npm package: @knezevicdev/react-native-image-zoom-viewer
Description: react native image viewer,大图浏览
Author: knezevicdev
Latest version: 1.0.3

## Show Cases

**Swiper image**

![](https://cloud.githubusercontent.com/assets/7970947/21086300/388dedfc-c056-11e6-955e-0a2a0b541f7f.gif)

**Zoom while sliding**

![](https://cloud.githubusercontent.com/assets/7970947/21086323/7355face-c056-11e6-8d68-384000d41d47.gif)

**Swipe down**

![](https://user-images.githubusercontent.com/7970947/37651584-8b642458-2c73-11e8-9ecc-ef7c72aca1be.gif)

## Getting Started

### Installation

```bash
npm i react-native-image-zoom-viewer --save
```

### Basic Usage

- Install create-react-native-app first

```bash
$ npm install -g create-react-native-app
```

- Initialization of a react-native project

```bash
$ create-react-native-app AwesomeProject
```

- Then, edit `AwesomeProject/App.js`, like this:

```typescript
import { Modal } from 'react-native';
import ImageViewer from 'react-native-image-zoom-viewer';

const images = [{
    // Simplest usage.
    url: 'https://avatars2.githubusercontent.com/u/7970947?v=3&s=460',

    // width: number
    // height: number
    // Optional, if you know the image size, you can set the optimization performance

    // You can pass props to <Image />.
    props: {
        // headers: ...
    }
}, {
    url: '',
    props: {
        // Or you can set source directory.
        source: require('../background.png')
    }
}]

export default class App extends React.Component {
    render: function() {
        return (
            <Modal visible={true} transparent={true}>
                <ImageViewer imageUrls={images}/>
            </Modal>
        )
    }
}
```

### Props

| parameter              | type                                                                                   | required | description                                                                                                                                                                                                                          | default                                                   |
| :--------------------- | :------------------------------------------------------------------------------------- | :------- | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | :-------------------------------------------------------- |
| imageUrls              | array                                                                                  | yes      | Image Source                                                                                                                                                                                                                         |                                                           |
| enableImageZoom        | boolean                                                                                | no       | Enable image zoom                                                                                                                                                                                                                    | `true`                                                    |
| onShowModal            | function<br><br>`(content?: JSX.Element) => void`                                      | no       | The callback for show modal                                                                                                                                                                                                          | `() => {}`                                                |
| onCancel               | function<br><br>`() => void`                                                           | no       | The callback for cancel modal                                                                                                                                                                                                        | `() => {}`                                                |
| flipThreshold          | number                                                                                 | no       | Swipe threshold of the next page                                                                                                                                                                                                     | `80`                                                      |
| maxOverflow            | number                                                                                 | no       | The X position maximum, that current page can slide to the next page                                                                                                                                                                 | `300`                                                     |
| index                  | number                                                                                 | no       | Init index of images                                                                                                                                                                                                                 | `0`                                                       |
| failImageSource        | string, object<br><br>`{url: string}`                                                  | no       | placeholder for fail                                                                                                                                                                                                                 | `''`                                                      |
| loadingRender          | function<br><br>`() => React.ReactElement<any>`                                        | no       | placeholder for loading                                                                                                                                                                                                              | `() => null`                                              |
| onSaveToCamera         | function<br><br>`(index?: number => void`                                              | no       | The callback for save to camera                                                                                                                                                                                                      | `() => {}`                                                |
| onChange               | function<br><br>`(index?: number => void`                                              | no       | When the image changed                                                                                                                                                                                                               | `() => {}`                                                |
| onMove                 | ( position: [IOnMove](https://github.com/ascoders/react-native-image-zoom/blob/master/src/image-zoom/image-zoom.type.ts) )=>void | reports movement position data (helpful to build overlays)                                                                                                            | ()=> {}      |
| saveToLocalByLongPress | boolean                                                                                | no       | Enable save to camera when long press                                                                                                                                                                                                | `true`                                                    |
| onClick                | function<br><br>`(onCancel?: function) => void`                                        | no       | Onclick                                                                                                                                                                                                                              | `(onCancel) => {onCancel()}`                              |
| onDoubleClick          | function<br><br>`(onCancel?: function) => void`                                        | no       | OnDoubleClick                                                                                                                                                                                                                        | `(onCancel) => {onCancel()}`                              |
| onSave                 | function<br><br>`(url: string) => void`                                                | no       | The picture is saved to the local method, if you write this method will not call the system default method for Android does not support saveToCameraRoll remote picture, you can call this callback in Android call native interface |                                                           |
| renderHeader           | function<br><br>`(currentIndex?: number) => React.ReactElement<any>`                   | no       | Custom header                                                                                                                                                                                                                        | `() => null`                                              |
| renderFooter           | function<br><br>`(currentIndex?: number) => React.ReactElement<any>`                   | no       | Custom footer                                                                                                                                                                                                                        | `() => null`                                              |
| renderIndicator        | function<br><br>`(currentIndex?: number, allSize?) => React.ReactElement<any>`: number | no       | Custom indicator                                                                                                                                                                                                                     | `(currentIndex, allSize) => currentIndex + "/" + allSize` |
| renderImage            | function<br><br>`(props: any) => React.ReactElement<any>`                              | no       | Custom image component                                                                                                                                                                                                               | `(props) => <Image {...props} />`                         |
| renderArrowLeft        | function<br><br>`() => React.ReactElement<any>`                                        | no       | Custom left arrow                                                                                                                                                                                                                    | `() => null`                                              |
| renderArrowRight       | function<br><br>`() => React.ReactElement<any>`                                        | no       | Custom right arrow                                                                                                                                                                                                                   | `() => null`                                              |
| onSwipeDown            | function<br><br>`() => void`                                                           | no       | Callback for swipe down                                                                                                                                                                                                              | `() => null`                                              |
| footerContainerStyle   | object<br><br>`{someStyle: someValue}`                                                 | no       | custom style props for container that will be holding your footer that you pass                                                                                                                                                      | `bottom: 0, position: "absolute", zIndex: 9999`           |
| backgroundColor        | string<br><br>`white`                                                                  | no       | Component background color                                                                                                                                                                                                           | `black`                                                   |
| enableSwipeDown        | boolean                                                                                | no       | Enable swipe down to close image viewer. When swipe down, will trigger onCancel.                                                                                                                                                     | `false`                                                   |
| swipeDownThreshold     | number                                                                                 | no       | Threshold for firing swipe down function                                                                                                                                                                                             |                                                           |
| doubleClickInterval    | number                                                                                 | no       | Double click interval.                                                                                                                                                                                                               |                                                           |
| pageAnimateTime        | number                                                                                 | no       | Set the animation time for page flipping.                                                                                                                                                                                            | `100`                                                     |
| enablePreload          | boolean                                                                                | no       | Preload the next image                                                                                                                                                                                                               | `false`                                                   |
| menus                  | function<br><br>`({cancel,saveToLocal}) => React.ReactElement<any>`                    | no       | Custom menus, with 2 methods:`cancel` to hide menus and `saveToLocal` to save image to camera
| menuContext            | object<br><br>`{someKey: someValue}`                                                   | no       | Custom menu context.                              | `{ saveToLocal: 'save to the album', cancel: 'cancel' }`
## Development pattern

### Step 1, run TS listener

After clone this repo, then:

```bash
npm install
npm start
```

### Step 2, run demo

```bash
cd demo
npm install
npm start
```

Then, scan the QR, use your [expo app](https://expo.io./).

### Dependence

Depend on `react-native-image-pan-zoom`: https://github.com/ascoders/react-native-image-zoom