因为Android2.3以上增加了对permission android.permission.MODIFY_PHONE_STATE 的限制，2.3之前的通过反射机制调用ITelephone的能力的做法已经不适用
2.3上实现方式：
public synchronized void answerRingingCall() { // 据说该方法只能用于Android2.3及2.3以上的版本上 try { Intent localIntent1 = new Intent(Intent.ACTION_HEADSET_PLUG); localIntent1.addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY); localIntent1.putExtra("state", 1); localIntent1.putExtra("microphone", 1); localIntent1.putExtra("name", "Headset"); sendOrderedBroadcast(localIntent1, "android.permission.CALL_PRIVILEGED"); Intent localIntent2 = new Intent(Intent.ACTION_MEDIA_BUTTON); KeyEvent localKeyEvent1 = new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_HEADSETHOOK); localIntent2.putExtra("android.intent.extra.KEY_EVENT", localKeyEvent1); sendOrderedBroadcast(localIntent2, "android.permission.CALL_PRIVILEGED"); Intent localIntent3 = new Intent(Intent.ACTION_MEDIA_BUTTON); KeyEvent localKeyEvent2 = new KeyEvent(KeyEvent.ACTION_UP, KeyEvent.KEYCODE_HEADSETHOOK); localIntent3.putExtra("android.intent.extra.KEY_EVENT", localKeyEvent2); sendOrderedBroadcast(localIntent3, "android.permission.CALL_PRIVILEGED"); Intent localIntent4 = new Intent(Intent.ACTION_HEADSET_PLUG); localIntent4.addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY); localIntent4.putExtra("state", 0); localIntent4.putExtra("microphone", 1); localIntent4.putExtra("name", "Headset"); sendOrderedBroadcast(localIntent4, "android.permission.CALL_PRIVILEGED"); } catch (Exception e) { e.printStackTrace(); } }