如何拨打未接来电？

Question

我正在开发一个我想要的 Android 应用程序 能够拨打电话，但有非常精确的限制，这是 “拨打未接来电”。我想要的是，能够挂断电话 电话铃声响起的那一刻。

现在我能够知道手机何时开始尝试并拨打电话 呼叫，但几秒钟内没有“响铃”活动 网络，这是我愿意做的。

我怎样才能停止这一刻呢？

Answer 1

通过 PhoneStateListener 使用 onCallStateChanged() 只能检测手机何时开始拨出电话以及何时挂断拨出电话，但无法确定何时开始“响铃”。我尝试过一次，查看下面的代码：

拨出时从IDLE开始到OFFHOOK，挂机时到IDLE。
唯一的解决方法是使用计时器在拨出电话开始并经过几秒钟后挂断电话，但是，您永远无法保证电话会开始响铃。

代码如下：

  public abstract class PhoneCallReceiver extends BroadcastReceiver {
        static CallStartEndDetector listener;

  

    @Override
    public void onReceive(Context context, Intent intent) {
        savedContext = context;
        if(listener == null){
            listener = new CallStartEndDetector();
        }


            TelephonyManager telephony = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE); 
        telephony.listen(listener, PhoneStateListener.LISTEN_CALL_STATE);
    }

   

    public class CallStartEndDetector extends PhoneStateListener {
        int lastState = TelephonyManager.CALL_STATE_IDLE;
        boolean isIncoming;

        public PhonecallStartEndDetector() {}


        //Incoming call-   IDLE to RINGING when it rings, to OFFHOOK when it's answered, to IDLE when hung up
        //Outgoing call-  from IDLE to OFFHOOK when dialed out, to IDLE when hunged up

        @Override
        public void onCallStateChanged(int state, String incomingNumber) {
            super.onCallStateChanged(state, incomingNumber);
            if(lastState == state){
                //No change
                return;
            }
            switch (state) {
                case TelephonyManager.CALL_STATE_RINGING:
                    isIncoming = true;
                     //incoming call started
                    break;
                case TelephonyManager.CALL_STATE_OFFHOOK:
                    //Transition of ringing->offhook are pickups of incoming calls.  Nothing down on them
                    if(lastState != TelephonyManager.CALL_STATE_RINGING){
                        isIncoming = false;
                       //outgoing call started
                    }
                    break;
                case TelephonyManager.CALL_STATE_IDLE:
                    //End of call(Idle).  The type depends on the previous state(s)
                    if(lastState == TelephonyManager.CALL_STATE_RINGING){
                        // missed call
                    }
                    else if(isIncoming){
                          //incoming call ended
                    }
                    else{
                       //outgoing call ended                                              
                    }
                    break;
            }
            lastState = state;
        }

    }



}

Answer 2

在 PhoneStateListener 中使用 onCallStateChanged()