Flutter Pub: Expected a key while parsing a block mapping. path:

问题

I searched it on Stackoverflow but regarding flutter, I do not find any relevant solution, here and here may be the same question but they are not for flutter.

I'm using JSON file and register in Pubspec.ymal but showing error and also when I use an image and register it, the same error also occurs. Maybe there is a formatting mistake in it, but don't know what the problem is.this is the doc I followed.

Error on line 29, column 5 of pubspec.yaml: Expected a key while parsing a block mapping. assets: ^

This is my pubspec.yaml file

name: jsondata description: A new Flutter application.

  dependencies:  

  flutter:

  sdk: flutter

  cupertino_icons: ^0.1.0

  dev_dependencies:   

 flutter_test:

      sdk: flutter

    flutter:

    uses-material-design: true

      assets:

       - loadjson/person.json

回答1:

Spaces are significant in YAML

assets is indented too far

flutter_test:
  sdk: flutter

flutter:
  uses-material-design: true
  assets:
    - loadjson/person.json

回答2:

Error on line 29, column 4: Expected a key while parsing a block mapping. assets:

flutter: uses-material-design: true assets: - assets/images/image.jpg

In my case i just added # in front of uses-material-design: true

Try below code

flutter:   

  # uses-material-design: true 

   assets: 
    - assets/images/image.jpg

its working fine.

回答3:

In my case, uses-material-design intendation was broke. I put 1 (one) more space before it, and it worked fine.

回答4:

In My Case, the image was too large to load, decreasing dimension of image worked.

回答5:

Please make sure that we don't have unwanted whitespace since yaml structure is sensitively considering the white spaces. Please refer the documentation for more info as below link,
https://docs.ansible.com/ansible/latest/reference_appendices/YAMLSyntax.html

回答6:

It is because of the indentation of your code.The uses-material-design should be on the same line vertically as the assets:.

 uses-material-design: true

 assets:
   - images/picture.png

来源：https://stackoverflow.com/questions/50171766/flutter-pub-expected-a-key-while-parsing-a-block-mapping-path