如何使用FireMonkey(多平台)截取屏幕截图

procedure TMyForm.OnPaint(Sender: TObject);
begin
  if (Sender is TImage) then
  begin
    TImage(Sender).Canvas.Brush.Color := clWhite;
    TImage(Sender).Canvas.Font.Color := clBlack;
    TImage(Sender).Canvas.Font.Size := 14;
    TImage(Sender).Canvas.TextOut(10, 10, 'My Application');
  end
  else
    inherited;
end;

unit ScreenCapture;

interface

uses
  SysUtils, Windows, Forms, Classes, Graphics, Controls, StdCtrls, ExtCtrls,
  FMX, FMX.Platform, FMX.Controls, FMX.Forms, FMX.Dialogs, FMX.StdCtrls;

type
  TScreenCapture = class(TComponent)
  private
    { Private declarations }
  public
    { Public declarations }
    procedure CaptureScreen();
  end;

var
  ScreenCapture: TScreenCapture;

implementation

{$R *.fmx}

procedure TScreenCapture.CaptureScreen();
var
  Bitmap: TBitmap;
  Str: string;
begin
  // 获取当前屏幕截图
  Bitmap := TBitmap.Create;
  try
    Bitmap.SetSize(Width, Height);
    Bitmap.Canvas.Draw(0, 0, Bitmap);

    // 将截图转换为 24 位真彩色位图
    Bitmap.SetSize(Width, Height, 24);
    Str := Format('Image-%d.png', [Count]);
    Bitmap.SaveToPNG(Str);

    // 显示截图
    Image1.Picture.Assign(Bitmap);
  finally
    Bitmap.Free;
  end;
end;

end.

procedure TFrmMain.FormPaint(Sender: TObject);
begin
  if (Sender is TImage) then
  begin
    TImage(Sender).Canvas.Brush.Color := clWhite;
    TImage(Sender).Canvas.Font.Color := clBlack;
    TImage(Sender).Canvas.Font.Size := 14;
    TImage(Sender).Canvas.TextOut(10, 10, 'My Application');
  end
  else
    inherited;
end;