How to achieve image cropping effect in uniapp

How to achieve image cropping effect in uniapp

In today's social media and e-commerce platforms, image cropping has become a common requirement. In uniapp, we can use third-party plug-ins to easily implement image cropping. This article will introduce how to use plug-ins to achieve image cropping effects in uniapp, and provide code examples.

1. Preparation

Before using the plug-in, we need to ensure that the uniapp project has been created and the uni-app plug-in has been installed in the project.

1. Use the command line tool, enter the project root directory, enter the following command to install the uni-app plug-in:

npm install uni-app --save

2. Find pages.json## in the project root directory #File, find the "pages" node, and add a new page under this node for display and operation of image cropping. An example is as follows:

{
  "pages": [
    "pages/index/index",
    "pages/crop/crop"  // 新增的裁剪页面
  ]
}

3. Next, we need to add a button to jump to the cropping page in the

index page. Find the index.vue file and add a click event in the d477f9ce7bf77f53fbcf36bec1b69b7a tag. The example is as follows:

<template>
  <view>
    <button @click="toCrop">图片裁剪</button>
  </view>
</template>

<script>
export default {
  methods: {
    toCrop() {
      uni.navigateTo({
        url: '/pages/crop/crop'
      });
    }
  }
}
</script>

<style></style>

2. Plug-in installation

In uniapp, we can use the

uView plug-in to realize the image cropping function. Next, we need to install and configure the plugin.

1. Use the command line tool, enter the project root directory, enter the following command to install the

uView plug-in:

npm install uview-ui --save

2. In

pages.json Find the "pages" node in the file and add the related pages and components of uView:

{
  "pages": [
    "pages/index/index",
    "pages/crop/crop"
    // 注意查看 uView 官方文档，将相关页面和组件添加到 pages 节点中
  ]
}

3. Introduce it in the

main.js file uView Style file of plug-in:

import 'uview-ui/theme/index.scss';

3. Achieve picture cropping effect

1. Create a cropping page

Create in the project root directory

crop folder, create the crop.vue file under this folder to display the image cropping effect.

<template>
  <view>
    <u-cropper @crop="onCrop" @cancel="onCancel" :aspectRatio="aspectRatio" :src="src"></u-cropper>
  </view>
</template>

<script>
export default {
  data() {
    return {
      aspectRatio: 1,  // 裁剪框的宽高比
      src: ''  // 原始图片路径
    }
  },
  methods: {
    onCrop(event) {
      console.log('裁剪完成', event);
    },
    onCancel() {
      console.log('取消裁剪');
    }
  }
}
</script>

<style></style>

2. Use the image cropping function

In the

crop page created in the previous step, we used the u-cropper component to implement the image Cropping function. Next, we need to pass the image path when jumping to the page.

In the

index.vue file, find the click event of the button that jumps to the cropping page, and pass the image path parameter in it.

<script>
export default {
  methods: {
    toCrop() {
      uni.navigateTo({
        url: `/pages/crop/crop?src=${encodeURIComponent('图片路径')}`
      });
    }
  }
}
</script>

In the

crop.vue file, we use the @crop event to listen for the callback of cropping completion, and the @cancel event to listen for the callback Callback to cancel cropping. In these two callbacks, you can perform corresponding operations as needed.

So far, we have completed the work of achieving image cropping effects in uniapp. Through the above steps, you can freely use the image cropping function in your uniapp project.

I hope this article can be helpful to you. If you have any questions, please leave a message for discussion.

The above is the detailed content of How to achieve image cropping effect in uniapp. For more information, please follow other related articles on the PHP Chinese website!