How to navigate between screens in react native with separeate js files - class

I have react native project and I saved the home screen and details screens as oneScreen.js and two screen.js inside the src directory but there class names are different. So now I want call to them from App.js file and after a button press in home screen it should directed to details screen.how to do this using createStack navigator.

Can you try with bellow command. I am not sure it works on your structure. You should provide more screenshoot.
<Button
...
onPress = {() => this.props.navigation.navigate("ScreenName")}
/>

in App.js
import Homescreen from './onescreen';
import Detailscreen from './twoscreen';
class Homescreen extends component{
static navigationoptions={
enter code here
};
render(){
return(
<Homescreen navigation={this.props.navigation} />
);
}
}
class Detailsscreen extends component{
static navigationOptions={
enter code here
}
render(){
return(
<Detailsscreen navigation={this.props.navigation}/>
);
}
}
export default App = createStackNavigator(
{
Home:{screen:Homescreen},
Details:{screen:Detailsscn}
}
);
//you can put additional properties inside the navigationOptions
in buttonPress you can call
this.props.navigation.navigate('Home'); to navigate home
this.props.navigation.navigate('Details'); to navigate Details

Related

Ionic3 background disappears when push a new page with Tabs

I try to push a new page with tabs in my app. However, I found when I click the button (add friends), the new page popup from right side and the background page suddenly disappears. when I click back button on the top left in new page(component). you will find that the background layer only shows white, and after the new page closing completely, the welcome page shows again.
example:
you can see my code below:
Here is the code if you need: https://stackblitz.com/edit/ionic-mfc3ga
open the link in Chrome
clicking "open in new window" on the top right of the page.
In new window, open development tools(Chrome) and switch to mobile model(toggle device toolbar) and please refresh the browser.
clicking the "add friend button" on the top right.
you will see the background page(Welcome to Ionic) disappearing when the new page slides from right to left.
In addition, when you click back button on the top left in new page(component). you will find that the background layer only shows
white, and after the new page closing completely, the welcome page
shows again.
I have no idea what's wrong with my code.
Thanks Everyone
delete import { AboutPage } from '../about/about'; to AboutPage
import { Component } from '#angular/core';
import { NavController } from 'ionic-angular';
// import { AboutPage } from '../about/about'; DELETE THIS
import { ContactPage } from '../contact/contact';
import { HomePage } from '../home/home';
#Component({
selector: 'page-about',
templateUrl: 'about.html'
})
export class AboutPage {
tab1Root = HomePage;
// tab2Root = AboutPage;
tab3Root = ContactPage;
constructor(public navCtrl: NavController) {
}
}
in app.module.ts
remove: AboutPage, ContactPage, HomePage, TabsPage on =>> entryComponents
entryComponents: [
MyApp,
],
and it works well ))

Ionic2 - Alternate way to route without using injected component?

I am building a mobile app and I'd like the user to have the ability to set their starting page via a settings-page. The idea is that the user can select a page from a list of options, the setting gets stored to local-storage and later, when the user logs back in, the user is automatically taken to that page first.
I have a page-service which contains a mapping of Id's to page-components. This is what I use to find the page I want to use when I read in my user's saved start-page data.
My issue is that I have developed a cyclic-dependency that I don't think I can break without finding a way to route in Ionic2 that doesn't involve using the injected component. As far as I can tell, the only way routing is achieved in Ionic2 is with the NavController.push(component) or Nav.setRoot(component).
PageService.ts
import {Injectable} from "#angular/core";
import {HomePage} from "../pages/home/home";
import {SettingsPage} from "../pages/settings/settings";
import {CartPage} from "../pages/cart/cart";
#Injectable()
export class PageService {
public pages = [
{
id: "HOME",
component: HomePage
}, {
id: "SETTINGS",
component: SettingsPage
}, {
id: "CART",
component: CartPage
}
];
constructor() {
}
getPageById(id: string) {
return this.pages.find(page => (page.id === id));
}
}
settings.ts:
My SettingsPage component has the PageService injected so that it can get access to get the list of pages. This is where my cyclical dependency occurs. The SettingsPage is injecting PageService which has a reference to SettingsPage in it.
import {Component} from "#angular/core";
import {PageService} from "../../providers/page-service";
import {UserService} from "../../providers/user-service";
#Component({
selector: "page-settings",
templateUrl: "settings.html",
})
export class SettingsPage {
startPages = [];
constructor(private pageService: PageService, private userService: UserService) {
this.startPages = this.pageService.getStartPages();
}
}
settings.html:
Just a simple list with a card to output the selection.
<ion-content padding>
<ion-list>
<ion-card padding>
<ion-card-title>Starting Page</ion-card-title>
<ion-item>
<ion-select [(ngModel)]="userService.activeUser.startPage">
<ion-option *ngFor="let page of startPages" value="{{page.id}}">
{{page.id}}
</ion-option>
</ion-select>
</ion-item>
</ion-card>
</ion-list>
</ion-content>
...and finally, when the app starts up and I want to automatically go to my start page I execute the following:
const startPage = this.pageService.getPageById(this.userService.activeUser.startPage);
this.nav.setRoot(startPage.component);
Updated answer
Use forward ref in the SettingsPage constructor..
constructor(#Inject(forwardRef(() => PageService)) private pageService: PageService) {
this.startPages = this.pageService.getStartPages();
}
Old Answer - not appropriate because angular should be handling the instantiation of services through injection. "new"ing is a bad idea (but it did work).
I changed how the PageService was loaded in the SettingsPage and the cyclical dependency was resolved. I moved the PageService code out of the constructor and put it into the ngAfterViewInit() function. Now the PageService is only instantiated when the view is loaded.
ngAfterViewInit(){
this.pageService = new PageService();
this.startPages = this.pageService.getStartPages();
}

Dynamically rendering react components

I'm new to reactjs and I'm having a hell of a time understanding this bug.
I've read this, and it seems like the solution is there but I'm drawing a blank on how to implement this correctly:
https://facebook.github.io/react/docs/jsx-in-depth.html#user-defined-components-must-be-capitalized
I am trying to render components based on classNames of clicked elements. The classNames match to component names. When I click an element it calls a function that sets the state of my app to that elements className. I then render the component based on the new state.
When testing, if I place the component directly into my app (not rendering the component name dynamically), it works just fine. But when i render the component name dynamically react thinks it's a built-in DOM element and doesn't render properly at all.
In this image you can see both components, rendered next to each other:
both components, first directly added, and the second with the name rendered dynamically
here is my app component code that is rendering everything:
import React, { Component } from 'react';
import logo from '../logo.svg';
import '../css/App.css';
import menus from '../menus';
import MainNav from './MainNav';
import Products from './Products';
import Demos from './Demos';
import Industry from './Industry';
import Customers from './Customers';
import Trials from './Trials';
import Contact from './Contact';
import Newsroom from './Newsroom';
import About from './About';
import Home from './Home';
class App extends Component {
constructor() {
super();
this.chooseComponent = this.chooseComponent.bind(this);
this.state = {
allMenus: menus,
componentMenu: menus,
//sets initial component to load, changes on each click to the clicked component
clickedComponent: Home
};
}
chooseComponent(event) {
//save the classname of the menu i click
var clickedComp = event.target.className;
//saves a reference to a json object for later use
var menu = menus[clickedComp];
//adds those two vars to the state
this.setState({
componentMenu: menu,
clickedComponent: clickedComp
});
}
render() {
//saves a var for rendering the currently clicked component
var ActiveComponent = this.state.clickedComponent;
return (
<div className="App">
<MainNav choose={this.chooseComponent}/>
//renders the components directly without issue
<Products menuData={this.state.componentMenu} />
//renders the component dynamically with problems
<ActiveComponent menuData={this.state.componentMenu} />
</div>
);
}
}
export default App;
here is and example of one of my component being rendered in the App that's giving problems:
import React from 'react';
import products from '../products';
import ProductsMenu from './ProductsMenu';
import Platform from './Platform';
import Applications from './Applications';
import ExMachina from './ExMachina';
import ProductsHome from './ProductsHome';
import Submenu from './Submenu';
import menus from '../menus';
class Products extends React.Component {
constructor() {
super();
this.showContent=this.showContent.bind(this);
this.state = {
productsOverview: products,
content: <ProductsHome />
}
}
render(props) {
return (
<div className="content">
{this.state.content}
</div>
);
}
}
export default Products;

Changing the document title in React?

I'm trying to update the title of the document in a React app. I have very simple needs for this. The title is essentially used to put the Total component on display even when you're on a different tab.
This was my first instinct:
const React = require('react');
export default class Total extends React.Component {
shouldComponentUpdate(nextProps) {
//otherstuff
document.title = this.props.total.toString();
console.log("Document title: ", document.title);
return true;
}
render() {
document.title = this.props.total;
return (
<div className="text-center">
<h1>{this.props.total}</h1>
</div>
);
}
}
I thought this would just update the document.title every time this component was rendered, but it doesn't appear to do anything.
Not sure what I'm missing here. Probably something to do with how React runs this function - maybe somewhere that the document variable isn't available?
EDIT:
I'm starting a bounty for this question, as I still haven't found any solution. I've updated my code to a more recent version.
A weird development is that the console.log does print out the title I'm looking for. But for some reason, the actual title in the tab isn't updating. This issue is the same across Chrome, Safari, and Firefox.
I now use react-helmet for this purpose, as it allows to customize different meta tags and links, and it also supports SSR.
import { Helmet } from 'react-helmet'
const Total = () => (
<div className="text-center">
<Helmet>
<meta charSet="utf-8" />
<title>{this.props.total}</title>
</Helmet>
<h1>{this.props.total}</h1>
</div>
)
Original answer: there's actually a package by gaeron for this purpose, but in a declarative way:
import React, { Component } from 'react'
import DocumentTitle from 'react-document-title'
export default class Total extends Component {
render () {
return (
<DocumentTitle title={this.props.total}>
<div className='text-center'>
<h1>{this.props.total}</h1>
</div>
</DocumentTitle>
)
}
}
Inside your componentDidMount() function in App.js (or wherever), simply have:
componentDidMount() {
document.title = "Amazing Page";
}
The reason this works is anywhere in your react project you have access to the Js global scope. Go ahead and type window in your sites console. Basically everything there you will be able to access in your React project.
I think webpack-dev-server runs in an iframe mode by default:
https://webpack.github.io/docs/webpack-dev-server.html#iframe-mode
So that might be why your attempts to set the title are failing. Try setting the inline option to true on webpack-dev-server, if you haven't already.
If the react-document-title package isn't working for you, the quick'n'dirty way to do that would be in a lifecycle method, probably both componentDidMount and componentWillReceiveProps (you can read more about those here):
So you would do something like:
const React = require('react');
export default class Total extends React.Component {
// gets called whenever new props are assigned to the component
// but NOT during the initial mount/render
componentWillReceiveProps(nextProps) {
document.title = this.props.total;
}
// gets called during the initial mount/render
componentDidMount() {
document.title = this.props.total;
}
render() {
return (
<div className="text-center">
<h1>{this.props.total}</h1>
</div>
);
}
}
There is a better way of dynamically changing document title with react-helmet package.
As a matter of fact you can dynamically change anything inside <head> tag using react-helmet from inside your component.
const componentA = (props) => {
return (
<div>
<Helmet>
<title>Your dynamic document/page Title</title>
<meta name="description" content="Helmet application" />
</Helmet>
.....other component content
);
}
To change title, meta tags and favicon dynamically at run time react-helmet provides a simple solution. You can also do this in componentDidMount using the standard document interface. In the example below I am using the same code for multiple sites, so helmet is looking for favicon and title from an environment variable
import { Helmet } from "react-helmet";
import { getAppStyles } from '../relative-path';
import { env } from '../relative-path';
<Helmet>
<meta charSet="utf-8" />
<title>{pageTitle[env.app.NAME].title}</title>
<link rel="shortcut icon" href={appStyles.favicon} />
</Helmet>

wicket:link and pages with #AuthorizeInstantiation

I have a navigation bar like:
<nav>
<ul>
<wicket:link>
<li>Page1</li>
<li>Page2</li>
<li>Page3</li>
</wicket:link>
</ul>
</nav>
This panel works really well (with the matching css).
But, Page3 is only accessible for users logged in.
#AuthorizeInstantiation("SIGNED_IN")
public class Page3 extends MyPage {
// ...
}
When a user is logged in, everything is as expected.
Navigation: Page1 Page2 Page3
But when the user is not logged in, I expect Page3 not to be part of the navigation bar (because it is not accessible).
Navigation: Page1 Page2
How can I do this? TIA!
Add your links using wicket. Then use IAuthorizationStrategy to check if you can instantiate the page the link refers to. Hide the link if not:
IAuthorizationStrategy strategy = getApplication().getSecuritySettings().getAuthorizationStrategy();
Link<?> page1link = new Link<Void>("page1") {
#Override
public void onClick() {
setResponsPage(Page1.class);
}
}
page1link.add(new Label("page1linklabel","Page 1"));
page1link.setVisible(strategy.isInstantiationAuthorized(Page1.class));
add(page1link);
The html for your link then looks like this:
<span wicket:id="page1linklabel"></span>