Mobiapp

• User Interface

  The "face" of a program or application, everything that a program user can see and/or interact with
• User Interface Element Builder Objects

  • View Object - draws something on the screen that the user can interact with
  • ViewGroup Object - holds other View and/or ViewGroup objects for defining the layout of the interface
• Common User Interface Components

  • App Bar (or Action Bar) - provides visual structure and interactive elements familiar to users
  • Dialog - a small window that prompts the user to make a decision or enter additional information
  • Notifications - messages displayed outside of the application's normal interface
  • Toasts - small pop-ups that provide simple feedback about an operation
• Layout

  The "framework" of an interface that arranges its contents in a pleasing or orderly manner, defines the visual structure for a user interface
• Two ways to declare layouts in Android projects

  • Declared UI elements in XML
  • Instantiation of Elements at Runtime
• Common Types of App Layouts

  • Linear Layout - aligns all children in a single direction
  • Relative Layout - displays child views in relative positions
  • List View - displays items in a vertically scrolling list
  • Grid View - displays items in a two-dimensional scrollable grid
• Input Controls

  • Buttons
  • Text Fields
  • Checkboxes
  • Radio Buttons
  • Toggle Buttons
  • Spinners
  • Pickers
• Buttons

  Can be created using Button class, ImageButton class, or Button class with android:drawableLeft attribute
• Text Fields

  Enable a user to enter text, can be single-line or multi-line
• Checkboxes

  Allow users to choose one or more options from a set number of choices
• Radio Buttons

  Allow the user to select only one option from a set of choices
• Toggle Buttons

  Allow users to change a setting between two states
• Spinners

  Provide a quick way to choose a value from a choice set
• Pickers

  Used for time and date selection via a dialog