@Override public void switchHoldingAndActive() throws CallStateException { if (DBG) log("dialInternal: switch fg and bg"); synchronized (SipPhone.class) { mForegroundCall.switchWith(mBackgroundCall); if (mBackgroundCall.getState().isAlive()) mBackgroundCall.hold(); if (mForegroundCall.getState().isAlive()) mForegroundCall.unhold(); } }