React Native - Modal - Dynamic Max Height - reactjs

I'm using a modal within a view - which contains a form. The form is longer than the viewport - so, the content is taking up the height of the page and scrolling out of view.
Can anyone advise on the best approach for dynamic height?
currently i'm using the following approach, but doesnt work if phone orientation switched and i'm sure there must be a better solution?
heightScreen = () => {
return Dimensions.get('window').height - 150;
}
<Modal
isVisible={this.props.showModal}
animationInTiming={500}
backdropColor={'#f79431'}
style={{ marginVertical:50, maxHeight: this.heightScreen()}}
>

import {useEffect, useState} from 'react';
import {Dimensions} from 'react-native';
export const useOrientation = () => {
const [orientation, setOrientation] = useState("PORTRAIT");
useEffect(() => {
Dimensions.addEventListener('change', ({ window:{ width, height } }) => {
setOrientation(width < height ? "PORTRAIT" : "LANDSCAPE")
})
}, []);
return orientation;
}
You can add this function as a helper to detect the orientation (portrait/landscape) and based on that to apply the correct height.

Related

Two React useEffect hooks accessing the window onscroll?

I am new to React dev so this may be something simple I am missing with hooks.
Using a template, I have used a header bar which shrinks in height if you scroll down in the page far enough (i.e it is only at max height if you scroll to the top).
I have been customising a sidebar to go along with the headerbar, and I'm trying to get the items within it to also move up when the bottom of the headerbar moves up.
The app bar uses a pre-made function:
import { useState, useEffect } from 'react';
// ----------------------------------------------------------------------
export default function useOffSetTop(top: number) {
const [offsetTop, setOffSetTop] = useState(false);
const isTop = top || 100;
useEffect(() => {
window.onscroll = () => {
if (window.pageYOffset > isTop) {
setOffSetTop(true);
} else {
setOffSetTop(false);
}
};
return () => {
window.onscroll = null;
};
}, [isTop]);
return offsetTop;
}
Then you can just import it, assign a constant bool to useOffSetTop(HEADER.DASHBOARD_DESKTOP_HEIGHT) and base the layout on the state of that const.
In the app bar it controls the height, so in the nav bar I made it control he height of an empty .
It does work, but the app bar stops working.
I do have hot-reload on and if I make a change to the app bar it starts working but the nav bar stops working.
I guess it is just because whichever loads last is the one which binds something to window.onscroll and the other is wiped.
I am just wondering how I could change this function or restructure the code so that this could be imported by multiple components on the same page - possibly without having to just import it higher up and pass the true/false value down through the components?
The issue is that you are actually "overriding" the onScroll function (or replacing it) instead of listening for the event.
by doing this
window.onScroll = null;
you are effectively overriding the onScroll function to do nothing.
Best to listen for the onscroll event.
import { useState, useEffect } from 'react';
export default function useOffSetTop(top: number) {
const [offsetTop, setOffSetTop] = useState(false);
const isTop = top || 100;
const handleOnScroll = () => {
if (window.pageYOffset > isTop) {
setOffSetTop(true);
} else {
setOffSetTop(false);
}
}
useEffect(() => {
window.addEventListener('scroll', handleOnScroll )
return () => {
window.removeEventListener('scroll', handleOnScroll)
};
}, [isTop, handleOnScroll]);
return offsetTop;
}

how do i make echarts resize together with the react-grid-layout?

I am using ResponsiveGridLayout, React-Grid-Layout in my application, and I am using echarts as grid items.
The drag and drop works fine, but when i resize the grid item, the chart did not resize together with it. I have tried implementing the onLayoutchange properties, but it is not working.
can someone can help me out here
this is my codesandbox that reproduce the issue
I was able to achieve this, at least when modifying grid items width (not height yet...), by using this hook, then in your chart component :
[...]
const chartRef = useRef<HTMLDivElement>();
const size = useComponentSize(chartRef);
useEffect(() => {
const chart = chartRef.current && echarts.getInstanceByDom(chartRef.current);
if (chart) {
chart.resize();
}
}, [size]);
[...]
return <div ref={chartRef}></div>;
...so your chart will resize when the grid item is resized. I'm not sure about that, still a WIP for me but it works.
Extract this as a custom hook
You can create useEchartResizer.ts, based on #rehooks/component-size :
import useComponentSize from '#rehooks/component-size';
import * as echarts from 'echarts';
import React, { useEffect } from 'react';
export const useEchartResizer = (chartRef: React.MutableRefObject<HTMLDivElement>) => {
const size = useComponentSize(chartRef);
useEffect(() => {
const chart = chartRef.current && echarts.getInstanceByDom(chartRef.current);
if (chart) {
chart.resize();
}
}, [chartRef, size]);
};
Then use it in the component which holds the chart :
export const ComponentWithChart = (props): React.ReactElement => {
const chartRef = useRef<HTMLDivElement>();
useEchartResizer(chartRef);
useEffect(() => {
const chart = echarts.init(chartRef.current, null);
// do not set chart height in options
// but you need to ensure that the containing div is not "flat" (height = 0)
chart.setOption({...} as EChartsOption);
});
return (<div ref={chartRef}></div>);
});
So each time the div is resized, useEchartResizer will trigger a chart.resize(). Works well with react-grid-layout.

How to detect certain scroll position with framer-motion?

When scrollTop is equal to 500px, I want to trigger an animation on a div with position fixed. Is there a way to do this in framer-motion. I only find solution that propose when element is in viewport. But my div is always in the viewport, because it has a fixed position. I need a build in scroll position watcher.
sandbox
import { useInView } from "react-intersection-observer";
import { motion, useAnimation } from "framer-motion";
this is kind of old already but here is the answer.
import { useViewportScroll } from "framer-motion";
const Nav = () => {
const { scrollY } = useViewportScroll();
scrolly.onChange(y => {
// y = scroll position
//Do Something
})
}
const { scrollY } = useViewportScroll();
scrollY.onChange(y => {
console.log('y ', y)
})
just a slight typo :)

React execute script if window width

I have a button in React that executes a function onClick. I want to get rid of the button, and instead programmatically execute the function if window width < 1000px.
A restriction is that I can not add a plugin.
Here's what the code looks like...
// Do I need useState, useEffect?
import React, { PureComponent } from "react";
class MainNav extends PureComponent {
state = {
// Does something go here? What goes here and how do I use
// state to execute the function?
navIsCollapsed: false,
};
// this controls rendering of huge images
toggleShowImages() {
this.setState({
navIsCollapsed: !this.state.navIsCollapsed,
});
}
// I want this to be executed by width < 1000
handleSideNavToggle = () => {
this.toggleShowImages(); // controls if React renders components
document.body.classList.toggle("side-nav-closed");
}
Here's render the button that's currently executing the function. I want width < 1000 to programmatically execute its function.
// window width < 1000 should execute this function
<div onClick={this.handleSideNavToggle}>Don't render huge images</div>
// here are the images the function conditionally renders
<should show images &&
<div>Massive huge image</div>
<div>Massive huge image</div>
<div>Massive huge image</div>
>
I could use CSS media query to show or hide the massive images I don't want, but that's horrible use of React.
I've looked and tried to implement similar questions on SO that either invoke plugins, are out of date, or the use case is too different (for example, "re-render everything based on screen size"). I've also tried to React-ify vanilla javascript. This seems like it ought to be simple to do but I can't make it work.
Any React wizards out there who can answer with a clean, efficient solution?
Use the above method that Mathis Delaunay mentioned to get viewport/window width, then to get rid of that button. Just simply add a condition to whether render it or not and then watch on state changes to trigger the function.
Here I use hooks to do it
import React, { useEffect, useState } from "react";
import ReactDOM from "react-dom";
function App() {
const [width, setWidth] = useState(window.innerWidth);
useEffect(() => {
function handleResize() {
setWidth(window.innerWidth);
}
window.addEventListener("resize", handleResize);
return () => window.removeEventListener("resize", handleResize);
}, [width]);
useEffect(() => {
width < 600 && handleSideNavToggle();
},[width]);
function handleSideNavToggle() {
console.log("toggle it");
}
return (
<div className="App">
{width > 600 && (
<button onClick={() => handleSideNavToggle()}>
Don't render huge images
</button>
)}
</div>
);
}
const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);
Here is a working example. I set the width to be handled as 600 to make it easy to see.
https://codesandbox.io/s/react-hooks-counter-demo-w9wgv
Try looking at this answer, i think it is what your are searching for :
Get viewport/window height in ReactJS
You just need to check in the updateWindowDimension if the window.innerWidth is under 1000, if so, change the css button property to display : none; or visibility: hidden;.

Get height of tab bar on any device in React-Navigation

I'd like to position a component just above the createBottomTabNavigator TabBar in React-Navigation V2.
The height of the tab bar seems to differ on various devices (iOS devices especially). Is there a way to calculate the height of the tab bar as it is displayed on a device?
As you check the source code for react-navigation-tabs which react-navigation uses for createBottomTabNavigator, you can see that there is only 2 different bottom tab bar heights. Compact and default, which changes between some conditions. You can also set your component's position according to these conditions manually.
React Navigation 5 +
You now have two options to get the height of the bottomTabBar.
To get the height of the bottom tab bar, you can use BottomTabBarHeightContext with React's Context API or useBottomTabBarHeight, which is a custom Hook:
import { BottomTabBarHeightContext } from '#react-navigation/bottom-tabs';
// ...
<BottomTabBarHeightContext.Consumer>
{tabBarHeight => (
/* render something */
)}
</BottomTabBarHeightContext.Consumer>
or
import { useBottomTabBarHeight } from '#react-navigation/bottom-tabs';
// ...
const tabBarHeight = useBottomTabBarHeight();
Make sure you use version 5.11.9 or greater
To avoid Ipnone X issues they use react-native-safe-area-view inside.
You just need to know padding at bottom:
import { getInset } from 'react-native-safe-area-view'
const bottomOffset = getInset('bottom')
It solved problem for us.
We also use specific component position.
Updated according to library update:
import { SafeAreaConsumer } from 'react-native-safe-area-context'
<SafeAreaConsumer>
{insets => (
<TouchableOpacity
style={{
paddingBottom: 11 + insets.bottom,
}}
>
...
</TouchableOpacity>
)}
</SafeAreaConsumer>
or hook:
const insets = useSafeArea();
For your issue of how to position something above the tab bar, you can also achieve this without absolute positioning. This way you aren't relying on how the logic of determining the height of the bar is implemented (which may also change in the future).
import { createBottomTabNavigator, BottomTabBar } from "react-navigation"
createBottomTabNavigator({
// Your tabs
}, {
tabBarComponent: (props) => <BottomTabBar {...props} />
})
For example, if you wanted a little red bar above your tabs, you could do the following
tabBarComponent: (props) => (
<View>
<View style={{ backgroundColor: "red", height: 10 }} />
<BottomTabBar {...props} />
</View>
)
The other answer by benny points to where you need to go, but doesn't give you an easy way to check if . To complete the answer, I'll elaborate on the exact checks required to know which height to use. First we need to know if the tab bar is in adaptive mode or not. If you haven't passed "adaptive" as a parameter, adaptive is set to true for all iOS devices with iOS 11+. If it's not iOS11+, then adaptive is false. So, if you HAVE NOT passed "adaptive" as a parameter to tabBarOptions, the function is:
import {Platform, Dimensions} from 'react-native';
const isLandscape = () => {
const dim = Dimensions.get('screen');
return dim.width >= dim.height;
};
function tabBarHeight() {
const majorVersion = parseInt(Platform.Version, 10);
const isIos = Platform.OS === 'ios';
const isIOS11 = majorVersion >= 11 && isIos;
if(Platform.isPad) return 49;
if(isIOS11 && !isLandscape()) return 49;
return 29;
}

Resources