前言

Android 可以監聽到你的電話的撥打狀態，從而做出相應的操作。可以監聽到三個狀態：無操作CALL_STATE_IDLE、通話中CALL_STATE_OFFHOOK、響鈴中CALL_STATE_RINGING，如果要監聽接通或結束通話的動作，需要額外的判斷。

建立你的BroadcastReceiver來接收撥打狀態

• 當手機做出撥打操作時，會發出系統廣播，我們使用BroadcastReceiver來接收；

public class PhoneStateReceive extends BroadcastReceiver {

    private Context mContext;

    @Override
 

    public void onReceive(Context context, Intent intent) {
        mContext = context;
        if (intent.getAction().equals("android.intent.action.PHONE_STATE")) {

        }
    }
}

• 建立私有屬性mCurrentState，mOldState來分別表示 當前狀態、過去狀態；

    private int mCurrentState = TelephonyManager.CALL_STATE_IDLE ;
    private
 
 int mOldState = TelephonyManager.CALL_STATE_IDLE ;

• 建立內部類：電話狀態監聽類，繼承自PhoneStateListener，用來處理電話撥打狀態；

    private class MyPhoneStateListener extends PhoneStateListener {
        @Override
        public void onCallStateChanged(int state, String incomingNumber) {
            super.onCallStateChanged(state, incomingNumber);
        }
    }
 

• 獲取mCurrentState和mOldState；mOldState由事先儲存在PreferenceHelper中的值獲取；

    private class MyPhoneStateListener extends PhoneStateListener {
        @Override
        public void onCallStateChanged(int state, String incomingNumber) {
            super.onCallStateChanged(state, incomingNumber);
            mOldState = PreferenceHelper.getInt(Config.FLAG_CALL_STATE, mContext);

            switch (state) {
                case TelephonyManager.CALL_STATE_IDLE:
                    mCurrentState = TelephonyManager.CALL_STATE_IDLE;
                    break;
                case TelephonyManager.CALL_STATE_OFFHOOK:
                    mCurrentState = TelephonyManager.CALL_STATE_OFFHOOK;
                    break;
                case TelephonyManager.CALL_STATE_RINGING:
                    mCurrentState = TelephonyManager.CALL_STATE_RINGING;
                    break;
            }
        }
    }

• 使用mCurrentState和mOldState，來判斷是否是接通還是結束通話動作；將mCurrentState儲存在SharedPreferences 中，以便下次當做過去狀態取出；

    private class MyPhoneStateListener extends PhoneStateListener {
        @Override
        public void onCallStateChanged(int state, String incomingNumber) {
            super.onCallStateChanged(state, incomingNumber);

            mOldState = PreferenceHelper.getInt(Config.FLAG_CALL_STATE, mContext);

            switch (state) {
                case TelephonyManager.CALL_STATE_IDLE:
                    mCurrentState = TelephonyManager.CALL_STATE_IDLE;
                    break;
                case TelephonyManager.CALL_STATE_OFFHOOK:
                    mCurrentState = TelephonyManager.CALL_STATE_OFFHOOK;
                    break;
                case TelephonyManager.CALL_STATE_RINGING:
                    mCurrentState = TelephonyManager.CALL_STATE_RINGING;
                    break;
            }

            if(mOldState == TelephonyManager.CALL_STATE_IDLE && mCurrentState == TelephonyManager.CALL_STATE_OFFHOOK ) {
                Log.i(Config.TAG, "onCallStateChanged: 接通");
                PreferenceHelper.putInt(Config.FLAG_CALL_STATE, mCurrentState, mContext);
            } else if (mOldState == TelephonyManager.CALL_STATE_OFFHOOK && mCurrentState == TelephonyManager.CALL_STATE_IDLE) {
                Log.i(Config.TAG, "onCallStateChanged: 結束通話");
                PreferenceHelper.putInt(Config.FLAG_CALL_STATE, mCurrentState, mContext);
            }
        }
    }

• 將你的MyPhoneStateListener 註冊到TelephonyManager中；

    @Override
    public void onReceive(Context context, Intent intent) {
        mContext = context;
        if (intent.getAction().equals("android.intent.action.PHONE_STATE")) {
            TelephonyManager tm = (TelephonyManager) context.getSystemService(Service.TELEPHONY_SERVICE);
            tm.listen(new MyPhoneStateListener(), PhoneStateListener.LISTEN_CALL_STATE);
        }
    }

• 現在PhoneStateReceive看起來是這樣的；

public class PhoneStateReceive extends BroadcastReceiver {

    private int mCurrentState = TelephonyManager.CALL_STATE_IDLE ;
    private int mOldState = TelephonyManager.CALL_STATE_IDLE ;

    private Context mContext;

    @Override
    public void onReceive(Context context, Intent intent) {
        mContext = context;
        if (intent.getAction().equals("android.intent.action.PHONE_STATE")) {
            TelephonyManager tm = (TelephonyManager) context.getSystemService(Service.TELEPHONY_SERVICE);
            tm.listen(new MyPhoneStateListener(), PhoneStateListener.LISTEN_CALL_STATE);
        }
    }

    private class MyPhoneStateListener extends PhoneStateListener {
        @Override
        public void onCallStateChanged(int state, String incomingNumber) {
            super.onCallStateChanged(state, incomingNumber);

            mOldState = PreferenceHelper.getInt(Config.FLAG_CALL_STATE, mContext);

            switch (state) {
                case TelephonyManager.CALL_STATE_IDLE:
                    mCurrentState = TelephonyManager.CALL_STATE_IDLE;
                    break;
                case TelephonyManager.CALL_STATE_OFFHOOK:
                    mCurrentState = TelephonyManager.CALL_STATE_OFFHOOK;
                    break;
                case TelephonyManager.CALL_STATE_RINGING:
                    mCurrentState = TelephonyManager.CALL_STATE_RINGING;
                    break;
            }

            if(mOldState == TelephonyManager.CALL_STATE_IDLE && mCurrentState == TelephonyManager.CALL_STATE_OFFHOOK ) {
                Log.i(Config.TAG, "onCallStateChanged: 接通");
                PreferenceHelper.putInt(Config.FLAG_CALL_STATE, mCurrentState, mContext);
            } else if (mOldState == TelephonyManager.CALL_STATE_OFFHOOK && mCurrentState == TelephonyManager.CALL_STATE_IDLE) {
                Log.i(Config.TAG, "onCallStateChanged: 結束通話");
                PreferenceHelper.putInt(Config.FLAG_CALL_STATE, mCurrentState, mContext);
            }
        }
    }
}

修改AndroidManifest.xml

• 寫上許可權

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

• 註冊你的receive

    <receiver android:name=".receiver.PhoneStateReceive">
            <intent-filter>
                <action android:name="android.intent.action.PHONE_STATE" />
                <action android:name="android.intent.action.NEW_OUTGOING_CALL" />
            </intent-filter>
    </receiver>

總結

• 使用BoardcaseReceive來接收撥打狀態；
• 將當前的撥打狀態儲存起來；
• 要想獲得接通和結束通話的動作，必須使用當前狀態和過去狀態來判斷；
• 需要新增獲取撥打狀態的許可權；