll bar is an element of a graphical user interface that allows a user to scroll through a document or web page. Scroll bars can be horizontal or vertical, and are typically located on the right side of a window or frame. In most cases, scroll bars are used to scroll vertically, but they can also be used to scroll horizontally in some cases. When a scroll bar is used to scroll horizontally, it is typically called a scroll bar. In software development, scroll bars are often used to scroll through long documents or web pages. They can also be used to scroll through images or other elements of a user interface.
Screenshot
What does the source code for the scrollbar demo look like?
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unit Unit1; interface uses System.SysUtils, System.Types, System.UITypes, System.Des classes, System.Variants, FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs, FireDAC.Stan.Intf, FireDAC.Stan.Option, FireDAC.Stan.Param, FireDAC.Stan.Error, FireDAC.DatS, FireDAC.Phys.Intf, FireDAC.DApt.Intf, FireDAC.Stan.StorageBin, Data.Bind.EngExt, Fmx.Bind.DBEngExt, System.Rtti, System.Bindings.Outputs, Fmx.Bind.Editors, FireDAC.Stan.StorageJSON, Data.Bind.Composants, Data.Bind.DBScope, Data.DB, FireDAC.Comp.DataSet, FireDAC.Comp.Client, FMX.StdCtrls, FMX.Effects, FMX.Controls.Presentation, FMX.Edit; type TForm1 = classe(TForm) MaterialOxfordBlueSB: TStyleBook; ToolBar1: TToolBar; ShadowEffect4: TShadowEffect; Label1: TLabel; Label2: TLabel; <strong> ScrollBar1: TScrollBar; FDMemTable1: TFDMemTable; BindSourceDB1: TBindSourceDB; BindingsList1: TBindingsList; FDStanStorageJSONLink1: TFDStanStorageJSONLink; Edit1: TEdit; LinkControlToField1: TLinkControlToField; LinkPropertyToFieldText: TLinkPropertyToField; procedure ScrollBar1Change(Sender: TObject); procedure Edit1Validate(Sender: TObject; var Text: string);</strong> private { Private declarations } public { Public declarations } end; var Form1: TForm1; implementation {$R *.fmx} <strong>procedure TForm1.Edit1Validate(Sender: TObject; var Text: string); var LValue: Single; commencer LValue := Text.ToSingle; if LValue<>ScrollBar1.Value then ScrollBar1.Value := Text.ToSingle; end; procedure TForm1.ScrollBar1Change(Sender: TObject); commencer Edit1.Text := ScrollBar1.Value.ToString; TLinkObservers.ControlChanged(Edit1); end;</strong> end. |
What does the data bindings look like for the demo?
What does the Form object control code look like?
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object BindSourceDB1: TBindSourceDB DataSet = FDMemTable1 ScopeMappings = <> Left = 144 Top = 224 end object BindingsList1: TBindingsList Methods = <> OutputConverters = <> Left = 20 Top = 5 object LinkControlToField1: TLinkControlToField Category = 'Quick Bindings' DataSource = BindSourceDB1 FieldName = 'Value' Control = Edit1 Track = False end object LinkPropertyToFieldText: TLinkPropertyToField Category = 'Quick Bindings' DataSource = BindSourceDB1 FieldName = 'Value' Component = Label2 ComponentProperty = 'Text' end end object FDStanStorageJSONLink1: TFDStanStorageJSONLink Left = 168 Top = 368 end |
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