state

问题 I'd like to use NGXS to open modal which will set column visibility for datatable. Here is my code: state.ts file: @Action(OpenColumnModal) openColumnModal(ctx: StateContext<FeedStateModel>) { const state = ctx.getState(); const allCols = state.allColumns; return this.modalService.openColumnVisibilityModal(allCols).pipe(tap((result) => { ctx.setState({ ...state, allColumns: result, userColumns: result.filter(col => col.visible) }); }) } modal.service.ts: openColumnVisibilityModal(columns):

问题 I'd like to use NGXS to open modal which will set column visibility for datatable. Here is my code: state.ts file: @Action(OpenColumnModal) openColumnModal(ctx: StateContext<FeedStateModel>) { const state = ctx.getState(); const allCols = state.allColumns; return this.modalService.openColumnVisibilityModal(allCols).pipe(tap((result) => { ctx.setState({ ...state, allColumns: result, userColumns: result.filter(col => col.visible) }); }) } modal.service.ts: openColumnVisibilityModal(columns):

问题 This question already has answers here : Strange behavior of React hooks: delayed data update (3 answers) Closed 22 days ago . In the React Native App, after I click the toggle button, the function _toggleServerSwitch gets triggered. Then I change the state serverSwitchValue to the same value as x . Expected : serverSwitchValue and x should have the same value when console.log() . Actual : When console.log(), the two variables have different values. It seems that the program works, but at the

问题 So coming from an Angular/AngularJS background, you have states, and each state is a separate page. E.g. in a social network you can have a state with your feed, a state with a list of your friends, or a state to see a profile etc. Pretty straightforward. Not so much in React for me. So let's say I have an application with 2 pages: a list of products and a single product view. What would be the best way to switch between them? The simplest solution is to have an object which has a stateName

问题 So coming from an Angular/AngularJS background, you have states, and each state is a separate page. E.g. in a social network you can have a state with your feed, a state with a list of your friends, or a state to see a profile etc. Pretty straightforward. Not so much in React for me. So let's say I have an application with 2 pages: a list of products and a single product view. What would be the best way to switch between them? The simplest solution is to have an object which has a stateName

问题 I have an object Foo which can be configured using a fragment ( FooFragment ). The Foo class contains a static reference to FooFragment and the method public Fragment getConfigurationFragment() ; this method assigns the current object to the FooFragment and returns it. public class Foo{ private static FooFragment fooFragment = new FooFragment(); public Fragment getConfigurationFragment(){ fooFragment.setObject(this); return fooFragment; } //various getters and setters } FooFragment is roughly

问题 I have an object Foo which can be configured using a fragment ( FooFragment ). The Foo class contains a static reference to FooFragment and the method public Fragment getConfigurationFragment() ; this method assigns the current object to the FooFragment and returns it. public class Foo{ private static FooFragment fooFragment = new FooFragment(); public Fragment getConfigurationFragment(){ fooFragment.setObject(this); return fooFragment; } //various getters and setters } FooFragment is roughly

问题 How can I convert the regular expression a*b* to a finite state machine? I am just starting out, and have no idea how to start. 回答1: Think about it. a*b* means a 0 or more times then b 0 or more times. Building a state transition table... Transitions 0 - empty 1 - next a 2 - next b 3 - next not ( a or b ) State / Transitions S | T | S S | 0 | Y S | 1 | a S | 2 | b S | 3 | N a | 0 | Y a | 1 | a a | 2 | b a | 3 | N b | 0 | Y b | 1 | N b | 2 | b b | 3 | N States S - start Y - end - matches N -

问题 Example: class UserStorage { public function addUser(User $user) { //saves to db } } class User { public function setName($name); } What if I add a user to the user storage and later change that user object? In this case you might argue that user objects only should be stored on __destruct. But sometimes this isn't an option (eg imagine the user is displayed and updated afterwards). 回答1: I agree with Peter, the above model seems a little quirky to me and I would recommend against implicit

问题 Slight issue here which I think is relatively simple to solve but I can't quite get my head around. I'm quite new to React. I've decided to make a small sample app which just takes the input from two fields, saves them to Firebase and outputs those values on the page. It works completely fine in terms of submitting data and retrieving it, but when I click the submit button to add the data to Firebase it seems to duplicate the data stored in the state and render them twice: Parent Component: