Android9 双屏异显实现方式思路

adb shell am start -n com.android.demo/com.android.demo.MainActivity --display 1
adb shell am start -n com.android.demo/com.android.demo.MainActivity --user 0 --display 1

MediaRouter mediaRouter = (MediaRouter) context.getSystemService(Context.MEDIA_ROUTER_SERVICE);
MediaRouter.RouteInfo route = mediaRouter.getSelectedRoute();---先获取RouteInfo，再获取Display
//MediaRouter.RouteInfo route = mediaRouter.getSelectedRoute(ROUTE_TYPE_USER)
if(route != null) {
     Display presentationDisplay = route.getPresentationDisplay();
     if (presentationDisplay != null) {
           Presentation presentation = new MyPresentation(context, presentationDisplay);
           presentation.show();
     }
}
DisplayManager mDisplayManager = getSystemService(Context.DISPLAY_SERVICE);
Display displays = mDisplayManager.getDisplay(1);

ActivityOptions options = ActivityOptions.makeBasic();
options.setLaunchDisplayId(1); //这里一直display0是第一块屏；display1是第二块屏
Intent secondIntent = new Intent();
ComponentName cn= new ComponentName("com.android.demo"，"com.android.demo.SecondActivity");
secondIntent .setComponent(cn);
//该句很重要，不添加则无法推送到副屏
secondIntent.addFlags(Intent.FLAG_ACTIVITY_MULTIPLE_TASK|Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(secondIntent, options.toBundle());
使用ActivityOptions指定显示屏幕
为Intent增加标志Intent.FLAG_ACTIVITY_MULTIPLE_TASK|Intent.FLAG_ACTIVITY_NEW_TASK