Summary of issues related to image processing in WeChat mini programs

巴扎黑
Release: 2017-05-21 19:04:31
Original
2858 people have browsed it

Abstract: During the development process of small programs and page layout, we often encounter some image processing problems. For example, if the image is not of fixed height and height, but the image setting is fixed The height and width of the original image are not proportional to the fixed height and width set by the image, then this...

During the development process of small programs and page layout, we often encounter some image processing problems. For example, if the image is not of fixed height and height, but the image is set to a fixed height and width, then the original image will be relatively If the fixed height and width set by the image are not of equal proportion, the image will be deformed and unclear. At this time, you can use the following proportional scaling method to scale the image so that the image does not deform. Or dynamically obtain the height and width of the image through the bindload method of the image, and dynamically set the height and width of the image so that the height and width of the image layout are equal to the height and width of the original image.

Summary of issues related to image processing in WeChat mini programs
1. Image proportional scaling tool

//Util.js


class Util{  
    /*** 
     * 按照显示图片的宽等比例缩放得到显示图片的高 
     * @params originalWidth  原始图片的宽 
     * @params originalHeight 原始图片的高 
     * @params imageWidth     显示图片的宽,如果不传就使用屏幕的宽 
     * 返回图片的宽高对象 
    ***/  
    static imageZoomHeightUtil(originalWidth,originalHeight,imageWidth){  
        let imageSize = {};  
        if(imageWidth){  
            imageSize.imageWidth = imageWidth;  
            imageSize.imageHeight = (imageWidth * originalHeight) / originalWidth;  
        }else{//如果没有传imageWidth,使用屏幕的宽  
            wx.getSystemInfo({    
                success: function (res) {    
                    imageWidth = res.windowWidth;    
                    imageSize.imageWidth = imageWidth;  
                    imageSize.imageHeight = (imageWidth * originalHeight) / originalWidth;  
                }    
            });  
        }  
        return imageSize;  
    }  
    /*** 
     * 按照显示图片的高等比例缩放得到显示图片的宽 
     * @params originalWidth  原始图片的宽 
     * @params originalHeight 原始图片的高 
     * @params imageHeight    显示图片的高,如果不传就使用屏幕的高 
     * 返回图片的宽高对象 
    ***/  
    static imageZoomWidthUtil(originalWidth,originalHeight,imageHeight){  
        let imageSize = {};  
        if(imageHeight){  
            imageSize.imageWidth = (imageHeight *originalWidth) / originalHeight;  
            imageSize.imageHeight = imageHeight;  
        }else{//如果没有传imageHeight,使用屏幕的高  
            wx.getSystemInfo({    
                success: function (res) {    
                    imageHeight = res.windowHeight;  
                    imageSize.imageWidth = (imageHeight *originalWidth) / originalHeight;  
                    imageSize.imageHeight = imageHeight;  
                }    
            });  
        }  
        return imageSize;  
    }  
}  
export default Util;
Copy after login
2. Use the image component to load the image, dynamically obtain the height and width of the image through bindload, and dynamically set the height and width of the image


<image bindload="imageLoad" style="width:{{imageWidth}}px;;height:{{imageHeight}}px;" src="../pro.png"/>
Copy after login
index.js code is as follows


import Util from &#39;../common/Util&#39;;  
Page({  
  data:{  
        imageWidth:0,  
        imageHeight:0  
  },  
  imageLoad: function (e) {    
        //获取图片的原始宽度和高度  
        let originalWidth = e.detail.width;  
        let originalHeight = e.detail.height;  
        //let imageSize = Util.imageZoomHeightUtil(originalWidth,originalHeight);  
        //let imageSize = Util.imageZoomHeightUtil(originalWidth,originalHeight,375);  
        let imageSize = Util.imageZoomWidthUtil(originalWidth,originalHeight,145);  
        this.setData({imageWidth:imageSize.imageWidth,imageHeight:imageSize.imageHeight});    
  }  
})
Copy after login

The above is the detailed content of Summary of issues related to image processing in WeChat mini programs. For more information, please follow other related articles on the PHP Chinese website!

source:php.cn
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template