@nativescript-community/gesturehandler

Declarative API exposing platform native touch and gesture system to NativeScript.

[](#table-of-contents)

Table of Contents

* Installation
* API
* TypeScript
* GestureRootView
* Overriding Nativescript gestures
* Credits
* Examples:
* Demos and Development
* Repo Setup
* Build
* Demos
* Contributing
* Update repo
* Update readme
* Update doc
* Publish
* modifying submodules
* Questions

[](#installation)

Installation

Run the following command from the root of your project:

ns plugin add @nativescript-community/gesturehandler

[](#api)

API

We need to do some wiring when your app starts, so open app.ts and add this before creating any View/App/Frame:

##### TypeScript

``ts
import { install } from '@nativescript-community/gesturehandler';
install();
`

You create a gesture handler using something like this:

`typescript
import { GestureHandlerTouchEvent, GestureHandlerStateEvent, GestureStateEventData, GestureTouchEventData, HandlerType, Manager } from '@nativescript-community/gesturehandler';

function onGestureTouch(args: GestureTouchEventData) {
const { state, extraData, view } = args.data;
view.translateX = extraData.translationX;
view.translateY = extraData.translationY;
}
function onGestureState(args: GestureStateEventData) {
const { state, prevState, extraData, view } = args.data;
console.log('onGestureState', state, prevState, view, extraData);
}
const manager = Manager.getInstance();
const gestureHandler = manager.createGestureHandler(HandlerType.PAN, 10, {
shouldCancelWhenOutside: false
});
gestureHandler.on(GestureHandlerTouchEvent, onGestureTouch, this);
gestureHandler.on(GestureHandlerStateEvent, onGestureState, this);
gestureHandler.attachToView(view);
`

Right now you must not forget to store the gestureHandler somewhere or the gesture won't work on iOS (native object being released). This will be fixed in future versions.

Now about the API. All the gestures for the react counterpart exist with the same options and the same event extraData.


[](#gesturerootview)



GestureRootView

For the gestures to work correctly we need a root view which knows how to handle the gestures.
If using Page (thus Frame) you don't need to do anything.
In case you don't (drawer root view, modals, ...) then you can wrap your views in a GestureRootView which inherits GridLayout


[](#overriding-nativescript-gestures)



Overriding Nativescript gestures

This plugin can also override N gestures completely. This would give much more control over gestures and especially would allow to correctly handle simultaneous gestures likes tap and longpress.

To do that


[](#credits)



Credits

This is a port of react-native-gesturehandler.
The source is based on the source code by Krzysztof Magiera. Don't hesitate to go and thank him for his work!

$3

- Basic
- A basic example showing that overriding N gestures works, even in modals


[](#demos-and-development)



Demos and Development




$3

The repo uses submodules. If you did not clone with --recursive then you need to call
`
git submodule update --init
`

The package manager used to install and link dependencies must be pnpm or yarn. npm wont work.

To develop and test:
if you use yarn then run yarn
if you use pnpm then run pnpm i

Interactive Menu:

To start the interactive menu, run npm start (or yarn start or pnpm start). This will list all of the commonly used scripts.

$3

`bash
npm run build.all
`
WARNING: it seems yarn build.all wont always work (not finding binaries in node_modules/.bin) which is why the doc explicitly uses npm run

$3

`bash
npm run demo.[ng|react|svelte|vue].[ios|android]

npm run demo.svelte.ios # Example
`

Demo setup is a bit special in the sense that if you want to modify/add demos you dont work directly in demo-[ng|react|svelte|vue]
Instead you work in demo-snippets/[ng|react|svelte|vue]
You can start from the install.ts of each flavor to see how to register new demos


[](#contributing)



Contributing

$3

You can update the repo files quite easily

First update the submodules

`bash
npm run update
`

Then commit the changes
Then update common files

`bash
npm run sync
`
Then you can run yarn|pnpm, commit changed files if any

$3


`bash
npm run readme
`

$3

`bash
npm run doc
`

$3

The publishing is completely handled by lerna (you can add -- --bump major to force a major release)
Simply run
`shell
npm run publish
`

$3

The repo uses https:// for submodules which means you won't be able to push directly into the submodules.
One easy solution is t modify ~/.gitconfig and add
`
[url "ssh://git@github.com/"]
pushInsteadOf = https://github.com/
``

[](#questions)

Questions

If you have any questions/issues/comments please feel free to create an issue or start a conversation in the NativeScript Community Discord.