但是,当我将示例项目连接到打印机时,同样有效.

private boolean runPrintReceiptSequence() {
    if (!initializeObject()) {
        return false;
    }

    if (!createReceiptData()) {
        finalizeObject();
        return false;
    }

    if (!printData()) {
        finalizeObject();
        return false;
    }

    return true;
}

private boolean initializeObject() {
    try {

        final SpnModelsItem spnModel = new SpnModelsItem("TM-T82 Series",Printer.TM_T82);
        final SpnModelsItem spnLang = new SpnModelsItem("ANK",Printer.MODEL_ANK);

        mPrinter = new Printer(spnModel.getModelConstant(),spnLang.getModelConstant(),this);
    }
    catch (Exception e) {
        Log.e("Printer",e.toString());
        return false;
    }

    mPrinter.setReceiveEventListener(this);


    return true;
}

private boolean createReceiptData() {
    String method = "";
    Bitmap logoData = BitmapFactory.decodeResource(getResources(),R.drawable.logo_saltnpepper);
    StringBuilder textData = new StringBuilder();
    final int barcodeWidth = 2;
    final int barcodeHeight = 100;
    Date currentDate = new Date();
    info.saltnpepper.ordersmart2.MenuItem currItem = null;

    double price = 0;
    double total = 0;
    int totalQty =0;

    if (mPrinter == null) {
        return false;
    }

    try {
        method = "addTextAlign";
        mPrinter.addTextAlign(Printer.ALIGN_CENTER);

        method = "addImage";
        mPrinter.addImage(logoData,logoData.getWidth(),logoData.getHeight(),Printer.COLOR_1,Printer.MODE_MONO,Printer.HALFTONE_DITHER,Printer.PARAM_DEFAULT,Printer.COMPRESS_AUTO);

        method = "addFeedLine";
        mPrinter.addFeedLine(1);
        textData.append("SALT-N-PEPPER\n");
        //textData.append("STORE DIRECTOR – John Smith\n");
        textData.append("\n");
        textData.append((new SimpleDateFormat("dd/MM/yy HH:mm:ss")).format(currentDate).toString() + "\n");
        //textData.append("ST# 21 OP# 001 TE# 01 TR# 747\n");
        textData.append("------------------------------\n");
        method = "addText";
        mPrinter.addText(textData.toString());
        textData.delete(0,textData.length());
        if(alFinalOrder != null)
        {
            for(int i=0; i < alFinalOrder.size(); i++)
            {
                currItem = alFinalOrder.get(i);
                textData.append(currItem.getName()+"  "+currItem.getQty()+"  "+currItem.getPrice()+"\n");

                //calculate total quantity
                totalQty = totalQty + currItem.getQty();

                //calculate price
                double dPrice = currItem.getQty()*Double.parseDouble(currItem.getPrice().substring(1));
                total = total + dPrice;
                total = Math.round(total*100.0)/100.0;

            }
        }
        textData.append("------------------------------\n");
        method = "addText";
        mPrinter.addText(textData.toString());
        textData.delete(0,textData.length());

        textData.append("TOTAL                   "+"\n");
        textData.append("TAX                     "+"\n");
        method = "addText";
        mPrinter.addText(textData.toString());
        textData.delete(0,textData.length());

mPrinter.addFeedLine(2);

method = "addBarcode";
        mPrinter.addBarcode("01209457",Printer.BARCODE_CODE39,Printer.HRI_BELOW,Printer.FONT_A,barcodeWidth,barcodeHeight);

        method = "addCut";
        mPrinter.addCut(Printer.CUT_Feed);
    }
    catch (Exception e) {
        //ShowMsg.showException(e,method,mContext);
        return false;
    }

    textData = null;

    return true;
}

private boolean printData() {
    if (mPrinter == null) {
        return false;
    }

    if (!connectPrinter()) {
        return false;
    }

    PrinterStatusInfo status = mPrinter.getStatus();

    dispPrinterWarnings(status);

    if (!isPrintable(status)) {
        Log.e("Printer","Is not printable");
        try {
            mPrinter.disconnect();
        }
        catch (Exception ex) {
            // Do nothing
        }
        return false;
    }

    try {
        mPrinter.sendData(Printer.PARAM_DEFAULT);
    }
    catch (Exception e) {
        Log.e("Printer",e.getMessage());
        try {
            mPrinter.disconnect();
        }
        catch (Exception ex) {
            // Do nothing
        }
        return false;
    }

    return true;
}

private boolean connectPrinter() {
    boolean isBeginTransaction = false;

    if (mPrinter == null) {
        return false;
    }

    try {
        mPrinter.connect("TCP:"+mIP,Printer.PARAM_DEFAULT);
    }
    catch (Epos2Exception e) {
        //ShowMsg.showException(e,"connect",this);
        if(e.getErrorStatus() == Epos2Exception.ERR_CONNECT)
        {
            Log.e("testing","error connect");
        }
        if(e.getErrorStatus() == Epos2Exception.ERR_ALREADY_OPENED)
        {
            Log.e("testing","already open");
        }
        if(e.getErrorStatus() == Epos2Exception.ERR_ALREADY_USED)
        {
            Log.e("testing","already used");
        }
        if(e.getErrorStatus() == Epos2Exception.ERR_Box_CLIENT_OVER)
        {
            Log.e("testing","Box client over");
        }
        if(e.getErrorStatus() == Epos2Exception.ERR_Box_COUNT_OVER)
        {
            Log.e("testing","count over");
        }
        if(e.getErrorStatus() == Epos2Exception.ERR_DISCONNECT)
        {
            Log.e("testing","disconnect");
        }
        if(e.getErrorStatus() == Epos2Exception.ERR_FAILURE)
        {
            Log.e("testing","failure");
        }
        if(e.getErrorStatus() == Epos2Exception.ERR_ILLEGAL)
        {
            Log.e("testing","illegal");
        }
        if(e.getErrorStatus() == Epos2Exception.ERR_IN_USE)
        {
            Log.e("testing","in use");
        }
        if(e.getErrorStatus() == Epos2Exception.ERR_MEMORY)
        {
            Log.e("testing","memory");
        }
        return false;
    }

    try {
        mPrinter.beginTransaction();
        isBeginTransaction = true;
    }
    catch (Exception e) {
        Log.e("Printer",e.toString ());
    }

    if (isBeginTransaction == false) {
        try {
            mPrinter.disconnect();
        }
        catch (Epos2Exception e) {
            // Do nothing
            return false;
        }
    }

    return true;
}

它总是在connectprinter函数内的printer.connect上给我异常ERR_CONNECT.

我究竟做错了什么？

此代码适用于示例应用程序.
P.S：我在连接示例应用程序之前尝试连接此应用程序,以检查示例应用程序是否保持连接,并且不允许其他应用程序连接,但事实并非如此.爱普生帮助无法提供任何进一步的帮助.

我的AndroidManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="xyz"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
    android:minSdkVersion="21"
    android:targetSdkVersion="21" />

<application
    android:allowBackup="true"
    android:icon="@drawable/icon"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name=".MainActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity android:name=".MenuActivity" >
    </activity>
    <activity
        android:name=".SaltnPepperActivity"
        android:label="@string/title_activity_saltn_pepper" >
    </activity>
            <activity
        android:name=".FinalOrder"
         ></activity>
                <activity
        android:name=".ZinVietActivity"
         >
    </activity>
     <activity
        android:name="com.epson.epos2_printer.DiscoverActivity"
         ></activity>

</application>