& WindowManager.LayoutParams.INPUT_FEATURE_NO_INPUT_CHANNEL) == 0) {

String name = win.makeInputChannelName();

InputChannel[] inputChannels = InputChannel.openInputChannelPair(name);

win.setInputChannel(inputChannels[0]);

inputChannels[1].transferTo(outInputChannel);

mInputManager.registerInputChannel(win.mInputChannel, win.mInputWindowHandle);

}

}

在windowState.java中调用attach：

void attach() {

mSession.windowAddedLocked();

}

最后在Session.java中实现添加：

void windowAddedLocked() {

if (mSurfaceSession == null) {

mSurfaceSession = new SurfaceSession();

mService.mSessions.add(this);

}

mNumWindow++;

}

至此，正式建立activity的client和windowManagerService之间的联系：

ViewRootImpl 通过IWindowSession 访问 WindowManagerService

WindowManagerService通过IWindow访问ViewRootImpl