Broadcast Intents are used to notify applications of system or application events, extending the event-driven programming model between applications Broadcasting Intents helps make your application more open; by broadcasting an event using an Intent, you let yourself and third-party developers react to events without having to modify your original application. Within your applications you can … Read more
To linkify your own data, you need to define your own linkify strings. Do this by creating a new RegEx pattern that matches the text you want to display as hyperlinks. As with the native types, you can linkify the target Text View by calling Linkify.addLinks; however, rather than passing in one of the preset … Read more
Linkify is a helper class that creates hyperlinks within Text View (and Text View-derived) classes through RegEx pattern matching Text that matches a specified RegEx pattern will be converted into a clickable hyperlink that implicitly fi res startActivity(new Intent(Intent.ACTION_VIEW, uri)), using the matched text as the target URI. Native Linkify Link Types The Linkify class … Read more
Native Android applications also use Intents to launch Activities and sub-Activities. The following (noncomprehensive) list shows some of the native actions available as static string constants in the Intent class. When creating implicit Intents, you can use these actions, known as Activity Intents, to start Activities and sub-Activities within your own applications ACTION_ALL_APPS — Opens … Read more
An implicit Intent is a mechanism that lets anonymous application components service action requests. That means you can ask the system to start an Activity to perform an action without knowing which application, or Activity, will be started. For example, to let users make calls from your application, you could implement a new dialer, or … Read more
Intents are used as a message-passing mechanism that works both within your application and between applications. You can use Intents to do the following: Explicitly start a particular Service or Activity using its class name Start an Activity or Service to perform an action with (or on) a particular piece of data Broadcast that an … Read more
In most cases you won’t have to create your own Adapters from scratch. Android supplies a set of Adapters that can pump data from common data sources (including arrays and Cursors) into the native controls that extend Adapter View Because Adapters are responsible both for supplying the data and for creating the Views that represent … Read more
For your new View to be interactive, it will need to respond to user-initiated events such as key presses, screen touches, and button clicks. Android exposes several virtual event handlers that you can use to react to user input: onKeyDown — Called when any device key is pressed; includes the D-pad, keyboard, hang-up, call, back, … Read more
Android supplies a toolbox of standard Views to help you create your UIs. By using these controls (and modifying or extending them, as necessary), you can simplify your development and provide consistency between applications The following list highlights some of the more familiar toolbox controls: TextView — A standard read-only text label that supports multiline … Read more
The Android SDK includes a number of Fragment subclasses that encapsulate some of the most common Fragment implementations. Some of the more useful ones are listed here: DialogFragment — A Fragment that you can use to display a floating Dialog over the parent Activity. You can customize the Dialog’s UI and control its visibility directly … Read more