dart

问题 I'm trying to navigate to a new screen using ListViewBuilder and Cards. I currently have my named route set so that it accepts an index of my parsed json model. So the question is how do I pass the 'name' (String) parameter, as well as, 'nextEpisodes' (ListString) and 'prevEpisodes' (ListString). I'd like to access all of these variables on the next screen. Thanks in advance. ListView.builder( shrinkWrap: true, itemCount: slist.length, itemBuilder: (context, index) { print(slist[index]

问题 I'm trying to navigate to a new screen using ListViewBuilder and Cards. I currently have my named route set so that it accepts an index of my parsed json model. So the question is how do I pass the 'name' (String) parameter, as well as, 'nextEpisodes' (ListString) and 'prevEpisodes' (ListString). I'd like to access all of these variables on the next screen. Thanks in advance. ListView.builder( shrinkWrap: true, itemCount: slist.length, itemBuilder: (context, index) { print(slist[index]

问题 I'm trying to navigate to a new screen using ListViewBuilder and Cards. I currently have my named route set so that it accepts an index of my parsed json model. So the question is how do I pass the 'name' (String) parameter, as well as, 'nextEpisodes' (ListString) and 'prevEpisodes' (ListString). I'd like to access all of these variables on the next screen. Thanks in advance. ListView.builder( shrinkWrap: true, itemCount: slist.length, itemBuilder: (context, index) { print(slist[index]

问题 I'm trying to navigate to a new screen using ListViewBuilder and Cards. I currently have my named route set so that it accepts an index of my parsed json model. So the question is how do I pass the 'name' (String) parameter, as well as, 'nextEpisodes' (ListString) and 'prevEpisodes' (ListString). I'd like to access all of these variables on the next screen. Thanks in advance. ListView.builder( shrinkWrap: true, itemCount: slist.length, itemBuilder: (context, index) { print(slist[index]

问题 if(country1!=null) { country1="Turkey"; } else { country1= "ABD"; } 回答1: Ternary operators use three operands: A condition followed by a ? , followed by an expression to evaluate if the condition is 'truthy', followed by a : , followed by an expression to evaluate if the condition is falsey . So in your case, what you'd want to do is this: country1 = country1 != null ? 'Turkey' : 'ABD'; EDIT: You seem a little confused about ?? operator. ?? is called Null Coalescing operator x = x ?? 'foo';

问题 if(country1!=null) { country1="Turkey"; } else { country1= "ABD"; } 回答1: Ternary operators use three operands: A condition followed by a ? , followed by an expression to evaluate if the condition is 'truthy', followed by a : , followed by an expression to evaluate if the condition is falsey . So in your case, what you'd want to do is this: country1 = country1 != null ? 'Turkey' : 'ABD'; EDIT: You seem a little confused about ?? operator. ?? is called Null Coalescing operator x = x ?? 'foo';

问题 I've got a backend running rocket.rs which my flutter web app sends a request to, but it can't get past the OPTIONS response. I have tried adding CORS (rocket_cors) to the backend and having a options response, but it still sends back: Error: XMLHttpRequest error. dart:sdk_internal 124039:30 get current packages/http/src/browser_client.dart.lib.js 214:124 <fn> I have added the following to my rocket project: #[options("/")] fn send_options<'a>(path: PathBuf) -> Response<'a> { let mut res =

问题 I've got a function that should accept two diffrent data types as input: vec3 add(vec3 vec){ this.x += vec.x; this.y += vec.y; this.z += vec.z; return this; } vec3 add(num scalar){ this.x += scalar; this.y += scalar; this.z += scalar; return this; } but this returns an error: The name 'add' is already defined Is there a way to make this work in Dart? I know that types are optional but I would like to know whether there is a way. 回答1: Dart doesn't allow function/method overloading. You can

问题 I've got a function that should accept two diffrent data types as input: vec3 add(vec3 vec){ this.x += vec.x; this.y += vec.y; this.z += vec.z; return this; } vec3 add(num scalar){ this.x += scalar; this.y += scalar; this.z += scalar; return this; } but this returns an error: The name 'add' is already defined Is there a way to make this work in Dart? I know that types are optional but I would like to know whether there is a way. 回答1: Dart doesn't allow function/method overloading. You can

问题 I've got a function that should accept two diffrent data types as input: vec3 add(vec3 vec){ this.x += vec.x; this.y += vec.y; this.z += vec.z; return this; } vec3 add(num scalar){ this.x += scalar; this.y += scalar; this.z += scalar; return this; } but this returns an error: The name 'add' is already defined Is there a way to make this work in Dart? I know that types are optional but I would like to know whether there is a way. 回答1: Dart doesn't allow function/method overloading. You can