I'm building an app with react-navigation-4.2.1. The app has multiple stack navigators. So there are a lots of navigation.push('Routename') calls.
Trouble is when the control surface (i.e. TouchableOpacity) is tapped rapidly multiple times (first one, and the rest during screen transition) I end up pushing multiple screens into the stack. Is there a way to restrict the surface to the first tap/call of push()?
The component below is what i use to make things touchable. it handle multiple touches in small period of time.
Use component below instead of TouchableOpacity. wrap any thing you want with this component and it will be touchable.
<SafeTouch
onPress={...}
>
<Text> hey! im a touchable text now</Text>
</SafeTouch>
The component below is written used TypeScirpt.
every touch within 300ms after first touch will be ignored(thats where help you with your problem).
import * as React from 'react'
import { TouchableOpacity } from 'react-native'
interface ISafeTouchProps {
onPress: () => void
onLongPress?: () => void
onPressIn?: () => void
onPressOut?: () => void,
activeOpacity?: number,
disabled?: boolean,
style: any
}
export class SafeTouch extends React.PureComponent<ISafeTouchProps> {
public static defaultProps: ISafeTouchProps = {
onPress: () => { },
onLongPress: () => { },
onPressIn: () => { },
onPressOut: () => { },
disabled: false,
style: null
}
private isTouchValid: boolean = true
private touchTimeout: any = null
public constructor(props: ISafeTouchProps) {
super(props)
{// Binding methods
this.onPressEvent = this.onPressEvent.bind(this)
}
}
public render(): JSX.Element {
return (
<TouchableOpacity
onPress={this.onPressEvent}
onLongPress={this.props.onLongPress}
onPressIn={this.props.onPressIn}
onPressOut={this.props.onPressOut}
activeOpacity={this.props.activeOpacity}
disabled={this.props.disabled}
style={[{minWidth: 24, minHeight: 24}, this.props.style]}
>
{
this.props.children
}
</TouchableOpacity>
)
}
public componentWillUnmount() {
this.clearTimeoutIfExists()
}
private onPressEvent(): void {
requestAnimationFrame(() => {
if (this.isTouchValid === false) {
return
}
this.isTouchValid = false
this.clearTimeoutIfExists()
this.touchTimeout = setTimeout(() => {
this.isTouchValid = true
}, 300)
if (typeof this.props.onPress === 'function') {
this.props.onPress()
}
})
}
private clearTimeoutIfExists(): void {
if (this.touchTimeout != null) {
clearTimeout(this.touchTimeout)
this.touchTimeout = null
}
}
}
This is the proper behavior for Push and it is not a bug if you want
to avoid the duplicate screen on double tab you can just use navigation.navigate.
To avoid pushing the screen more than once when clicking in the same button in a short span of time, I created a generic hook to avoid running a function more than once (accepting an interval to allow run again):
export const useCallOnce = <T extends unknown[], K>(
fn: (...args: T) => K,
allowAfter?: number,
) => {
const ref = React.useRef<number | undefined>();
const resultFn = (...args: T) => {
const now = new Date().getTime();
if (!ref.current || (allowAfter && ref.current + allowAfter < now)) {
ref.current = now;
return fn(...args);
}
};
return resultFn;
};
Then, you can just call it as in the following example:
const navigation = useNavigation<NativeStackNavigationProp<{ ExampleScreen: undefined }>>();
const push = useCallOnce(() => navigation.push('ExampleScreen'), 500);
// just call on the button click event as: onSomeEvent={() => push()}
You can create a generic button component that accept the push parameters with the hook above, similar to the example, and use this button whenever you want a button to navigate between pages.
Related
I have the simplest example possible with useDerivedValue:
A SharedValue that is modified when scrolling.
A derived boolean value based on this scroll position
const isShown = useDerivedValue(() => {
console.log('y', currentPositionY.value);
return currentPositionY.value > 40;
}, [currentPositionY]);
The y is logged and modified as it should.
A component that should display a different text based on this boolean:
const TestC = ({ isShown }: { isShown: SharedValue<boolean> }) => {
console.log('isS', isShown.value);
if (isShown.value) {
return <Text>shown</Text>;
} else {
return <Text>not shown</Text>;
}
};
But the TestC component is not updated following the derived value.
What am I missing?
I have a custom plugin in ckeditor5.
When user click on toolbar icon my plugin convert selected test to custom element with a custom attribute name comment-id.
this work properly.
Now I want to watch on click element and get comment-id on click and I don't know how can I do that.
this is the code of my custom plugin
import uploadIcon from './message.svg'
import ButtonView from '#ckeditor/ckeditor5-ui/src/button/buttonview'
import Plugin from '#ckeditor/ckeditor5-core/src/plugin'
import Command from '#ckeditor/ckeditor5-core/src/command'
import './comment.css'
export default class CustomFileExporerPlugin extends Plugin {
init() {
const editor = this.editor
const config = editor.config.get('comment')
console.log(editor.editing.view.document.isFocused)
editor.editing.view.document.on('click', a => {
console.log(a)
})
editor.model.schema.extend('$text', { allowAttributes: 'comment' })
editor.conversion.attributeToElement({
model: 'comment',
view: (commentId, writer) => {
debugger
if (writer) {
return writer.writer.createAttributeElement(
'comment',
{
'comment-id': commentId,
class: `ck-comment-marker`
},
{ priority: 5 }
)
}
}
})
editor.commands.add('comment', new CommentCommand(editor))
editor.ui.componentFactory.add('comment', locale => {
const view = new ButtonView(locale)
view.set({
label: 'add comment',
icon: uploadIcon,
tooltip: true
})
view.on('execute', async () => {
editor.editing.view.focus()
let id = await config.callback()
editor.execute('comment', { value: 'comment', id })
})
return view
})
}
}
class CommentCommand extends Command {
refresh() {
const model = this.editor.model
const doc = model.document
this.value = doc.selection.getAttribute('comment')
this.isEnabled = model.schema.checkAttributeInSelection(
doc.selection,
'comment'
)
}
execute(options = {}) {
const model = this.editor.model
const document = model.document
const selection = document.selection
const highlighter = options.value
model.change(writer => {
const ranges = model.schema.getValidRanges(
selection.getRanges(),
'comment'
)
if (selection.isCollapsed) {
const position = selection.getFirstPosition()
if (selection.hasAttribute('comment')) {
const isSameHighlight = value => {
return (
value.item.hasAttribute('comment') &&
value.item.getAttribute('comment') === this.value
)
}
const highlightStart = position.getLastMatchingPosition(
isSameHighlight,
{ direction: 'backward' }
)
const highlightEnd = position.getLastMatchingPosition(isSameHighlight)
const highlightRange = writer.createRange(
highlightStart,
highlightEnd
)
writer.removeAttribute('comment', highlightRange)
writer.removeSelectionAttribute('comment')
} else if (highlighter) {
writer.setSelectionAttribute('comment', highlighter)
}
} else {
for (const range of ranges) {
writer.setAttribute('comment', options, range)
}
}
})
}
}
When rendering editor, you can catch custom plugin click event using below code.
const command = editor.commands.get('comment')
command.on('execute', () => { catch click event in custom plugin})
I need to perform different action on single and double tap on a view. On double tap I need to like the image just like Instagram double tap experience. On single tap I need to open a modal.
For double tap I have used TapGestureHandler which works perfect
<TapGestureHandler
ref={this.doubleTapRef}
maxDelayMs={200}
onHandlerStateChange={this.onProductImageDoubleTap}
numberOfTaps={2}
>
<SomeChildComponent ...
But when I add any Touchable to detect single tap in the
<TouchableWithoutFeedback onPress={this.imageTapped}>
on double tapping the this.imageTapped function is called twice along with this.onProductImageDoubleTap. Is there any way to cancel tap on touchable when two taps are done is quick succession
The best solution is not using state, since setting state is asynchronous.Works like a charm for me on android !
let lastPress = 0;
const functionalComp = () => {
const onDoublePress = () => {
const time = new Date().getTime();
const delta = time - lastPress;
const DOUBLE_PRESS_DELAY = 400;
if (delta < DOUBLE_PRESS_DELAY) {
// Success double press
console.log('double press');
}
lastPress = time;
};
return <View
onStartShouldSetResponder =
{(evt) => onDoublePress()}>
</View>
}
2022 update
This is a performant native solution without any JS thread blocking calculation!
Many more tips here
const tap = Gesture.Tap()
.numberOfTaps(2)
.onStart(() => {
console.log('Yay, double tap!');
});
return (
<GestureDetector gesture={tap}>
{children}
</GestureDetector>
);
The best solution is use react-native-gesture-handler
https://github.com/software-mansion/react-native-gesture-handler
Here is my solution -
import {State, TapGestureHandler} from 'react-native-gesture-handler';
export const DoubleTap = ({children}: any) => {
const doubleTapRef = useRef(null);
const onSingleTapEvent = (event: any) => {
if (event.nativeEvent.state === State.ACTIVE) {
console.log("single tap 1");
}
};
const onDoubleTapEvent = (event: any) => {
if (event.nativeEvent.state === State.ACTIVE) {
console.log("double tap 1");
}
};
return (
<TapGestureHandler
onHandlerStateChange={onSingleTapEvent}
waitFor={doubleTapRef}>
<TapGestureHandler
ref={doubleTapRef}
onHandlerStateChange={onDoubleTapEvent}
numberOfTaps={2}>
{children}
</TapGestureHandler>
</TapGestureHandler>
);
};
Now we will wrap the component where we need to detect the double and single tap : -
<DoubleTap>
<View>
...some view and text
</View>
</DoubleTap>
The package react-native-double-tap seems to be what you are looking for.
since you are asking on handling one tap and double tap, here's a simple code i think should covered your issue
Untested
first defined clickCount:0 in state:
state={clickCount:0, //another state}
then create a function with setTimeout to handling if user tapping once or two times:
handlingTap(){
this.state.clickCount==1 ?
//user tap twice so run this.onProductImageDoubleTap()
this.onProductImageDoubleTap :
//user tap once so run this.imageTapped with setTimeout and setState
//i set 1 sec for double tap, so if user tap twice more than 1 sec, it's count as one tap
this.setState({clickCount:1}, ()=>{
setTimeout(()=>{
this.setState({clickCount:0})
this.imageTapped()
}, 1000)
})
}
<TouchableWithoutFeedback onPress={this.handlingTap()}/>
just used TouchableWithoutFeedback instead of TapGestureHandler
With hooks:
const [lastPressed, setLastPressed] = useState(0);
const handlePress = useCallback(() => {
const time = new Date().getTime();
const delta = time - lastPressed;
setLastPressed(time);
if (lastPressed) {
if (delta < DOUBLE_PRESS_DELAY) {
console.log('double press');
} else {
console.log('single press');
}
}
}, [lastPressed]);
I have modified flix's answer into this. By this way, you can catch one and double click separately. I also changed debounce into 300ms which is fairly well for one and double click.
state={clickCount:0, //another state}
Binding context into the handlingTap method
constructor(props){
super(props)
this.handlingTap = this.handlingTap.bind(this)
}
With this function you can catch them separately
handlingTap() {
this.state.clickCount === 1
? this.doubleClick() // This catches double click
: this.setState(state => ({ clickCount: state.clickCount + 1 }), () => {
setTimeout(() => {
if (this.state.clickCount !== 2) {
this.oneClick() // this catches one click
}
this.setState({ clickCount: 0 })
}, 300)
})
}
In the button you can use this way
<TouchableWithoutFeedback onPress={this.handlingTap}></TouchableWithoutFeedback>
I need some buttons that can be pressed at the same time, but currently if you press one, it 'claims' responsiveness and the others can't be pressed anymore. How do I do this?
Got it. You have to use ReactNativeEventEmitter to directly listen to touch events and bypass the Gesture Responder stuff entirely. Below is a decorator class that calls onTouchStart, onTouchEnd and onTouchMove in the wrapped class whenever those touch events are received.
'use strict';
import React, {Component} from 'react-native';
import ReactNativeEventEmitter from 'ReactNativeEventEmitter';
import NodeHandle from 'NodeHandle';
export const multitouchable = BaseComponent => {
return class extends Component {
constructor(props, context) {
super(props, context);
this.comp = null;
this.compId = null;
}
componentDidMount() {
if(this.comp && this.compId){
this.comp.onTouchStart && ReactNativeEventEmitter.putListener(this.compId, 'onTouchStart', e => this.comp.onTouchStart(e));
this.comp.onTouchEnd && ReactNativeEventEmitter.putListener(this.compId, 'onTouchEnd', e => this.comp.onTouchEnd(e));
this.comp.onTouchMove && ReactNativeEventEmitter.putListener(this.compId, 'onTouchMove', e => this.comp.onTouchMove(e));
}
}
componentWillUnmount() {
if(this.comp && this.compId){
this.comp.onTouchStart && ReactNativeEventEmitter.deleteListener(this.compId, 'onTouchStart');
this.comp.onTouchEnd && ReactNativeEventEmitter.deleteListener(this.compId, 'onTouchEnd');
this.comp.onTouchMove && ReactNativeEventEmitter.deleteListener(this.compId, 'onTouchMove');
}
}
render() {
return (
<BaseComponent {...this.props} {...this.state}
ref={c => {
this.comp = c;
const handle = React.findNodeHandle(c);
if(handle)
this.compId = NodeHandle.getRootNodeID(handle);
}}
/>
);
}
};
}
just trying come silly stuff and playing around with Cycle.js. and running into problem. Basically I just have a button. When you click it it's suppose to navigate the location to a random hash and display it. Almost like a stupid router w/o predefined routes. Ie. routes are dynamic. Again this isn't anything practical I am just messing with some stuff and trying to learn Cycle.js. But the code below crashes after I click "Add" button. However the location is updated. If I actually just navigate to "#/asdf" it displays the correct content with "Hash: #/asdf". Not sure why the flow is crashing with error:
render-dom.js:242 TypeError: Cannot read property 'subscribe' of undefined(…)
import Rx from 'rx';
import Cycle from '#cycle/core';
import { div, p, button, makeDOMDriver } from '#cycle/dom';
import { createHashHistory } from 'history';
import ranomdstring from 'randomstring';
const history = createHashHistory({ queryKey: false });
function CreateButton({ DOM }) {
const create$ = DOM.select('.create-button').events('click')
.map(() => {
return ranomdstring.generate(10);
}).startWith(null);
const vtree$ = create$.map(rs => rs ?
history.push(`/${rs}`) :
button('.create-button .btn .btn-default', 'Add')
);
return { DOM: vtree$ };
}
function main(sources) {
const hash = location.hash;
const DOM = sources.DOM;
const vtree$ = hash ?
Rx.Observable.of(
div([
p(`Hash: ${hash}`)
])
) :
CreateButton({ DOM }).DOM;
return {
DOM: vtree$
};
}
Cycle.run(main, {
DOM: makeDOMDriver('#main-container')
});
Thank you for the help
I would further suggest using #cycle/history to do your route changing
(Only showing relevant parts)
import {makeHistoryDriver} from '#cycle/history'
import {createHashHistory} from 'history'
function main(sources) {
...
return {history: Rx.Observable.just('/some/route') } // a stream of urls
}
const history = createHashHistory({ queryKey: false })
Cycle.run(main, {
DOM: makeDOMDriver('#main-container'),
history: makeHistoryDriver(history),
})
On your function CreateButton you are mapping your clicks to history.push() instead of mapping it to a vtree which causes the error:
function CreateButton({ DOM }) {
...
const vtree$ = create$.map(rs => rs
? history.push(`/${rs}`) // <-- not a vtree
: button('.create-button .btn .btn-default', 'Add')
);
...
}
Instead you could use the do operator to perform the hashchange:
function CreateButton({ DOM }) {
const create$ =
...
.do(history.push(`/${rs}`)); // <-- here
const vtree$ = Observable.of(
button('.create-button .btn .btn-default', 'Add')
);
...
}
However in functional programming you should not perform side effects on you app logic, every function must remain pure. Instead, all side effects should be handled by drivers. To learn more take a look at the drivers section on Cycle's documentation
To see a working driver jump at the end of the message.
Moreover on your main function you were not using streams to render your vtree. It would have not been reactive to locationHash changes because vtree$ = hash ? ... : ... is only evaluated once on app bootstrapping (when the main function is evaluated and "wires" every streams together).
An improvement will be to declare your main's vtree$ as following while keeping the same logic:
const vtree$ = hash$.map((hash) => hash ? ... : ...)
Here is a complete solution with a small locationHash driver:
import Rx from 'rx';
import Cycle from '#cycle/core';
import { div, p, button, makeDOMDriver } from '#cycle/dom';
import { createHashHistory } from 'history';
import randomstring from 'randomstring';
function makeLocationHashDriver (params) {
const history = createHashHistory(params);
return (routeChange$) => {
routeChange$
.filter(hash => {
const currentHash = location.hash.replace(/^#?\//g, '')
return hash && hash !== currentHash
})
.subscribe(hash => history.push(`/${hash}`));
return Rx.Observable.fromEvent(window, 'hashchange')
.startWith({})
.map(_ => location.hash);
}
}
function CreateButton({ DOM }) {
const create$ = DOM.select('.create-button').events('click')
.map(() => randomstring.generate(10))
.startWith(null);
const vtree$ = Rx.Observable.of(
button('.create-button .btn .btn-default', 'Add')
);
return { DOM: vtree$, routeChange$: create$ };
}
function main({ DOM, hash }) {
const button = CreateButton({ DOM })
const vtree$ = hash.map(hash => hash
? Rx.Observable.of(
div([
p(`Hash: ${hash}`)
])
)
: button.DOM
)
return {
DOM: vtree$,
hash: button.routeChange$
};
}
Cycle.run(main, {
DOM: makeDOMDriver('#main-container'),
hash: makeLocationHashDriver({ queryKey: false })
});
PS: there is a typo in your randomstring function name, I fixed it in my example.