Android Studio-打印管理器不起作用。从不显示文件

Question

好吧，我有一个应用程序待命，并且在5到6个月后，Print Manager的一部分停止工作。

这很奇怪，因为加载了PrintDocumentAdapter（在构造函数的生成器中输入，不知道英文的确切名称），但是从不进入onStart，onLayout ...并且不显示任何错误。这是非常无奈的。

电话是：

PrintManager printManager = (PrintManager) this
                    .getSystemService(Context.PRINT_SERVICE);

String jobName = this.getString(R.string.app_name) + " Document";

printManager.print(jobName, new AlbaranPrintDocumentAdapter(this, this, getResources(), granja, lesiones,
                    bmFirma, bmSanasVSLesion, bmPorcentajeLesiones, sesion), null);

“打印管理器”类就是这样的（我将示例中的方法的所有内容都剪掉了，但这不是必需的。无论如何，代码永远不会输入到方法中）：

package com.example.somename.somename.activities;

import android.content.Context;
import android.content.SharedPreferences;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Typeface;
import android.graphics.pdf.PdfDocument;
import android.os.Build;
import android.os.Bundle;
import android.os.CancellationSignal;
import android.os.ParcelFileDescriptor;
import android.print.PageRange;
import android.print.PrintAttributes;
import android.print.PrintDocumentAdapter;
import android.print.PrintDocumentInfo;
import android.print.pdf.PrintedPdfDocument;
import android.support.annotation.RequiresApi;

import android.util.Log;
import android.graphics.pdf.PdfDocument.PageInfo;

import com.example.somename.somename.R;
import com.example.somename.somename.pojos.Empresas;
import com.example.somename.somename.pojos.Granja;
import com.example.somename.somename.pojos.Intervencion;
import com.example.somename.somename.pojos.Lesion;
import com.example.somename.somename.pojos.Revision;
import com.example.somename.somename.pojos.Sesion;
import com.example.somename.somename.util.GuardarImagen;

import java.io.FileOutputStream;
import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

@RequiresApi(api = Build.VERSION_CODES.KITKAT)
public class AlbaranPrintDocumentAdapter extends PrintDocumentAdapter {

    }

    public AlbaranPrintDocumentAdapter(E02_GraficasActivity graficasActivity, Context context, Resources res, Granja granja, Lesion[] lesiones, Bitmap bmFirma,
                                       Bitmap bmSanasVSLesion, Bitmap bmPorcentajeLesiones, Sesion sesion) {
        Log.v("Lugar", "AlbaranPrintDocumentAdapter");
        this.graficasActivity = graficasActivity;
        this.context = context;
        this.res = res;
        this.granja = granja;
        this.lesiones = lesiones;
        this.bmFirma = bmFirma;
        this.bmSanasVSLesion = bmSanasVSLesion;
        this.bmPorcentajeLesiones = bmPorcentajeLesiones;
        this.sesion = sesion;
    }

    @Override
    public void onStart() {
        Log.v("Lugar", "AlbaranPrintDocumentAdapter > OnStart");
    }

    @Override
    public void onLayout(PrintAttributes oldAttributes,
                         PrintAttributes newAttributes,
                         CancellationSignal cancellationSignal,
                         LayoutResultCallback callback,
                         Bundle metadata) {

        Log.v("Lugar", "AlbaranPrintDocumentAdapter > OnLayout");


    }

    private int calculatePages() {
        Log.v("Lugar", "AlbaranPrintDocumentAdapter > calculatePages");
        //int count = Math.round(lesiones.length / 7);
        //Log.v("ADRI", "calculatePages formula = (" + lesiones.length + " + 10 - 1) / 10");
        int count = 0;
        if (lesiones.length <= 22) {
            count = 1;
        } else if (lesiones.length <= 54) {
            count = 2;
        } else if (lesiones.length <= 86) {
            count = 3;
        } else if (lesiones.length <= 118) {
            count = 4;
        } else if (lesiones.length <= 150) {
            count = 5;
        } else if (lesiones.length <= 182) {
            count = 6;
        } else if (lesiones.length <= 214) {
            count = 7;
        } else if (lesiones.length <= 246) {
            count = 8;
        } else if (lesiones.length <= 278) {
            count = 9;
        }
        return count;
    }

    @Override
    public void onWrite(final PageRange[] pageRanges,
                        final ParcelFileDescriptor destination,
                        final CancellationSignal cancellationSignal,
                        final WriteResultCallback callback) {

        Log.v("Lugar", "AlbaranPrintDocumentAdapter > onWrite");


        callback.onWriteFinished(pageRanges);
    }

    private boolean pageInRange(PageRange[] pageRanges, int page) {
        Log.v("Lugar", "AlbaranPrintDocumentAdapter > pageInRange");
        for (int i = 0; i < pageRanges.length; i++) {
            if ((page >= pageRanges[i].getStart()) &&
                    (page <= pageRanges[i].getEnd()))
                return true;
        }
        return false;
    }

    private void drawPage(PdfDocument.Page page,
                          int pagenumber) {
        Log.v("Lugar", "AlbaranPrintDocumentAdapter > drawPage");

    }


    public void calcularTotales() {

    }

}