delphi安卓下热敏小票打印 源码

以下是Delphi安卓下热敏小票打印的一个示例源码，可以适用于一些常见型号的热敏打印机。需要注意的是，具体的打印指令格式和打印机型号有关，需要根据自己的打印机手册进行调整。

unit uPrintUtil;

interface

uses
  System.SysUtils, System.Classes, System.Types, System.IniFiles, FMX.Printer, FMX.Printer.Android,
  FMX.Types, FMX.Graphics, Androidapi.JNI.JavaTypes, Androidapi.JNI.GraphicsContentViewText,
  Androidapi.JNI.Net, Androidapi.JNI.Os, Androidapi.JNI.Provider, Androidapi.Helpers, Androidapi.JNI.Print,
  Androidapi.JNIBridge, FMX.Platform.Android, FMX.Forms, FMX.Dialogs;

type
  TPrintUtil = class(TObject)
  private
    class var FPrintManager: JPrintManager;
    class var FPrintAttributes: JPrintAttributes;
    class var FPrintDocumentAdapter: JPrintDocumentAdapter;
    class var FPrintJob: JPrintJob;
    class var FPrintContent: TStringList;
    class var FPrintIndex: Integer;
    class procedure DrawPage(canvas: JCanvas; pageWidth, pageHeight, pageIndex: Integer);
    class procedure StartPrintJob(printerName: string);
    class procedure EndPrintJob;
  public
    class procedure Print(printerName: string; content: TStringList);
  end;

implementation

{ TPrintUtil }

class procedure TPrintUtil.Print(printerName: string; content: TStringList);
begin
  FPrintContent := content;
  FPrintIndex := 0;
  StartPrintJob(printerName);
end;

class procedure TPrintUtil.DrawPage(canvas: JCanvas; pageWidth, pageHeight, pageIndex: Integer);
var
  paint: JPaint;
  rect: JRectF;
  text: string;
  lineHeight, x, y, i, j: Integer;
begin
  paint := TJPaint.Create;
  rect := TJRectF.Create(0, 0, pageWidth, pageHeight);
  lineHeight := Round(paint.getTextSize);
  x := 0;
  y := lineHeight;
  i := FPrintIndex;
  while (i < FPrintContent.Count) and (y + lineHeight < pageHeight) do
  begin
    text := FPrintContent[i];
    if Length(text) > 0 then
    begin
      if text[1] = #$1B then
      begin // 打印机控制命令
        if (Length(text) > 1) and (text[2] = #$21) then
        begin
          if (Length(text) > 3) and (text[3] = #1) then
            paint.setFakeBoldText(True)
          else
            paint.setFakeBoldText(False);
        end;
        if (Length(text) > 1) and (text[2] = #$21) then
        begin
          if (Length(text) > 3) and (text[3] = #8) then
            paint.setTextSize(lineHeight * 2)
          else
            paint.setTextSize(lineHeight);
        end;
      end
      else
        canvas.drawText(StringToJString(text), x, y, paint);
    end;
    Inc(y, lineHeight);
    Inc(i);
  end;
  FPrintIndex := i;
  if FPrintIndex < FPrintContent.Count then
    canvas.drawPage(rect);
end;

class procedure TPrintUtil.EndPrintJob;
begin
  FPrintAttributes := nil;
  FPrintDocumentAdapter := nil;
  FPrintJob := nil;
  FPrintManager := nil;
  FPrintContent := nil;
end;

class procedure TPrintUtil.StartPrintJob(printerName: string);
var
  printService: JPrintService;
begin
  FPrintManager := TJPrintManager.Wrap(TAndroidHelper.Context.getSystemService(TJContext.JavaClass.PRINT_SERVICE));
  if not Assigned(FPrintManager) then
  begin
    ShowMessage('打印服务不可用！');
    Exit;
  end;
  if not FPrintManager.isPrintServiceEnabled then
  begin
    ShowMessage('请先开启打印服务！');
    Exit;
  end;
  printService := FPrintManager.getPrintService;
  if not Assigned(printService) then
  begin
    ShowMessage('打印服务不可用！');
    Exit;
  end;
  FPrintAttributes := TJPrintAttributes.Wrap(TJPrintAttributes.JavaClass.builder.setMediaSize(TJPrintAttributes.JavaClass.MediaSize.ISO_A4)
    .setResolution(TJPrintAttributes.JavaClass.Resolution("300", "300", TJPrintAttributes.JavaClass.ResolutionDpi.DPI_INCH))
    .setColorMode(TJPrintAttributes.JavaClass.COLOR_MODE_COLOR)
    .setMinMargins(TJPrintAttributes.JavaClass.Margins.NO_MARGINS).build);
  FPrintDocumentAdapter := TJPrintDocumentAdapter.JavaClass.init(
    procedure (canvas: JCanvas; page: JInteger)
    begin
      DrawPage(canvas, FPrintAttributes.getMediaSize.getWidthMils, FPrintAttributes.getMediaSize.getHeightMils, page);
    end,
    procedure
    begin
      EndPrintJob;
    end);
  FPrintJob := printService.createPrintJob;
  if not Assigned(FPrintJob) then
  begin
    ShowMessage('打印失败！');
    EndPrintJob;
    Exit;
  end;
  FPrintJob.setPrintAttributes(FPrintAttributes);
  FPrintJob.setPrintJobName(StringToJString('打印任务'));
  if FPrintJob.isCancelled then
  begin
    EndPrintJob;
    Exit;
  end;
  FPrintJob.start;
  while not FPrintJob.isCompleted do
  begin
    if FPrintIndex < FPrintContent.Count then
      FPrintJob.print(FPrintDocumentAdapter, FPrintAttributes);
  end;
  EndPrintJob;
end;

end.

以上代码中，主要用到了Android打印机相关的API，将打印内容通过PrintDocumentAdapter逐页绘制到画布上，然后传递给PrintJob进行打印。在绘制的过程中，需要解析打印内容中的控制命令（例如设置字体大小、加粗等），并进行相应的处理。

在打印之前，需要先开启设备的打印服务，并确保打印机已连接到设备。具体使用方法可以参考Delphi官方文档和Android官方文档。