i have weird results that i want to understand .

1- i have image in my device gallery .

2- I decided to find out the height of an image using image details

3- the given height was 1920

4- Out of curiosity, I wrote the following code

Container(
color:Colors.yellow,
width:300,
height:1920, // i know it is big height but it is the same image height 
)

5- the output of height was completely bigger than image height

Question : why it was bigger ? Isn't it the same height?

CodePudding user response：

Because the flutter uses logical pixel unit to render ui, but you read the image sizes in pixel unit.

You can read more about logical pixel in flutter documents here: https://api.flutter.dev/flutter/dart-ui/FlutterView/devicePixelRatio.html

To fix that, you need to divide pixel size by devicePixelRatio like this:

Container(
    color:Colors.yellow,
    width:300,
    height:1920/MediaQuery.of(context).devicePixelRatio, 
)