Lecture 14: UI Controls in Android скачать в хорошем качестве

Lecture 14: UI Controls in Android

UI Controls in Android: In android UI or input controls are the interactive or View components that are used to design the user interface of an application. In android we have a wide variety of UI or input controls available, those are TextView, EditText, Buttons, Checkbox, Progressbar, Spinners, etc. Generally, in android the user interface of an app is made with a collection of View and ViewGroup objects. The View is a base class for all UI components in android and it is used to create interactive UI components such as TextView, EditText, Checkbox, Radio Button, etc. and it is responsible for event handling. The ViewGroup is a subclass of View and it will act as a base class for layouts. The ViewGroup will provide invisible containers to hold other Views or ViewGroups and to define the layout properties. In android, we can define a UI or input controls in two ways, those are: 1. Declare UI elements in XML 2. Create UI elements at runtime 2. Create UI Element at Runtime: TextView t = new TextView(this); t.setText("Enter your Name:"); EditText e = new EditText(this); e.setText("Enter Name"); LinearLayout l = new LinearLayout(this); l.addView(t); l.addView(e); setContentView(linearLayout); Following are the commonly used UI or input controls in android applications. 1. TextView 2. EditText 3. AutoCompleteTextView 4. Button 5. ImageButton 6. ToggleButton 7. CheckBox 8. RadioButton 9. RadioGroup 10. ProgressBar 11. Spinner 12. TimePicker 13. DatePicker 14. SeekBar 15. AlertDialog 16. Switch 17. RatingBar