Question

Create an android app. Use a singleton for the contacts.

App creates and manages a list of contacts. The contacts in a file which is loaded by the app upon starting. The first time the app it runs there ONE dummy contact.
A contact contains: First Name, Last Name, Company, a phone and an of email.
1) The app uses the Recycle View and the Pager and displays the list of contacts.When you are a contact you can swipe to get the enxt or the previous contact.
2) Upon clicking on a contact, (not clicking a button, (i.e. make the LinearLayout clickable, add an instance var, inflate the layout, and add a listener to the layout, as you would add a listener to a button), the Pager View starts, and displays the clicked contact, ready to be edited, PLUS four buttons "Add new contact", "Remove this contact". OK and CANCEL
2.1) Upon clicking the "Remove this contact" an alert-dilaog appears that asks ---"Delete this contact?", yes, no ---and the contact is removed if the user presses yes, and then we return to the Recycle View automatically. If the contact is removed a Toast appears that the contact was successfully removed.
2.2) Upon clicking the "Add new contact" a new Dialog( i.e. as with DatePicker appears. The Dialog contains needed fields to enter a new contact. In addition to the fields to enter the contact-info, the Dialog has an OK and a CANCEL button. OK displays a Toast of success and sends the new contact to the parent of this Fragment, to the Recycle View and finally is saved into the list of the Model, and retuens the user to the Recycle View. The CANCEL cancels any sending of info and returns the user to the Recycle View.
2.3) The OK button terminates the fragment of the Pager View. and sends all changes to its parent and via the parent to the Recycle View. We return to the parent after clicking.
2.4) The CANCEL button terminates the fragment of the Pager View, and sends NO changes to the its parent. We return to the parent after clicking.
3)Upon terminating the app the existing list is saved into the file.

Answer 1

The question pertains to creating an Android app that manages a list of contacts using a singleton pattern. The app includes features such as a Recycle View, Pager View, and various actions for editing, removing, and adding contacts.

Step-by-step explanation:

The subject of this question is Computers and Technology. The question pertains to creating an Android app that manages a list of contacts. The app uses a singleton design pattern to ensure that there is only one instance of the contacts list throughout the app.

The app loads the contacts from a file upon starting. Upon clicking on a contact, a Pager View is displayed with the clicked contact ready for editing. This view also contains buttons for adding a new contact, removing the current contact, and saving or canceling any changes made.

When the app is terminated, the existing list of contacts is saved back into the file.