mobile-application

问题 I am using flutter and firebase to create a mobile app. I have 2 collections on my firestore and i wanna read all documents in a the collection "posts". However, when I do that, an error saying the getter "documents" was called on null. Widget getContent(BuildContext context) { return StreamBuilder<QuerySnapshot>( stream: Firestore.instance.collection("posts").snapshots(), builder: (context, snap) { return CarouselSlider( enlargeCenterPage: true, height: MediaQuery.of(context).size.height,

问题 I'm new to flutter and I'm working on an App that have multiple screens. I would like to know to stop flutter from creating multiple screens of the same route, for example I have Page 1 and Page 2 , if I click on the button to navigate to Page 2 and clicked again on the same button the application will push a new screen of Page 2 and i will have it twice and if I click on the return button it will send me back to the first created Page 2 is there a way to create every page only once and then

问题 I'm new to flutter and I'm working on an App that have multiple screens. I would like to know to stop flutter from creating multiple screens of the same route, for example I have Page 1 and Page 2 , if I click on the button to navigate to Page 2 and clicked again on the same button the application will push a new screen of Page 2 and i will have it twice and if I click on the return button it will send me back to the first created Page 2 is there a way to create every page only once and then

来源： https://stackoverflow.com/questions/40016361/nsurlsession-request-and-response

来源： https://stackoverflow.com/questions/57177064/is-it-necessary-to-install-android-studio-for-flutter-or-what-can-be-replacement

来源： https://stackoverflow.com/questions/57177064/is-it-necessary-to-install-android-studio-for-flutter-or-what-can-be-replacement

问题 I have a web socket server on desktop and client on iPhone device. I would like to communicate with them using USB rather than any network. I have implemented it on android using adb reverse but not able to find any solution for iOS. I have tried to implement it using usbmuxd and iproxy but they only does port forwarding not the reverse forwarding.I would really appreciate some help on it. 回答1: Not sure if it will solve your problem, because I did not use the library, but some time ago I've

问题 I have a web socket server on desktop and client on iPhone device. I would like to communicate with them using USB rather than any network. I have implemented it on android using adb reverse but not able to find any solution for iOS. I have tried to implement it using usbmuxd and iproxy but they only does port forwarding not the reverse forwarding.I would really appreciate some help on it. 回答1: Not sure if it will solve your problem, because I did not use the library, but some time ago I've

问题 The approach involved with the two items in the title of this post appear to conflict with one another and are very hard to test, and it's these edge cases that result in unhappy customers when their purchased product stops working. A lot of the discussions on Stack Overflow are 2+ years old, inconclusive and reference the deprecated AIDL library rather than Google Play Billing Service. I want to make sure a user has offline access to a premium version of my Android App which is purchased via

问题 The approach involved with the two items in the title of this post appear to conflict with one another and are very hard to test, and it's these edge cases that result in unhappy customers when their purchased product stops working. A lot of the discussions on Stack Overflow are 2+ years old, inconclusive and reference the deprecated AIDL library rather than Google Play Billing Service. I want to make sure a user has offline access to a premium version of my Android App which is purchased via