Delphi XE5 Android 调用 Google ZXing

{

   Google ZXing Call demo



   Delphi Version: Delphi XE5 Version 19.0.13476.4176



   By: flcop([email protected]) 

}



unit UMain;



interface



uses

  System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,

  FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs, FMX.StdCtrls,

  FMX.Layouts, FMX.Memo,



  System.Rtti, 

  FMX.Helpers.Android,

  Androidapi.JNI.Net,

  Androidapi.JNI.GraphicsContentViewText,

  Androidapi.JNI.JavaTypes,

  FMX.platform,

  FMX.Platform.Android;



type

  TFrmMain = class(TForm)

    Memo1: TMemo;

    Button1: TButton;

    Button2: TButton;

    Button3: TButton;

    PanelOpt: TPanel;

    Panel2: TPanel;

    SBTitle: TSpeedButton;

    procedure Button1Click(Sender: TObject);

    procedure FormCreate(Sender: TObject);

    procedure SBTitleClick(Sender: TObject);

  private

    { Private declarations }

    FClipboardService: IFMXClipboardService;

    FClipboardValue: TValue;

    FZXingCalled: Boolean;

    procedure CallZXing(const ACodeMode: string);

    function IsIntentCallable(const AIntent: JIntent): Boolean;

    function GetZXingIntent: JIntent;

    procedure ClipboardSave;

    procedure ClipboardBack;

    procedure ShowInfo(const AInfo: string);

    function HandleAppEvent(AAppEvent: TApplicationEvent; AContext: TObject): Boolean;

    procedure CheckEnvironment;

    procedure OpenURL(const AURL: string);

  public

    { Public declarations }

  end;



var

  FrmMain: TFrmMain;



implementation



{$R *.fmx}



const

  CodeModes: array[0..2] of string = ('PRODUCT_MODE', 'QR_CODE_MODE', 'SCAN_MODE');



procedure TFrmMain.Button1Click(Sender: TObject);

begin

  // 0, 1, 2

  CallZXing(CodeModes[TButton(Sender).Tag]);

end;



procedure TFrmMain.CallZXing(const ACodeMode: string);

var

  LIntent: JIntent;

begin

  ClipboardSave;

  FClipboardService.SetClipboard('');

  LIntent := GetZXingIntent();

  LIntent.putExtra(StringToJString('SCAN_MODE'), StringToJString(ACodeMode));

  SharedActivity.startActivityForResult(LIntent, 0);

  FZXingCalled := True;

end;



procedure TFrmMain.CheckEnvironment;

var

  LFMXApplicationEventService: IFMXApplicationEventService;

  LIsZXingCallable: Boolean;

  LStr: string;

begin

  if TPlatformServices.Current.SupportsPlatformService(IFMXApplicationEventService,

       IInterface(LFMXApplicationEventService)) then

    LFMXApplicationEventService.SetApplicationEventHandler(HandleAppEvent)

  else

    LStr := '调用失败,不支持IFMXApplicationEventService!';



  if not TPlatformServices.Current.SupportsPlatformService(IFMXClipboardService,

       IInterface(FClipboardService)) then

    LStr := LStr + sLineBreak + '调用失败, 不支持IFMXClipboardService!';



  LIsZXingCallable := IsIntentCallable(GetZXingIntent);

  if not LIsZXingCallable then

  begin

    SBTitle.Text := '点我去ZXing下载页...';

    SBTitle.OnClick := SBTitleClick;

    LStr := LStr + sLineBreak + '未发现ZXing, 请安装ZXing后重新启动本程序';

  end else

    SBTitle.Text := 'Google ZXing Call';



  ShowInfo(LStr.Trim);



  PanelOpt.Enabled := Assigned(LFMXApplicationEventService) and

                      Assigned(FClipboardService) and LIsZXingCallable;

end;



procedure TFrmMain.ClipboardBack;

begin

  FClipboardService.SetClipboard(FClipboardValue);

end;



procedure TFrmMain.ClipboardSave;

begin

  FClipboardValue := FClipboardService.GetClipboard;

end;



procedure TFrmMain.FormCreate(Sender: TObject);

begin

  CheckEnvironment;

end;



function TFrmMain.GetZXingIntent: JIntent;

const

  GOOGLE_ZXING = 'com.google.zxing.client.android.SCAN';

  GOOGLE_ZXING_PACKAGE = 'com.google.zxing.client.android';

begin

  Result := TJIntent.JavaClass.init(StringToJString(GOOGLE_ZXING));

  Result.setPackage(StringToJString(GOOGLE_ZXING_PACKAGE));

end;



function TFrmMain.HandleAppEvent(AAppEvent: TApplicationEvent;

  AContext: TObject): Boolean;

var

  LResult: string;

begin

  if FZXingCalled and (AAppEvent = TApplicationEvent.aeBecameActive) then

  begin

    LResult := FClipboardService.GetClipboard.ToString;

    if LResult.IsEmpty then

      ShowInfo('扫描取消')

    else

      ShowInfo(LResult);

    ClipboardBack;

    FZXingCalled := False;

  end;

  Result := True;

end;



function TFrmMain.IsIntentCallable(const AIntent: JIntent): Boolean;

var

  LJPackageManager: JPackageManager;

begin

  Result := False;

  if Assigned(AIntent) then

  begin

    LJPackageManager := SharedActivityContext.getPackageManager;

    Result := LJPackageManager.queryIntentActivities(AIntent,

      TJPackageManager.JavaClass.MATCH_DEFAULT_ONLY).size <> 0;

  end;

end;



procedure TFrmMain.OpenURL(const AURL: string);

var

  LIntent: JIntent;

begin

  LIntent := TJIntent.JavaClass.init(TJIntent.JavaClass.ACTION_VIEW, 

    TJnet_Uri.JavaClass.parse(StringToJString(AURL)));

  SharedActivity.startActivity(LIntent);

end;



procedure TFrmMain.SBTitleClick(Sender: TObject);

begin

  OpenURL('http://code.google.com/p/zxing/downloads/list');

end;



procedure TFrmMain.ShowInfo(const AInfo: string);

begin

  Memo1.Text := AInfo;

end;



end.