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.edit; import android.app.ProgressDialog; import android.content.ActivityNotFoundException; import android.content.Context; import android.content.Intent; import android.content.pm.PackageManager; import android.os.AsyncTask; import android.os.Bundle; import android.os.Environment; import android.os.Handler; import android.support.design.widget.FloatingActionButton; import android.support.design.widget.Snackbar; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.Toolbar; import android.text.TextUtils; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.inputmethod.InputMethodManager; import android.widget.TextView; import com.ferid.app.classroom.R; import com.ferid.app.classroom.adapters.EditStudentsAdapter; import com.ferid.app.classroom.database.DatabaseManager; import com.ferid.app.classroom.enums.StudentPopup; import com.ferid.app.classroom.listeners.OnAlertClick; import com.ferid.app.classroom.listeners.PermissionGrantListener; import com.ferid.app.classroom.listeners.PopupClickListener; import com.ferid.app.classroom.listeners.PromptListener; import com.ferid.app.classroom.material_dialog.CustomAlertDialog; import com.ferid.app.classroom.material_dialog.PromptDialog; import com.ferid.app.classroom.model.Classroom; import com.ferid.app.classroom.model.Student; import com.ferid.app.classroom.utility.DirectoryUtility; import com.ferid.app.classroom.utility.PermissionProcessor; import org.apache.poi.hssf.usermodel.HSSFCell; import org.apache.poi.hssf.usermodel.HSSFRow; import org.apache.poi.hssf.usermodel.HSSFSheet; import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.apache.poi.poifs.filesystem.POIFSFileSystem; import java.io.File; import java.io.FileInputStream; import java.util.ArrayList; import java.util.Iterator; /** * Created by ferid.cafer on 4/15/2015.<br /> * Adds and removes students. */ public class EditStudentActivity extends AppCompatActivity { private Context context; private RecyclerView list; private ArrayList<Student> arrayList = new ArrayList<>(); private EditStudentsAdapter adapter; private TextView emptyText; //empty list view text private Classroom classroom; private FloatingActionButton floatingActionButton; private ProgressDialog progressDialog; private static final int REQUEST_IMPORT_EXCEL = 100; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.editable_list); Bundle args = getIntent().getExtras(); if (args != null) { classroom = args.getParcelable("classroom"); } context = this; //toolbar setToolbar(); list = (RecyclerView) findViewById(R.id.list); adapter = new EditStudentsAdapter(context, arrayList); list.setAdapter(adapter); list.setLayoutManager(new LinearLayoutManager(context)); list.setHasFixedSize(true); emptyText = (TextView) findViewById(R.id.emptyText); emptyText.setText(getString(R.string.emptyMessageStudent)); floatingActionButton = (FloatingActionButton) findViewById(R.id.floatingActionButton); setFloatingButton(); addPopupClickListener(); new SelectStudents().execute(); } /** * Create toolbar and set its attributes */ private void setToolbar() { Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); setSupportActionBar(toolbar); if (getSupportActionBar() != null) { getSupportActionBar().setDisplayHomeAsUpEnabled(true); getSupportActionBar().setHomeButtonEnabled(true); } if (classroom != null) { setTitle(classroom.getName()); } } /** * Set empty list text */ private void setEmptyText() { if (emptyText != null) { if (arrayList.isEmpty()) { emptyText.setVisibility(View.VISIBLE); } else { emptyText.setVisibility(View.GONE); } } } /** * Add new student item */ private void addNewItem() { final PromptDialog promptDialog = new PromptDialog(context); promptDialog.setPositiveButton(getString(R.string.ok)); promptDialog.setOnPositiveClickListener(new PromptListener() { @Override public void OnPrompt(String promptText) { closeKeyboard(); promptDialog.dismiss(); if (!TextUtils.isEmpty(promptText)) { new InsertStudent().execute(promptText); } } }); promptDialog.show(); } /** * Change the name of the selected student * @param studentId current student to be changed * @param content current name of the student */ private void editStudent(final int studentId, final String content) { final PromptDialog promptDialog = new PromptDialog(context); promptDialog.setContent(content); promptDialog.setPositiveButton(getString(R.string.ok)); promptDialog.setOnPositiveClickListener(new PromptListener() { @Override public void OnPrompt(String promptText) { closeKeyboard(); promptDialog.dismiss(); if (!TextUtils.isEmpty(promptText)) { new UpdateStudent().execute(String.valueOf(studentId), promptText); } } }); promptDialog.show(); } /** * Delete student * @param student Student */ private void deleteStudent(final Student student) { //show alert before deleting CustomAlertDialog customAlertDialog = new CustomAlertDialog(context); customAlertDialog.setMessage(student.getName() + getString(R.string.sureToDelete)); customAlertDialog.setPositiveButtonText(getString(R.string.delete)); customAlertDialog.setNegativeButtonText(getString(R.string.cancel)); customAlertDialog.setOnClickListener(new OnAlertClick() { @Override public void OnPositive() { new DeleteStudent().execute(student.getId()); } @Override public void OnNegative() { //do nothing } }); customAlertDialog.showDialog(); } /** * Set floating action button with its animation */ private void setFloatingButton() { new Handler().post(new Runnable() { @Override public void run() { floatingActionButton.setImageResource(R.drawable.ic_action_add); floatingActionButton.show(); } }); floatingActionButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { addNewItem(); } }); } /** * Pop-up menu item click event */ public void addPopupClickListener() { adapter.setPopupClickListener(new PopupClickListener() { @Override public void OnPopupClick(int itemPosition, int menuPosition) { if (arrayList != null && arrayList.size() > itemPosition) { Student student = arrayList.get(itemPosition); if (menuPosition == StudentPopup.CHANGE_NAME.getValue()) { editStudent(student.getId(), student.getName()); } else if (menuPosition == StudentPopup.DELETE_STUDENT.getValue()) { deleteStudent(student); } } } }); } /** * Select students from DB */ private class SelectStudents extends AsyncTask<Void, Void, ArrayList<Student>> { @Override protected ArrayList<Student> doInBackground(Void... params) { ArrayList<Student> tmpList = null; if (classroom != null) { DatabaseManager databaseManager = new DatabaseManager(context); tmpList = databaseManager.selectStudents(classroom.getId()); } return tmpList; } @Override protected void onPostExecute(ArrayList<Student> tmpList) { arrayList.clear(); if (tmpList != null) { arrayList.addAll(tmpList); adapter.notifyDataSetChanged(); setEmptyText(); } } } /** * Insert student name into DB */ private class InsertStudent extends AsyncTask<String, Void, Boolean> { @Override protected Boolean doInBackground(String... params) { boolean isSuccessful = false; String student = params[0]; if (classroom != null) { DatabaseManager databaseManager = new DatabaseManager(context); isSuccessful = databaseManager.insertStudent(classroom.getId(), student); } return isSuccessful; } @Override protected void onPostExecute(Boolean isSuccessful) { if (isSuccessful) { new SelectStudents().execute(); } } } /** * Update student name in the DB */ private class UpdateStudent extends AsyncTask<String, Void, Boolean> { @Override protected Boolean doInBackground(String... params) { boolean isSuccessful = false; String studentId = params[0]; String newName = params[1]; if (classroom != null) { DatabaseManager databaseManager = new DatabaseManager(context); isSuccessful = databaseManager.updateStudentName(studentId, newName); } return isSuccessful; } @Override protected void onPostExecute(Boolean isSuccessful) { if (isSuccessful) { new SelectStudents().execute(); } } } /** * Insert multiple student names into DB */ private class InsertMultipleStudents extends AsyncTask<ArrayList<String>, Void, Boolean> { @Override protected Boolean doInBackground(ArrayList<String>... params) { boolean isSuccessful = false; ArrayList<String> studentsList = params[0]; DatabaseManager databaseManager = new DatabaseManager(context); if (classroom != null) { for (String student : studentsList) { isSuccessful = databaseManager.insertStudent(classroom.getId(), student); //if any of them fails stop going further if (!isSuccessful) break; } } return isSuccessful; } @Override protected void onPostExecute(Boolean isSuccessful) { if (progressDialog != null) { progressDialog.dismiss(); } if (isSuccessful) { new SelectStudents().execute(); } else { excelFileError(); } } } /** * Delete a student item from DB */ private class DeleteStudent extends AsyncTask<Integer, Void, Boolean> { @Override protected Boolean doInBackground(Integer... params) { int studentId = params[0]; DatabaseManager databaseManager = new DatabaseManager(context); boolean isSuccessful = databaseManager.deleteStudent(studentId, classroom.getId()); return isSuccessful; } @Override protected void onPostExecute(Boolean isSuccessful) { if (isSuccessful) { new SelectStudents().execute(); } } } /** * Check permission before going to excel sheet.<br /> * If permission is granted file browser starts to import from excel. */ private void checkPermissionForExcel() { PermissionProcessor permissionProcessor = new PermissionProcessor(this, list); permissionProcessor.setPermissionGrantListener(new PermissionGrantListener() { @Override public void OnGranted() { browseFiles(); } }); permissionProcessor.askForPermissionExternalStorage(); } @Override public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) { if (requestCode == PermissionProcessor.REQUEST_EXTERNAL_STORAGE) { // If request is cancelled, the result arrays are empty. if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { browseFiles(); } } } /** * Import students form excel * @param fileName Excel file name */ private void readXlsFile(String fileName) { ArrayList<String> studentsList = new ArrayList<>(); progressDialog = ProgressDialog.show(this, getString(R.string.wait), getString(R.string.ongoing), true, false); try { // Creating Input Stream File file = new File(fileName); FileInputStream fileInputStream = new FileInputStream(file); // Create a POIFSFileSystem object POIFSFileSystem poifsFileSystem = new POIFSFileSystem(fileInputStream); // Create a workbook using the File System HSSFWorkbook hssfWorkbook = new HSSFWorkbook(poifsFileSystem); // Get the first sheet from workbook HSSFSheet hssfSheet = hssfWorkbook.getSheetAt(0); // Iterate through the cells Iterator rowIter = hssfSheet.rowIterator(); StringBuilder studentName; //full name while (rowIter.hasNext()) { studentName = new StringBuilder(""); HSSFRow hssfRow = (HSSFRow) rowIter.next(); Iterator cellIter = hssfRow.cellIterator(); while (cellIter.hasNext()) { HSSFCell currentCell = (HSSFCell) cellIter.next(); if (!currentCell.toString().trim().equals("")) { //put space in between name, surname, etc. if (studentName.toString().length() > 0) { studentName.append(" "); } studentName.append(currentCell.toString()); } } //add to list if (!studentName.toString().equals("")) { studentsList.add(studentName.toString()); } } } catch (Exception e) { progressDialog.dismiss(); excelFileError(); } if (!studentsList.isEmpty()) { new InsertMultipleStudents().execute(studentsList); } else { progressDialog.dismiss(); } } /** * Get the path of the excel file to import students list */ private void browseFiles() { //if directory is not mounted do not start the operation if (DirectoryUtility.isExternalStorageMounted()) { Intent intent = new Intent(Intent.ACTION_GET_CONTENT); intent.setType("*/*"); intent.addCategory(Intent.CATEGORY_OPENABLE); try { startActivityForResult(Intent.createChooser(intent, getString(R.string.selectFile)), REQUEST_IMPORT_EXCEL); } catch (ActivityNotFoundException e) { excelFileError(); } } else { Snackbar.make(list, getString(R.string.mountExternalStorage), Snackbar.LENGTH_LONG).show(); } } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); if (requestCode == REQUEST_IMPORT_EXCEL) { if (resultCode == RESULT_OK) { String filePath = data.getData().getPath(); //only xls and xlsx extensions are allowed if (!filePath.endsWith("xls")) { Snackbar.make(list, getString(R.string.extensionWarningXls), Snackbar.LENGTH_LONG).show(); return; } if (filePath.contains(":")) { String[] partFilePath = filePath.split(":"); if (partFilePath.length == 2) { readXlsFile(Environment.getExternalStorageDirectory() + "/" + partFilePath[1]); } else { excelFileError(); } } else { readXlsFile(filePath); } } } } /** * Excel related error */ private void excelFileError() { Snackbar.make(list, getString(R.string.excelError), Snackbar.LENGTH_LONG).show(); } /** * Closes keyboard for disabling interruption */ private void closeKeyboard() { try { InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE); imm.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS); } catch (Exception ignored) { } } private void closeWindow() { finish(); overridePendingTransition(R.anim.stand_still, R.anim.move_out_to_bottom); } @Override public void onBackPressed() { closeWindow(); } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.menu_upload, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle action bar actions click switch (item.getItemId()) { case android.R.id.home: closeWindow(); return true; case R.id.upload: checkPermissionForExcel(); return true; default: return super.onOptionsItemSelected(item); } } }