Android Form Validator Library

Library for validating forms may have many fields at once

Sample

Code

class MainActivity : AppCompatActivity() {

    private val validator = Validator()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        btn.setOnClickListener {
            if (formsValidated()) {
                // Do your magic
            }
        }
    }

    private fun formsValidated(): Boolean {
        validator.buildRulesFor(field)
            .required()
            .min(15)

        validator.buildRulesFor(field2)
            .required()
            .max(5)
            .validEmail()
            .onError {
                Toast.makeText(this, it, Toast.LENGTH_SHORT).show()
            }

        return validator.check()
    }
}

Getting Started

Installation

Adding into your project

• Using jcenter Add this line into your app build.gradle

implementation 'dev.poteto:formvalidator:0.0.9'

• Using jitpack repository Add this the code into your project build.gradle

allprojects {
    repositories {
        ...
        maven { url "https://jitpack.io" }
    }
}

Then add this into your app build.gradle

implementation 'com.github.rendyyangasli:android-form-validator:0.0.9'

Usage

Default Usage

You must invoke method buildRulesFor() in one statement only.

// Create the validator instance
val validator = Validator(INDONESIAN) 
// Use this argument if you prefer using indonesian message over english error message
// You can left the argument empty, it will using english error message as default

// Find your views with traditional way
val editText = findViewById<EditText>(R.id.field1)
validator.buildRulesFor(editText)
    .required()
    .min(10)
        
// Or you prefer for using kotlin views extension
validator.buildRulesFor(field1, DataType.INT)
    .required()
    .min(10)

// Then check your all forms 
if (validator.check()) {
    // Then do your magic
}

DataType is an enum class for DataType.STRING and DataType.INT type If you are not passing the DataType parameter, the STRING will be used as a default DataType

Or if you not want to invoke buildRulesFor() per statement, you can chain all the validation rules, you can invoke the build() method, then build your validation rules again Example using the build() method

val validator = Validator();
validator.buildRulesFor(editText1)
    .required()
    .min(10)
    .build() // Your rules validation has been reset here
    .buildRulesFor(editText2) 
    .required()
    .build()

buildRulesFor() method just only accept 2 types of validation, i.e CharSequence and EditText

Passing EditText into the first parameter will automatically setting the error message for you. If you wrap your EditText inside TextInputLayout, it will automatically setting the error message into your TextInputLayout instead of EditText. Yeahhh :))

Then, passing CharSequence will not show your errors into the views. you must invoke onError lamda to catch the error.

Custom Validation Rule

If you need to write your own validation rules, then you can invoke customRule() method then implements the ValidationRule interface members

validator.buildRulesFor(field)
    .required()
    .customRule(object : ValidationRule {
        override fun check(): Boolean {
            return field1.text == field2.text
        }
        
        override fun getMessage(): String {
            return "value for field 1 must be the same with field 2"
        }
    })

Custom Error Callback

validator.buildRulesFor(string)
    .required()
    .onError { msg -> 
        Toast.make(context, msg, Toast.LENGTH_SHORT).show()
    }

Custom Error Messages

It's so easy for you to customize the error message, you just need to create object and implement the ValidationMessages interface, then you should calling it when creating the Validator instance. e.g

val customMessage = object : ValidationMessages {
    // you must implement the methods defined there
}

val validator = Validator(customMessage)

Then you will be able to use the validator as usually with customized error messages. this is very useful when you're creating multilinguism app

Available Error Messages Languages

• English (default)
• Indonesian (INDONESIAN)

We need help to supporting another language

Available Validation Rules

• required() mark the field as required
• validEmail() to checking email
• min(minimalValue) to checking minimal value
• max(maximalValue) to limit the user input
• range(min, max) range user input, can be as characters or integer
• phone() to check user input is match with phone number format

Milestones

Check the issues