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>