@2hats/react-native-image-picker 中文文档教程

Question

React Native Image Picker

一个 React Native 模块，允许您使用本机 UI 从设备库或直接从相机中选择照片/视频，如下所示：

iOS	Android

Before you open an issue

这个库开始是本机 iOS 图像选择器的基本桥梁，我想保留它那样。 因此，此处将不支持超出本机 UIImagePickerController 支持的功能。 多图像选择、对裁剪工具的更多控制以及横向支持是原生 iOS 功能中缺少的东西 - 不是我的库的问题。 如果你需要这些东西，react-native-image-crop-picker 可能是更好的选择为你。

Table of contents

• Install
• Usage
• Direct launch
• Options
• Response object

Install

NOTE: THIS PACKAGE IS NOW BUILT FOR REACT NATIVE 0.40 OR GREATER! IF YOU NEED TO SUPPORT REACT NATIVE < 0.40, YOU SHOULD INSTALL THIS PACKAGE @0.24

npm install react-native-image-picker@latest --save

Automatic Installation

react-native link

重要说明：对于 iOS，您仍然需要执行第 4 步和第 2 步， 3、5 for Android 的手册说明如下。

Manual Installation

iOS

1. In the XCode's "Project navigator", right click on your project's Libraries folder ➜ Add Files to <...>
2. Go to node_modules ➜ react-native-image-picker ➜ ios ➜ select RNImagePicker.xcodeproj
3. Add RNImagePicker.a to Build Phases -> Link Binary With Libraries
4. For iOS 10+, Add the NSPhotoLibraryUsageDescription, NSCameraUsageDescription, and NSMicrophoneUsageDescription (if allowing video) keys to your Info.plist with strings describing why your app needs these permissions. Note: You will get a SIGABRT crash if you don't complete this step
5. Compile and have fun

Android

1. 将以下行添加到 android/settings.gradle：

   include ':react-native-image-picker'
   project(':react-native-image-picker').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-image-picker/android')
   

2. 在 android/build.gradle 中将 android 构建工具版本更新为 2.2.+：

   buildscript {
       ...
       dependencies {
           classpath 'com.android.tools.build:gradle:2.2.+' // <- USE 2.2.+ version
       }
       ...
   }
   ...
   

3. 更新android/gradle/wrapper/gradle-wrapper.properties 中的 gradle 版本为 2.14.1：

   ...
   distributionUrl=https\://services.gradle.org/distributions/gradle-2.14.1-all.zip
   

4. 将编译行添加到 android/app/build 中的依赖 项.gradle：

   dependencies {
       compile project(':react-native-image-picker')
   }
   

5. 在AndroidManifest.xml中添加需要的权限：

   <uses-permission android:name="android.permission.CAMERA" />
   <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
   

6. 在MainApplication.java中添加导入和链接包：

   import com.imagepicker.ImagePickerPackage; // <-- add this import
   
   public class MainApplication extends Application implements ReactApplication {
       @Override
       protected List<ReactPackage> getPackages() {
           return Arrays.<ReactPackage>asList(
               new MainReactPackage(),
               new ImagePickerPackage() // <-- add this line
               // OR if you want to customize dialog style
               new ImagePickerPackage(R.style.my_dialog_style)
           );
       }
   }
   

Android (Optional)

对话框的自定义设置android /app/res/values/themes.xml：

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <style name="DefaultExplainingPermissionsTheme" parent="Theme.AppCompat.Light.Dialog.Alert">
        <!-- Used for the buttons -->
        <item name="colorAccent">@color/your_color</item>

        <!-- Used for the title and text -->
        <item name="android:textColorPrimary">@color/your_color</item>

        <!-- Used for the background -->
        <item name="android:background">@color/your_color</item>
    </style>
<resources>

如果 MainActivity 不是 ReactActivity 的实例，则需要实现 OnImagePickerPermissionsCallback to MainActivity：

import com.imagepicker.permissions.OnImagePickerPermissionsCallback; // <- add this import
import com.facebook.react.modules.core.PermissionListener; // <- add this import

public class MainActivity extends YourActivity implements OnImagePickerPermissionsCallback {
  private PermissionListener listener; // <- add this attribute

  // Your methods here

  // Copy from here

  @Override
  public void setPermissionListener(PermissionListener listener)
  {
    this.listener = listener;
  }

  @Override
  public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults)
  {
    if (listener != null)
    {
      listener.onRequestPermissionsResult(requestCode, permissions, grantResults);
    }
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
  }

  // To here
}

此代码允许将请求权限的结果传递给本机部分。

Usage

var ImagePicker = require('react-native-image-picker');

// More info on all the options is below in the README...just some common use cases shown here
var options = {
  title: 'Select Avatar',
  customButtons: [
    {name: 'fb', title: 'Choose Photo from Facebook'},
  ],
  storageOptions: {
    skipBackup: true,
    path: 'images'
  }
};

/**
 * The first arg is the options object for customization (it can also be null or omitted for default options),
 * The second arg is the callback which sends object: response (more info below in README)
 */
ImagePicker.showImagePicker(options, (response) => {
  console.log('Response = ', response);

  if (response.didCancel) {
    console.log('User cancelled image picker');
  }
  else if (response.error) {
    console.log('ImagePicker Error: ', response.error);
  }
  else if (response.customButton) {
    console.log('User tapped custom button: ', response.customButton);
  }
  else {
    let source = { uri: response.uri };

    // You can also display the image using data:
    // let source = { uri: 'data:image/jpeg;base64,' + response.data };

    this.setState({
      avatarSource: source
    });
  }
});

稍后，如果您想在 render() 方法中显示此图像：

<Image source={this.state.avatarSource} style={styles.uploadAvatar} />

Directly Launching the Camera or Image Library

要直接启动相机或图像库（跳过警报对话框），您可以 执行以下操作：

// Launch Camera:
ImagePicker.launchCamera(options, (response)  => {
  // Same code as in above section!
});

// Open Image Library:
ImagePicker.launchImageLibrary(options, (response)  => {
  // Same code as in above section!
});

Note

在 iOS 上，不要假设返回的绝对 uri 会持续存在。 参见#107

Options

option	iOS	Android	Info
title	OK	OK	Specify null or empty string to remove the title
cancelButtonTitle	OK	OK	Specify null or empty string to remove this button (Android only)
takePhotoButtonTitle	OK	OK	Specify null or empty string to remove this button
chooseFromLibraryButtonTitle	OK	OK	Specify null or empty string to remove this button
customButtons	OK	OK	An array containing objects with the name and title of buttons
cameraType	OK	-	'front' or 'back'
mediaType	OK	OK	'photo', 'video', or 'mixed' on iOS, 'photo' or 'video' on Android
maxWidth	OK	OK	Photos only
maxHeight	OK	OK	Photos only
quality	OK	OK	0 to 1, photos only
videoQuality	OK	OK	'low', 'medium', or 'high' on iOS, 'low' or 'high' on Android
durationLimit	OK	OK	Max video recording time, in seconds
rotation	-	OK	Photos only, 0 to 360 degrees of rotation
allowsEditing	OK	-	bool - enables built in iOS functionality to resize the image after selection
noData	OK	OK	If true, disables the base64 data field from being generated (greatly improves performance on large photos)
storageOptions	OK	OK	If this key is provided, the image will be saved in your app's Documents directory on iOS, or your app's Pictures directory on Android (rather than a temporary directory)
storageOptions.skipBackup	OK	-	If true, the photo will NOT be backed up to iCloud
storageOptions.path	OK	-	If set, will save the image at Documents/[path]/ rather than the root Documents
storageOptions.cameraRoll	OK	OK	If true, the cropped photo will be saved to the iOS Camera Roll or Android DCIM folder.
storageOptions.waitUntilSaved	OK	-	If true, will delay the response callback until after the photo/video was saved to the Camera Roll. If the photo or video was just taken, then the file name and timestamp fields are only provided in the response object when this is true.
permissionDenied.title	-	OK	Title of explaining permissions dialog. By default Permission denied.
permissionDenied.text	-	OK	Message of explaining permissions dialog. By default To be able to take pictures with your camera and choose images from your library..
permissionDenied.reTryTitle	-	OK	Title of re-try button. By default re-try
permissionDenied.okTitle	-	OK	Title of ok button. By default I'm sure

The Response Object

key	iOS	Android	Description
didCancel	OK	OK	Informs you if the user cancelled the process
error	OK	OK	Contains an error message, if there is one
customButton	OK	OK	If the user tapped one of your custom buttons, contains the name of it
data	OK	OK	The base64 encoded image data (photos only)
uri	OK	OK	The uri to the local file asset on the device (photo or video)
origURL	OK	-	The URL of the original asset in photo library, if it exists
isVertical	OK	OK	Will be true if the image is vertically oriented
width	OK	OK	Image dimensions
height	OK	OK	Image dimensions
fileSize	OK	OK	The file size (photos only)
type	-	OK	The file type (photos only)
fileName	OK (photos and videos)	OK (photos)	The file name
path	-	OK	The file path
latitude	OK	OK	Latitude metadata, if available
longitude	OK	OK	Longitude metadata, if available
timestamp	OK	OK	Timestamp metadata, if available, in ISO8601 UTC format
originalRotation	-	OK	Rotation degrees (photos only) See #109