django show last 3 char of string in admin fields-CodePudding

database

| id   | salary_number |
| ---  | ------------- |
| 1    | 1042          |

models.py

class user(AbstractUser):
    salary_number = models.CharField(max_length=4, unique=True, null=True, blank=True)    

    def __str__(self):
         return f'{self.salary_number[-3:]}'

admin.py

class UserAdmin(admin.ModelAdmin):
    fields = ('salary_number[-3:]',)

def get_readonly_fields(self, request, obj=None):
        return ['salary_number'] if obj else []

I would like to show Salary number: 042 in admin fields instead of 1042. Is it possible?

How can I add number 1 to the salary_number after click save new form?

CodePudding user response：

You can use '__str__' as field:

class UserAdmin(admin.ModelAdmin):
    readonly_fields = ('__str__',)

But this makes it unclear what the field is doing. Likely it is better to make a callable that describes that this is the last digits of the salary number:

class UserAdmin(admin.ModelAdmin):
    readonly_fields = ('salary_digits',)
    
    @admin.display(description='Salary digits')
    def salary_digits(self, obj):
        if obj.salary_number is not None:
            return obj.salary_number[-3:]