[转] How to detect incoming calls in an Android

原文地址：https://stackoverflow.com/a/15564021

实测可用。
测试手机：
MeiZu MX4 Android 5.1
HuaWei Mate 8 Android 7.0

-----------------------------------------------------------
Here's what I use to do this:

AndroidManifest:

<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.PROCESS_OUTGOING_CALLS"/>

<!--This part is inside the application-->
<receiver android:name=".CallReceiver" >
    <intent-filter>
        <action android:name="android.intent.action.PHONE_STATE" />
    </intent-filter>
    <intent-filter>
        <action android:name="android.intent.action.NEW_OUTGOING_CALL" />
    </intent-filter>
</receiver>

My base reusable call detector

package com.gabesechan.android.reusable.receivers;
import java.util.Date;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.telephony.TelephonyManager;

public abstract class PhonecallReceiver extends BroadcastReceiver {

    //The receiver will be recreated whenever android feels like it.  We need a static variable to remember data between instantiations

    private static int lastState = TelephonyManager.CALL_STATE_IDLE;
    private static Date callStartTime;
    private static boolean isIncoming;
    private static String savedNumber;  //because the passed incoming is only valid in ringing


    @Override
    public void onReceive(Context context, Intent intent) {

        //We listen to two intents.  The new outgoing call only tells us of an outgoing call.  We use it to get the number.
        if (intent.getAction().equals("android.intent.action.NEW_OUTGOING_CALL")) {
            savedNumber = intent.getExtras().getString("android.intent.extra.PHONE_NUMBER");
        }
        else{
            String stateStr = intent.getExtras().getString(TelephonyManager.EXTRA_STATE);
            String number = intent.getExtras().getString(TelephonyManager.EXTRA_INCOMING_NUMBER);
            int state = 0;
            if(stateStr.equals(TelephonyManager.EXTRA_STATE_IDLE)){
                state = TelephonyManager.CALL_STATE_IDLE;
            }
            else if(stateStr.equals(TelephonyManager.EXTRA_STATE_OFFHOOK)){
                state = TelephonyManager.CALL_STATE_OFFHOOK;
            }
            else if(stateStr.equals(TelephonyManager.EXTRA_STATE_RINGING)){
                state = TelephonyManager.CALL_STATE_RINGING;
            }


            onCallStateChanged(context, state, number);
        }
    }

    //Derived classes should override these to respond to specific events of interest
    protected abstract void onIncomingCallReceived(Context ctx, String number, Date start);
    protected abstract void onIncomingCallAnswered(Context ctx, String number, Date start);
    protected abstract void onIncomingCallEnded(Context ctx, String number, Date start, Date end);

    protected abstract void onOutgoingCallStarted(Context ctx, String number, Date start);      
    protected abstract void onOutgoingCallEnded(Context ctx, String number, Date start, Date end);

    protected abstract void onMissedCall(Context ctx, String number, Date start);

    //Deals with actual events

    //Incoming call-  goes from IDLE to RINGING when it rings, to OFFHOOK when it's answered, to IDLE when its hung up
    //Outgoing call-  goes from IDLE to OFFHOOK when it dials out, to IDLE when hung up
    public void onCallStateChanged(Context context, int state, String number) {
        if(lastState == state){
            //No change, debounce extras
            return;
        }
        switch (state) {
            case TelephonyManager.CALL_STATE_RINGING:
                isIncoming = true;
                callStartTime = new Date();
                savedNumber = number;
                onIncomingCallReceived(context, number, callStartTime);
                break;
            case TelephonyManager.CALL_STATE_OFFHOOK:
                //Transition of ringing->offhook are pickups of incoming calls.  Nothing done on them
                if(lastState != TelephonyManager.CALL_STATE_RINGING){
                    isIncoming = false;
                    callStartTime = new Date();
                    onOutgoingCallStarted(context, savedNumber, callStartTime);                     
                }
                else
                {
                    isIncoming = true;
                    callStartTime = new Date();
                    onIncomingCallAnswered(context, savedNumber, callStartTime); 
                }

                break;
            case TelephonyManager.CALL_STATE_IDLE:
                //Went to idle-  this is the end of a call.  What type depends on previous state(s)
                if(lastState == TelephonyManager.CALL_STATE_RINGING){
                    //Ring but no pickup-  a miss
                    onMissedCall(context, savedNumber, callStartTime);
                }
                else if(isIncoming){
                    onIncomingCallEnded(context, savedNumber, callStartTime, new Date());                       
                }
                else{
                    onOutgoingCallEnded(context, savedNumber, callStartTime, new Date());                                               
                }
                break;
        }
        lastState = state;
    }
}

Then to use it, simply derive a class from it and implement a few easy functions, whichever call types you care about:

public class CallReceiver extends PhonecallReceiver {

    @Override
    protected void onIncomingCallReceived(Context ctx, String number, Date start)
    {
        //
    }

    @Override
    protected void onIncomingCallAnswered(Context ctx, String number, Date start)
    {
        //
    }

    @Override
    protected void onIncomingCallEnded(Context ctx, String number, Date start, Date end)
    {
        //
    }

    @Override
    protected void onOutgoingCallStarted(Context ctx, String number, Date start)
    {
        //
    } 

    @Override 
    protected void onOutgoingCallEnded(Context ctx, String number, Date start, Date end)
    {
        //
    }

    @Override
    protected void onMissedCall(Context ctx, String number, Date start)
    {
        //
    }

}

In addition you can see a writeup I did on why the code is like it is on my blog. Gist link: https://gist.github.com/ftvs/e61ccb039f511eb288ee

EDIT: Updated to simpler code, as I've reworked the class for my own use