Public void insertPressed(View view) {
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- // 4. Use the DAO functions to insert the Employee into the database // 5. Show a success message
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Insert Using the GUI public void insertPressed(View view) { // 1. Get the values from the form fields (in the UI) // 2. Validate that the user has provided all the necessary information // 3. Create a new Employee object using the form data // 4. Use the DAO functions to insert the Employee into the database // 5. Show a success message // 6. Clear all the form fields and prepare to receive new data } Step 1 & 2: Getting the values from the form fields and validating // 1. Get the values from the form fields (in the UI) EditText etName = findViewById(R.id.etName); EditText etDateHired = findViewById(R.id.etDateHired); // 2. Validate that the user has provided all the necessary information if (etName.getText().toString().isEmpty() || etDateHired.toString().isEmpty() ) { Log.d("ABC", "Sorry, you must enter all fields."); // exit the function return; } Step 3: Using the form data to create a new Employe object and insert Employee e1 = new Employee(etName.getText().toString(), etDateHired.getText().toString()); empDAO.insert(e1); Log.d("ABC", e1.name + " was inserted."); Expected Result: Get all employees public void getAllPressed(View view) { // get all employees List // output the employees to the console for (int i = 0; i < employeeList.size(); i++) { Log.d("ABC", employeeList.get(i).toString()); } // @TODO: Output all the employees to a ListView } Get The total number of employees 1/ Add a DAO function to query the database for the number of employees @Dao public interface EmployeeDAO { // Create a function that returns the total number of employees in the database // SQL --> to get the total number of employees in the employee table? // name = employees // Let me know in teh chat box @Query("SELECT COUNT(*) FROM employees") public int getNumEmployees(); } 2/ Update your Button to use your new function public void getTotalCountPressed(View view) { // List // Log.d("ABC", "The number of employees is: " + employeeList.size()); int count = empDAO.getNumEmployees(); Log.d("ABC", "The number of employees is: " + count); } Exercise: Write a DAO function that returns the employees names (names only, no other info) @Query("SELECT name FROM employees") public List // Creat a function that returns the FIRST employee in the database // (but only their name) // What modification do i need to make to only return ONE employee name @Query("SELECT name FROM employees LIMIT 1") public String getOneName(); Performing a WHERE operation DAO: @Query("SELECT * FROM employees WHERE name = :empName") public List MainActivty: List Log.d("ABC", employeesNamedPeter.toString()); Performing a where with multiple cluases @Query("SELECT * FROM employees WHERE name = :empName") public List // Example: Create a dao function that gets the hiring date of an employee with a specified id @Query("SELECT date_hired FROM employees WHERE id = :empId") public String getEmployeeHireDate(int empId); @Query("SELECT * FROM employees WHERE name = :empName AND date_hired=:hireDate") public Employee getEmployeeByNameAndHireDate(String empName, String hireDate); ------------ Example of how to use the dao functions in your MainActivity List Log.d("ABC", employeesNamedPeter.toString()); String hireDate = empDAO.getEmployeeHireDate(11); Log.d("ABC", "Frank was hired on: " + hireDate); Delete Download 103.36 Kb. Share with your friends:
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