Flutter

问题 I am making an app, which contains two basic classes let's say Class1 and Class2 . And in Class1 I stored List<Class2> as attribute with other attributes. My question is how to store List<Class2> if I store some object of Class1 in sqflite database. Is there a way that I can store a List of Class2 objects in a single column of the database. 回答1: You can serialize it to json and save the string. Then when you read it you can parse it back to an Object 来源： https://stackoverflow.com/questions

问题 I am making an app, which contains two basic classes let's say Class1 and Class2 . And in Class1 I stored List<Class2> as attribute with other attributes. My question is how to store List<Class2> if I store some object of Class1 in sqflite database. Is there a way that I can store a List of Class2 objects in a single column of the database. 回答1: You can serialize it to json and save the string. Then when you read it you can parse it back to an Object 来源： https://stackoverflow.com/questions

问题 I am making an app, which contains two basic classes let's say Class1 and Class2 . And in Class1 I stored List<Class2> as attribute with other attributes. My question is how to store List<Class2> if I store some object of Class1 in sqflite database. Is there a way that I can store a List of Class2 objects in a single column of the database. 回答1: You can serialize it to json and save the string. Then when you read it you can parse it back to an Object 来源： https://stackoverflow.com/questions

问题 I'm quite new to Firebase Flutter. I'm developing a mobile application to share books among others. In firebase firestore, I have 'users' collections which contain all the user data with unique id I have 'books' collection which contain all the book data with unique id created automatically Also I have 'global' collection with single document with one integer field called 'bookcount'. Users can can have many books. Now I want to create a another unique id field for book. idea is to have

问题 I have been trying to load static data into ListViewBuilder I successfully achieved the functionality using the same code given below but now it ain't working. LIST VIEW BUILDER ListView.builder( scrollDirection: Axis.horizontal, shrinkWrap: true, itemCount: allProducts.length==null ? 0 : allProducts.length, itemBuilder: (BuildContext ctxt, int index) { return new CustomCardProduct( product:allProducts[index], onPress: (){ ); }, ); }, ), STATIC DATA AND CLASS STORED IN USER.DART FILE. List

问题 I have been trying to load static data into ListViewBuilder I successfully achieved the functionality using the same code given below but now it ain't working. LIST VIEW BUILDER ListView.builder( scrollDirection: Axis.horizontal, shrinkWrap: true, itemCount: allProducts.length==null ? 0 : allProducts.length, itemBuilder: (BuildContext ctxt, int index) { return new CustomCardProduct( product:allProducts[index], onPress: (){ ); }, ); }, ), STATIC DATA AND CLASS STORED IN USER.DART FILE. List

问题 I'm quite new to Firebase Flutter. I'm developing a mobile application to share books among others. In firebase firestore, I have 'users' collections which contain all the user data with unique id I have 'books' collection which contain all the book data with unique id created automatically Also I have 'global' collection with single document with one integer field called 'bookcount'. Users can can have many books. Now I want to create a another unique id field for book. idea is to have

问题 I'm fairly new to Dart and Flutter, and I'm having trouble to overwrite an existing assets image from a source image. My attempt: try { File localFile = File('assets/images/myImage.png'); localFile.writeAsBytesSync(originFile.readAsBytesSync()); catch (e) { log(e.toString()); } I get: [log] FileSystemException: Cannot open file, path = 'assets/images/myImage.png' (OS Error: No such file or directory, errno = 2) I did define the assets folder in pubspec.yaml : assets: - assets/images/ Ok, so I

问题 I'm fairly new to Dart and Flutter, and I'm having trouble to overwrite an existing assets image from a source image. My attempt: try { File localFile = File('assets/images/myImage.png'); localFile.writeAsBytesSync(originFile.readAsBytesSync()); catch (e) { log(e.toString()); } I get: [log] FileSystemException: Cannot open file, path = 'assets/images/myImage.png' (OS Error: No such file or directory, errno = 2) I did define the assets folder in pubspec.yaml : assets: - assets/images/ Ok, so I

问题 I'm fairly new to Dart and Flutter, and I'm having trouble to overwrite an existing assets image from a source image. My attempt: try { File localFile = File('assets/images/myImage.png'); localFile.writeAsBytesSync(originFile.readAsBytesSync()); catch (e) { log(e.toString()); } I get: [log] FileSystemException: Cannot open file, path = 'assets/images/myImage.png' (OS Error: No such file or directory, errno = 2) I did define the assets folder in pubspec.yaml : assets: - assets/images/ Ok, so I