Java tutorial
/* * Copyright (C) 2016 Ferid Cafer * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.ferid.app.classroom.statistics; import android.content.ActivityNotFoundException; import android.content.Context; import android.content.Intent; import android.net.Uri; import android.os.AsyncTask; import android.os.Bundle; import android.os.Handler; import android.support.annotation.Nullable; import android.support.design.widget.Snackbar; import android.support.v4.app.Fragment; import android.support.v4.widget.SwipeRefreshLayout; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.TextView; import com.ferid.app.classroom.R; import com.ferid.app.classroom.adapters.OperateClassroomsAdapter; import com.ferid.app.classroom.database.DatabaseManager; import com.ferid.app.classroom.listeners.AdapterClickListener; import com.ferid.app.classroom.model.Attendance; import com.ferid.app.classroom.model.Classroom; import com.ferid.app.classroom.utility.DirectoryUtility; import com.ferid.app.classroom.utility.ExcelStyleManager; import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.apache.poi.ss.usermodel.Cell; import org.apache.poi.ss.usermodel.Row; import org.apache.poi.ss.usermodel.Sheet; import org.apache.poi.ss.usermodel.Workbook; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.util.ArrayList; import java.util.HashMap; /** * Created by ferid.cafer on 4/20/2015.<br /> * Prepares statistical data and excel file. */ public class StatisticsFragment extends Fragment { private Context context; private SwipeRefreshLayout swipeRefreshLayout; private RecyclerView list; private ArrayList<Classroom> classroomArrayList = new ArrayList<>(); private OperateClassroomsAdapter classroomAdapter; private TextView emptyText; //empty list view text //excel private final String FILE_NAME = "attendances.xls"; private ArrayList<Attendance> attendanceArrayList = new ArrayList<>(); public StatisticsFragment() { } public static StatisticsFragment newInstance() { StatisticsFragment statisticsFragment = new StatisticsFragment(); return statisticsFragment; } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // retain this fragment setRetainInstance(true); } @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.refreshable_list, container, false); context = rootView.getContext(); list = (RecyclerView) rootView.findViewById(R.id.list); classroomAdapter = new OperateClassroomsAdapter(classroomArrayList); list.setAdapter(classroomAdapter); list.setLayoutManager(new LinearLayoutManager(context)); list.setHasFixedSize(true); emptyText = (TextView) rootView.findViewById(R.id.emptyText); swipeRefreshLayout = (SwipeRefreshLayout) rootView.findViewById(R.id.swipeRefreshLayout); swipeRefreshLayout.setColorSchemeResources(android.R.color.holo_blue_bright, android.R.color.holo_green_light, android.R.color.holo_orange_light, android.R.color.holo_red_light); swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() { @Override public void onRefresh() { new SelectClassrooms().execute(); } }); addAdapterClickListener(); new SelectClassrooms().execute(); return rootView; } /** * Set empty list text */ private void setEmptyText() { if (emptyText != null) { if (classroomArrayList.isEmpty()) { emptyText.setVisibility(View.VISIBLE); } else { emptyText.setVisibility(View.GONE); } } } /** * List item click event */ private void addAdapterClickListener() { classroomAdapter.setAdapterClickListener(new AdapterClickListener() { @Override public void OnItemClick(int position) { if (classroomArrayList != null && classroomArrayList.size() > position) { Intent intent = new Intent(context, StatisticalListActivity.class); intent.putExtra("classroom", classroomArrayList.get(position)); startActivity(intent); getActivity().overridePendingTransition(R.anim.move_in_from_bottom, R.anim.stand_still); } } }); } /** * Select classrooms from DB */ private class SelectClassrooms extends AsyncTask<Void, Void, ArrayList<Classroom>> { @Override protected void onPreExecute() { swipeRefreshLayout.setRefreshing(true); } @Override protected ArrayList<Classroom> doInBackground(Void... params) { DatabaseManager databaseManager = new DatabaseManager(context); ArrayList<Classroom> tmpList = databaseManager.selectClassroomsWithStudentNumber(); return tmpList; } @Override protected void onPostExecute(ArrayList<Classroom> tmpList) { swipeRefreshLayout.setRefreshing(false); classroomArrayList.clear(); if (tmpList != null) { classroomArrayList.addAll(tmpList); classroomAdapter.notifyDataSetChanged(); setEmptyText(); } } } /** * Select all for excel */ private class SelectForExcel extends AsyncTask<Void, Void, ArrayList<Attendance>> { @Override protected void onPreExecute() { swipeRefreshLayout.setRefreshing(true); } @Override protected ArrayList<Attendance> doInBackground(Void... params) { DatabaseManager databaseManager = new DatabaseManager(context); ArrayList<Attendance> tmpList = databaseManager.selectAllAttendances(); return tmpList; } @Override protected void onPostExecute(ArrayList<Attendance> tmpList) { attendanceArrayList.clear(); if (tmpList != null && !tmpList.isEmpty()) { attendanceArrayList.addAll(tmpList); new Handler().post(new Runnable() { @Override public void run() { convertToExcel(); } }); } else { swipeRefreshLayout.setRefreshing(false); excelFileError(getString(R.string.takeAttendanceBeforeExcel)); } } } public void getDataForExcel() { new SelectForExcel().execute(); } /** * Converts all attendances into excel format */ private void convertToExcel() { //create workbook Workbook wb = new HSSFWorkbook(); for (Classroom classroom : classroomArrayList) { //each sheet //create sheet Sheet sheet = wb.createSheet(classroom.getName()); //header HashMap<String, Integer> date_column_map = new HashMap<>(); ArrayList<String> dates = new ArrayList<>(); int rowNumber = 0; int colNumber = 1; Row row = sheet.createRow(rowNumber); //dates columns for (Attendance attendance : attendanceArrayList) { if (classroom.getId() == attendance.getClassroomId() && !dates.contains(attendance.getDateTime())) { Cell cellDate = row.createCell(colNumber); cellDate.setCellStyle(ExcelStyleManager.getHeaderCellStyle(wb)); cellDate.setCellValue(attendance.getDateTime()); dates.add(attendance.getDateTime()); date_column_map.put(attendance.getDateTime(), colNumber); //set width of the dates columns sheet.setColumnWidth(colNumber, getResources().getInteger(R.integer.statistics_excel_column_width_dates)); colNumber++; } } //set width of the students column //it is always the first column sheet.setColumnWidth(0, getResources().getInteger(R.integer.statistics_excel_column_width_students)); //students list at the left column HashMap<Integer, Integer> student_row_map = new HashMap<>(); ArrayList<Integer> studentIds = new ArrayList<>(); rowNumber = 1; for (Attendance attendance : attendanceArrayList) { if (classroom.getId() == attendance.getClassroomId() && !studentIds.contains(attendance.getStudentId())) { //another student row = sheet.createRow(rowNumber); Cell cellStudent = row.createCell(0); cellStudent.setCellStyle(ExcelStyleManager.getHeaderCellStyle(wb)); cellStudent.setCellValue(attendance.getStudentName()); studentIds.add(attendance.getStudentId()); student_row_map.put(attendance.getStudentId(), rowNumber); rowNumber++; } } //now get column number from date columns //and get row number from student rows //match row-column pair and print into cell for (Attendance attendance : attendanceArrayList) { if (classroom.getId() == attendance.getClassroomId()) { rowNumber = student_row_map.get(attendance.getStudentId()); colNumber = date_column_map.get(attendance.getDateTime()); row = sheet.getRow(rowNumber); Cell cellPresence = row.createCell(colNumber); cellPresence.setCellStyle(ExcelStyleManager.getContentCellStyle(wb)); cellPresence.setCellValue(attendance.getPresent()); } } } if (classroomArrayList.size() > 0) { writeIntoFile(wb); } swipeRefreshLayout.setRefreshing(false); } /** * Write into an excel file * @param wb */ private void writeIntoFile(Workbook wb) { boolean isFileOperationSuccessful = true; FileOutputStream fileOut = null; if (DirectoryUtility.isExternalStorageMounted()) { DirectoryUtility.createDirectory(); try { fileOut = new FileOutputStream(DirectoryUtility.getPathFolder() + FILE_NAME); wb.write(fileOut); } catch (IOException e) { isFileOperationSuccessful = false; } finally { if (fileOut != null) { try { fileOut.flush(); fileOut.close(); } catch (IOException e) { isFileOperationSuccessful = false; } } } //if file is successfully created and closed //open file, otherwise display error if (isFileOperationSuccessful) { openExcelFile(); } else { excelFileError(getString(R.string.excelError)); } } else { //external storage is not available excelFileError(getString(R.string.mountExternalStorage)); } } /** * Open and show the created excel file */ private void openExcelFile() { if (DirectoryUtility.isExternalStorageMounted()) { File file = new File(DirectoryUtility.getPathFolder() + FILE_NAME); if (file.exists()) { try { Intent intent = new Intent(Intent.ACTION_VIEW); intent.setDataAndType(Uri.fromFile(file), "application/vnd.ms-excel"); intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); startActivity(intent); } catch (ActivityNotFoundException e) { //if excel reader not found, ask to download one (Google Sheets) Snackbar.make(list, getString(R.string.excelReaderNotFound), Snackbar.LENGTH_LONG) .setAction(getString(R.string.download), new View.OnClickListener() { @Override public void onClick(View v) { final String appPackageName = "com.google.android.apps.docs.editors.sheets"; try { startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("market://details?id=" + appPackageName))); } catch (android.content.ActivityNotFoundException anfe) { startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("https://play.google.com/store/apps/details?id=" + appPackageName))); } } }).show(); } } else { excelFileError(getString(R.string.excelError)); } } else { excelFileError(getString(R.string.mountExternalStorage)); } } /** * Excel related error * @param errorMessage String */ private void excelFileError(String errorMessage) { Snackbar.make(list, errorMessage, Snackbar.LENGTH_LONG).show(); } }