Android 在MediaRouter或DisplayManager中找不到JellyBean外部显示器

我正在尝试使用JellyBean中的Presenter功能在额外的大屏幕上显示自定义图形。我使用兼容MHL的HDMI适配器（microUSB->HDMI）连接。下面是我试图检测外部显示的代码。出于某种原因-我确实在外部显示器上获得了输出，但DisplayManager不会检测到外部显示器。我想知道这是否与适配器有关，或者如果我直接用HDMI电缆将手机连接到外部显示器，情况会是这样

我的日志：

我的代码块：

@SuppressLint("NewApi")
private void updatePresentation() {
    // Get the current route and its presentation display.
    Log.d(EXTRA_DISPLAY_TAG, "Inside updatePresentation() call...");

    MediaRouter.RouteInfo route = mediaRouter.getSelectedRoute(MediaRouter.ROUTE_TYPE_LIVE_VIDEO);

    Log.d(EXTRA_DISPLAY_TAG, "Route name: " + route.getName() + " , route status: " + route.getStatus());
    Display externalDisplay = null;
    if(route != null && route.getName().equals("HDMI")){
        externalDisplay = route.getPresentationDisplay();
        if(externalDisplay == null){ //Maybe not ready...
            Log.d(EXTRA_DISPLAY_TAG, "Waiting for external display to become ready...");
            SystemClock.sleep(2000);
            DisplayManager displayManager = (DisplayManager)getSystemService(DISPLAY_SERVICE);
            Display[] presentationDisplays = displayManager.getDisplays(DisplayManager.DISPLAY_CATEGORY_PRESENTATION);
            if(null == presentationDisplays || presentationDisplays.length == 0){
                Log.d(EXTRA_DISPLAY_TAG, "Didn't find any presentation displays by category...");
            }else{
                externalDisplay = presentationDisplays[0]; //OK: Take first
            }
            //Try to manually select display...
            if(externalDisplay == null){
                Display[] allDisplays = displayManager.getDisplays();
                for(int i=0; i<allDisplays.length; i++){
                    Log.d(EXTRA_DISPLAY_TAG, "Detected display  "+(i+1)+ " : " + allDisplays[i].getName());
                }


                //externalDisplay = allDisplays[0]; //FIXME: Take by some criteria...
            }
        }
    }

    if(externalDisplay != null){
        Log.i(EXTRA_DISPLAY_TAG, "Detected external display...");
        Point size = new Point();
        externalDisplay.getSize(size);
        int width = size.x;
        int height = size.y;
        Log.i(EXTRA_DISPLAY_TAG, "External display resolution: " + width + "px x " + height + "px");
    }

    // Dismiss current presentation if display changes
    if(quantumPresentation != null && quantumPresentation.getDisplay() != externalDisplay){

        Log.i(EXTRA_DISPLAY_TAG, "Leaving presentation because current route no longer has a presentation display.");
        quantumPresentation.dismiss();
        quantumPresentation = null;
    }

    // Show new presentation if needed
    if(quantumPresentation == null && externalDisplay != null) {
        Log.i(EXTRA_DISPLAY_TAG, "Showing presentation on display: "  + externalDisplay);
        quantumPresentation = new QuantumPresentation(this, externalDisplay);
        quantumPresentation.setOnDismissListener(onPresentationDismissListener);            
        try{
            Log.i(EXTRA_DISPLAY_TAG, "Starting additional display presentation...");
            quantumPresentation.show();
        } catch (WindowManager.InvalidDisplayException ex){
            Log.w(EXTRA_DISPLAY_TAG, "Couldn't show presentation! External display was removed in the meantime!", ex);
            quantumPresentation = null;
        }

    }
    // Update the contents playing in activity...
    updateContents();


}

@SuppressLint（“NewApi”）
私有void updatePresentation（）{
//获取当前路线及其演示文稿显示。
Log.d（额外的显示标签，“Inside updatePresentation（）调用…”）；
MediaRouter.RouteInfo route=MediaRouter.getSelectedRoute（MediaRouter.route\u TYPE\u LIVE\u VIDEO）；
Log.d（额外的显示标签，“路由名称：“+Route.getName（）+”，路由状态：“+Route.getStatus（）”）；
Display externalDisplay=null；
if（route！=null&&route.getName（）.equals（“HDMI”））{
externalDisplay=route.getPresentationDisplay（）；
如果（externalDisplay==null）{//可能还没有准备好。。。
Log.d（额外的显示标签，“等待外部显示准备就绪…”）；
SystemClock.sleep（2000年）；
DisplayManager DisplayManager=（DisplayManager）getSystemService（显示服务）；
Display[]presentationDisplays=displayManager.getDisplays（displayManager.Display\u CATEGORY\u PRESENTATION）；
if（null==presentationDisplays | | presentationDisplays.length==0）{
Log.d（额外的显示标签，“未按类别找到任何演示文稿显示…”）；
}否则{
externalDisplay=presentationDisplays[0]；//确定：先执行
}
//尝试手动选择显示。。。
if（externalDisplay==null）{
Display[]allDisplays=displayManager.getDisplays（）；
对于（int i=0；i），Galaxy Nexus不支持多个独立的显示器，正如已经报道的那样：