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Android - Basic Steps (UI)

View Elements

  • Button
  • ToggleButton
  • Checkbox
  • RatingBar
  • AutoCompleteTextView

ViewGroups

  • RadioGroup
  • TimePicker
  • DatePicker
  • WebView
  • MapView
  • Gallery
  • Spinner

Adapters & AdapterViews

  • AdapterView are Views managed by an Adapter, who manage the data and provides data views
  • AdapterView display the View
    • ListView manage by ListAdapter
    • Spinner manage by SpinnerAdapter

Layouts

match_parent - Occupy all the available space. Deprecated starting in API Level 8 
fill_parent - Same asd match_parent but for API Level 8
  • LinearLayout
    • Arrange all the child elements in one line
  • RelativeLayout
  • TableLayout
  • GridView

Menus

  • Is defined in a resource XMLfile   res/menu/file.xml
  • Use it on method OnCreate...Menu(), using the menu inflater
  • Use method on...ItemSelection() to handle the item selection

Types

  • Options
    • When user press a button
    • In the method onCreateOptionsMenu() add the code to add the menu defined in res/menu/file.xml
                 getMenuInflater().inflate(R.menu.menu, menu);
  • Context
    • When  user touches and holds a view
  • Submenu
    • When user touches a visible menu item
  • ActionBar
    • This line show the menu as ActionBar, showing the text only is space available
      • android:showAsAction="ifRoom|withText"
  • ActionBar (Tab)

Dialog

  • Show a pop-up with the options like Yes/No


TIPS

  • To add predifined icons use
    • android:icon="@android:drawable/ic_menu_directions"
  • To include in the Layout another element use the tag <include>
      • Where @layout/first is the second layout file named first.xml
    <include
        android:id="@+id/include2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        layout="@layout/first" >
    </include>

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