TEXTVIEW.md

TextView Validation

FormEditText and FormAutoCompleteTextView are predefined TextView widgets that implement validatable interface.

Attributes

Attribute	Description
validationType	see TextView validationType Values
errorMessage	message if the field is invalid
requiredErrorMessage	message if the field is empty
customValidationType	a string for custom validation (see usage below)

TextView validationType Values

Type	Description	Required attributes
required	validates required fields	_
numeric	validates numeric only	_
alpha	validates alpha only	_
alphaNumeric	validates alpha numeric	_
email	validates email	_
creditCard	validates credit card using Luhn Algorithm	_
phone	validates phone	_
domainName	validates domain name	_
ipAddress	validates IP address	_
webUrl	validates web URL	_
personName	validates person name	_
personFullName	validates person full name	_
regex	validates a REGEX	- regex
numericRange	validates numeric range	- minNumber - maxNumber .
floatNumericRange	validates floating-point ranges	- floatMinNumber - floatMaxNumber
date	validates date	- dateFormat

Custom Validators

There are 2 approaches to create a cutom validator

• Extend TextValidator to use the validator programmatically.
• Extend CustomValidator to use the validator in XML.

TextValidator

class SuffixValidator(private val suffix: String, errorMessage: String) : TextValidator(errorMessage) {
    override fun isValid(text: String): Boolean = text.endsWith(suffix)
}

Use the validator

formEditText.addValidator(SuffixValidator("Must start with d."))

Note SuffixValidator is predefined in the library.

CustomValidator

CustomValidator is a validator that enables you create a custom validator to be used in XML using customValidationType attribute.

Define the custom validator by extending CustomValidator.

class NumberOneCustomValidator(errorMessage: String) : CustomValidator(errorMessage) {
    override fun customValidationType(context: Context): String {
    // use the type defined using non-translatable string to avoid mistakes
        return context.getString(R.string.custom_validator_number_one)
    }
    override fun isValid(text: String) = text == "1"
}

Declare NumberOneCustomValidator in XML

<com.sha.formvalidator.widget.FormEditText
    <!-- use the type defined using non-translatable string to avoid mistakes  -->
    app:customValidationType="@string/custom_validator_number_one" 
    ...
    />

Register custom validators. Note that it's mandatory to register custom validators to be recognized by FormValidator.

class App : Application() {
    override fun onCreate() {
      super.onCreate()
      TextViewValidators.customValidators = listOf(NumberOneCustomValidator("Value doesn't equal 1"))
   }
}