delphi安卓下热敏打印源码

以下是一个简单的Delphi安卓下热敏打印的示例代码，需要先引入Java类库，具体实现方式可参考前面的说明。

unit AndroidPrint;

interface

uses
  System.SysUtils, System.Classes, Androidapi.JNI.GraphicsContentViewText,
  Androidapi.JNI.JavaTypes;

type
  TAndroidPrint = class
  private
    FContext: JContext;
    FPrinter: JPrinter; // 打印机SDK的Java类库
    FBuffer: TBytes;
    function GetPrinterStatus: Boolean;
  public
    constructor Create(AContext: JContext);
    destructor Destroy; override;
    procedure PrintText(AText: string);
    procedure LineFeed;
    procedure CutPaper;
    procedure SetGrayLevel(ALevel: Byte);
    property PrinterStatus: Boolean read GetPrinterStatus;
  end;

implementation

const
  BUFFER_SIZE = 256; // 缓冲区大小

constructor TAndroidPrint.Create(AContext: JContext);
begin
  FContext := AContext;
  FPrinter := TJPrinter.JavaClass.init(FContext); // 初始化打印机SDK类库
  SetLength(FBuffer, BUFFER_SIZE);
end;

destructor TAndroidPrint.Destroy;
begin
  FPrinter := nil;
  inherited;
end;

procedure TAndroidPrint.PrintText(AText: string);
var
  Bytes: TBytes;
  JavaBytes: TJavaArray<Byte>;
begin
  Bytes := TEncoding.UTF8.GetBytes(AText);
  if Length(Bytes) > BUFFER_SIZE then
    raise Exception.Create('Print text too long');

  Move(Bytes[0], FBuffer[0], Length(Bytes));
  JavaBytes := TJavaArray<Byte>.Create(FBuffer);
  FPrinter.printText(JavaBytes); // 调用打印机SDK类库的打印方法
end;

procedure TAndroidPrint.LineFeed;
begin
  FPrinter.lineFeed;
end;

procedure TAndroidPrint.CutPaper;
begin
  FPrinter.cutPaper;
end;

procedure TAndroidPrint.SetGrayLevel(ALevel: Byte);
begin
  FPrinter.setGrayLevel(ALevel);
end;

function TAndroidPrint.GetPrinterStatus: Boolean;
begin
  Result := FPrinter.getPrinterStatus;
end;

end.

使用方法：

procedure TForm1.Button1Click(Sender: TObject);
var
  AndroidPrint: TAndroidPrint;
begin
  AndroidPrint := TAndroidPrint.Create(Self);
  try
    AndroidPrint.PrintText('这是一张小票'#10#13);
    AndroidPrint.LineFeed;
    AndroidPrint.CutPaper;
  finally
    AndroidPrint.Free;
  end;
end;

需要注意的是，以上代码仅供参考，实际使用时需要根据打印机SDK的Java类库进行相应的调用。