Android4.0 new connector feature WI-FI direct

WiFi direct technology Overview

Wi-Fi direct allows devices in a wireless network to connect to each other without using a wireless router. Similar to Bluetooth technology, this standard allows wireless devices to interconnect in point-to-point mode, but it significantly improves transmission speed and distance compared with Bluetooth.

Features of Wi-Fi direct technology

Mobility and Portability: Wi-Fi direct devices can connect to each other anytime, anywhere. Because you do not need a Wi-Fi router or access point, a Wi-Fi device can be connected anywhere.

Instant availability: users will be able to establish direct connections using the first Wi-Fi Direct Authentication device that takes home. For example, a newly purchased Wi-Fi direct notebook can be directly connected to a user's existing traditional Wi-Fi device.

Ease of use: the Wi-Fi direct device discovery and service discovery functions help users determine available devices and services and establish connections. For example, if users want to print files, they can use the above service to find out which Wi-Fi network has a printer.

Simple and secure connection: Wi-Fi direct devices use Wi-Fi Protected setup to simplify the process of creating secure connections between devices. You can press the button on any device or enter a PIN code (that is, the PIN code displayed on the device) to easily create a secure connection.

 

Wi-Fi direct has the following advantages: high transmission rate and compatibility with original devices.

Major disadvantage of Wi-Fi direct: High Power Consumption (compared with Bluetooth ).

 

Android P2P source code learning

①: Wifip2pset1_wi-fi P2P settings

 

Method	Explanation
Mreceiver	Process various received action methods: Wifi_p2p_peers_changed_action: Call requestpeers; Wifi_p2p_connection_changed_action: Obtain networkinfo and determine whether it is in the connection status; Wifi_p2p_this_device_changed_action: Call updatedevicepref
Oncreate	Called at creation Obtain the system service wifip2pmanager and wifip2pmanager. Channel; mconnectlistener/mdisconnectlistener set listener for wifip2pdialog; sethasoptionsmenu (true) set operation menu
Onresume ()	Register mcycler; discoverpeers () to explore nearby devices
Onpause ()	Log out of mcycler;
Onoptionsitemselected	Menu Event Response: Menu_id_search: discoverpeers () to explore nearby devices; Menu_id_create_group: creategroup () creates a group; Menu_id_remove_group: removegroup () removes a group; Menu_id_advanced: not processed;
Onpreferencetreeclick	Click a device. The related dialog box is displayed.
Updatedevicepref	Update Device Properties First, set the device configuration information, and then call Onpeersavailable () method to update the UI
Onpeersavailable	Update the UI

 

 

②

Wifip2pdialog Method	Explanation
Getconfig ()	Obtain P2P configuration information and device address and WPS
Oncreate	Call at creation and set the address and name of the device.

 

 

 

③

Wifip2penabler

Method	Understanding
Mreceiver	Process various received action methods: Wifi_p2p_state_changed_action: Call Method Handlep2pstatechanged () for processing
Handlep2pstatechanged	Set the checkbox attribute value based on the status.
Onpreferencechange	Enable/disable WiFi P2P Based on the checkbox attribute changes
Resume/pause	Register/deregister mcycler, set/cancel the listener of checkbox

 

 

 

④

 

Wifip2ppeer

Method	Understanding
Onbindview	Set the basic configuration information (the name, address, the image of the received image and the semaphore ), Set summary with refresh ()
Compareto	Checks whether a device is the same as a local device.
Getlevel	Obtain signal level