Mobiiliarvutus ja asjade internet 2021/22 sügis

Homework 1: Plant Care App

Let's start building an app for browsing & tracking plants (in a greenhouse, in an apartment etc). In this homework, we will focus on a single sub-part of the app - the detailed view of a single plant. Here, the user can see the plant's essential information and write entries about how the plant has been taken care of. This homework has 2 parts:

1. Implementing an Android app
2. Conducting experiments with the app and answering questions

You can choose any plant for your solution to fill the content!

Part 1: Plant Care App

• Create a new project and design a graphical interface with some interactive behavior according to the below requirements.
  • use minSDK API v21
  • Locate your project in a sub-folder within your GitLab repo called homework1

The UI has 2 sections: Plant Information and Plant Care Log

Plant Information Section

• An ImageView and TextView should be used to show a picture of the plant and it's name
  • ImageView should show a drawable image resource
  • Plant name TextView should have a fontsize larger than the default
• A "Tips" Button next to the Plant name should open a pop-up Dialog showing additional background information about it, e.g. how to care for it.
  • See Tips below for a hint how to do this

Plant Care Log Section

The user can enter their plant-care activities into an activity log:

• An EditText should allow user to enter text
• A LinearLayout will show the text entries the user has entered
  • Make the LinearLayout scrollable by placing it inside a ScrollView!
• A "Save" Button is used to take the user input and add it to the LinearLayout
  • Hitting Save should add a new TextView to the children of the LinearLayout
• A Checkbox allows the user enable automatic date prefixes to their plant log entries
  • If enabled, a formatted date (DD/MM/YYYY) is prepended to whatever the user's input was when they hit "Save"
• A TextView displays the no. of entries currently in the activity log.
• All of the described Widgets should be laid out using a ConstraintLayout.
• The Plant Information section should vertically appear above the Plant Care Log part of the UI.
• Use Margins to create some space between the widgets, elements for a neater look.

Landscape Mode

The Application should define a 2nd resource file of the Activity, for landscape mode.

• In the landscape version, the Plant Information and Care Log should appear side-by-side (see sample screenshot)
  • Use a vertical Guideline, with a value of 50% to split the layout into two exactly at the middle.
  • Set some constraints to the Guideline to achieve the side-by-side placement

'' When you run your application and rotate the device, the App should switch between the 2 activity layout files!''

Non-Functional Requirements

• Don't use hardcoded Strings in your XML, instead use String Resources, including String resources with variables ( see tips below). Same goes for UI content in Kotlin (e.g. the plant care tips pop-up text).
• Update the colors of your application in styles.xml to something non-default.
• Please note we are not requesting for the data to be saved permanently (i.e. if the log entries are lost after closing the app, this is OK!)

Tips

• setText() and getText() methods of EditText and TextView are helpful
• You can add child Views to a LinearLayout programmatically with the .addView( .. ) method
• To show the Plant Care Tips Pop-up Dialog, you can programmatically display an AlertDialog using AlertDialog.Builder, see here for an example
• String resources with variables:
  • If you have a string resource such as <string name="greeting">Hello, %1s!</string> , where %1s represents a placeholder for a variable, you can use it in kotlin with: getString(R.strings.greeting, "John") , this will pass the 2nd argument to the placeholder of the sting resource.
• Optional: You may try using Elevation to adjust how Androids Material Design shows shadows for different UI elements

Part 2 - Observing lifecycle methods

Override the onPause(), onResume(), onStop(), onDestroy() methods as discussed in lecture 2. Write some log statements in them and answer these questions:

• Which of the methods are called & in which order when:
  • Changing device orientation
  • Hitting the home button and returning to the application
  • Hitting the back button and re-opening the application
• What happens to the EditText and TextView elements in each of these 3 cases (assuming the user has previously already entered some text into the log, plus something new has been written into the EditText and "Save" has not yet been clicked. )

Write your answers into the Readme.MD of subfolder for this homework on your GitLab.

Submission

Create a sub-folder particularly for this homework (call it homework1), it should contain the source code of your Android Studio project.

• Create a new Git TAG named homework1 for the last commit related to this homework. You can do it with the command-line git utility or from the GitLab web interface.
• Also, please update the .MD file at the root of your repository, so it contains a link to the subfolder of this homework.
• Note: Android Studio projects include a .gitignore by default, this should already take care the it, but just in case we are mentioning it - make sure you don't commit cached files or binaries, just the source code. This can happen if for some reason you have deleted the .gitignore.