手机通话的状态

1. 最多可以有多少路通话：

最多有三通独立电话存在（ForegroundCall、BackgroundCall、RingingCall）,最多有7路connections（conference call），这只是软件所能支持的最大个数，具体支持能力需要看运营商的网络。

 

2. call 的状态：

Idle, Active, Dailing, Alerting 【ForegroundCall】

Idle, Holding 【BackgroundCall】

Idle Incoming Waiting【RingingCall】

Disconnecting, Disconnected.【三种call都有】

 

call 的类型：

ForegroundCall、BackgroundCall、RingingCall

 

3. phone 的状态：

IDLE,  RINGING,  OFFHOOK

如果有一通Activitecall 和一通 waitingcall，当前 phone 为RINGING.

 

源码phone状态注释说明

    /**

     * The phone state. One of the following:<p>

     * <ul>

     * <li>IDLE = nophone activity</li>

     * <li>RINGING = aphone call is ringing or call waiting.

     * In the latter case, another call is active as well</li>

     * <li>OFFHOOK = Thephone is off hook. At least one call

     * exists that is dialing, active orholding and no calls are

     * ringing or waiting.</li>

     * </ul>

     */