Generate forms with native look and feel in a breeze
- Picker
- DatePicker
- TimePicker
- Input
- Link
- Separator
- Switch
- Android and IOS support, Yeah Baby!
- Pleasant Defaults, totally overridable
- Doesn't have dependencies
- Use your own icon pack
- Easy to use and clean, react style syntax
- Automatic events handling
- Supports custom fields and styles without adding any weird syntax (just create a react component)
- Applies by default the current OS style
- Inspired by tcomb, the good parts
- Performances: just the field changed gets a setState
- You don't need to create a 'Model' or a 'Struct' that contains your data, just create a form component (the React's way)
- Validate InputFields based on keyboardType (can be overridden using validationFunction)
- Multiple validators
- Reset/Set Fields programmatically (setValue, setDate, setTime, focus)
- Custom Wrapper for Picker & DatePicker Components (iOS Only)
My blogpost about React Native Form Generator
npm install --save react-native-form-generator
- Pull requests are very very welcome. They make my day ;).
- Master should be considered 'unstable' even if I do my best to keep it nice and safe.
- Every release has its own branch.
- Slider hasn't been created.
- I have to document the code properly and do some housekeeping, i apologize in advance.
Please check the folder examples for an always up to date use case.
the example below generates the form you see in the animation
/*
This is a view i use in a test app,
very useful to list all the use cases
*/
import React from 'react';
import {
AppRegistry,
StyleSheet,
Text,
View,ScrollView,
} from 'react-native';
import { Form,
Separator,InputField, LinkField,
SwitchField, PickerField,DatePickerField,TimePickerField
} from 'react-native-form-generator';
export class FormView extends React.Component{
constructor(props){
super(props);
this.state = {
formData:{}
}
}
handleFormChange(formData){
/*
formData will contain all the values of the form,
in this example.
formData = {
first_name:"",
last_name:"",
gender: '',
birthday: Date,
has_accepted_conditions: bool
}
*/
this.setState({formData:formData})
this.props.onFormChange && this.props.onFormChange(formData);
}
handleFormFocus(e, component){
//console.log(e, component);
}
openTermsAndConditionsURL(){
}
render(){
return (<ScrollView keyboardShouldPersistTaps={true} style={{paddingLeft:10,paddingRight:10, height:200}}>
<Form
ref='registrationForm'
onFocus={this.handleFormFocus.bind(this)}
onChange={this.handleFormChange.bind(this)}
label="Personal Information">
<Separator />
<InputField
ref='first_name'
label='First Name'
placeholder='First Name'
helpText={((self)=>{
if(Object.keys(self.refs).length !== 0){
if(!self.refs.registrationForm.refs.first_name.valid){
return self.refs.registrationForm.refs.first_name.validationErrors.join("\n");
}
}
// if(!!(self.refs && self.refs.first_name.valid)){
// }
})(this)}
validationFunction={[(value)=>{
/*
you can have multiple validators in a single function or an array of functions
*/
if(value == '') return "Required";
//Initial state is null/undefined
if(!value) return true;
// Check if First Name Contains Numbers
var matches = value.match(/\d+/g);
if (matches != null) {
return "First Name can't contain numbers";
}
return true;
}, (value)=>{
///Initial state is null/undefined
if(!value) return true;
if(value.indexOf('4')!=-1){
return "I can't stand number 4";
}
return true;
}]}
/>
<InputField ref='last_name' placeholder='Last Name'/>
<InputField
multiline={true}
ref='other_input'
placeholder='Other Input'
helpText='this is an helpful text it can be also very very long and it will wrap' />
<Separator />
<LinkField label="test test test" onPress={()=>{}}/>
<SwitchField label='I accept Terms & Conditions'
ref="has_accepted_conditions"
helpText='Please read carefully the terms & conditions'/>
<PickerField ref='gender'
label='Gender'
options={{
"": '',
male: 'Male',
female: 'Female'
}}/>
<DatePickerField ref='birthday'
minimumDate={new Date('1/1/1900')}
maximumDate={new Date()}
placeholder='Birthday'/>
<TimePickerField ref='alarm_time'
placeholder='Set Alarm'/>
<DatePickerField ref='meeting'
minimumDate={new Date('1/1/1900')}
maximumDate={new Date()} mode="datetime" placeholder='Meeting'/>
</Form>
<Text>{JSON.stringify(this.state.formData)}</Text>
</ScrollView>);
}
}Form automatically attaches on change events so you just have to attach an handle to the onFocus attibute of Form to monitor all the changes.
It's just a wrapper that allows you to attach onFocus (used to track focus events and keyboard events) and onChange (used to track changes in every field)
- Every field that has to propagate its value in the form MUST have a ref attribute. (Separator and LinkField don't have a ref). Check the example to understand the use of the ref attribute.
- All the components provided use Field as wrapper in order to have the following props.
| Prop (parameters) | Description |
|---|---|
| helpText | String shown as text under the component |
| helpTextComponent | Custom component that replaces the one provided |
| onPress | onPress method |
<Separator
label="Example" // optional: if present it will show the text
/>Input fields can be used to receive text, you can add icons (a react component) to the left and the right side of the field.
InputField can validate values based on keyboardType property, validation is not "aggressive", just changes a value inside the class, you can access the value using the ref (ex. this.ref.example_input_field.valid).
InputField automatically provides the attibutes valid and validationErrors to guarantee full control to the developer.
you can customize your validation function by adding a validationFunction prop to the component. validationFunction supports also an array of validators.
Validators are simple functions have one paramenter (value) and that return true or a string containing an error.
let workingValidator = (value)=>{
if(value == '') return "Required";
//Initial state is null/undefined
if(!value) return true;
var matches = value.match(/\d+/g);
if (matches != null) {
return "First Name can't contain numbers";
}
return true;
}react-native-form-generator doesn't depend on any icon library, that gives you freedom of adding any icon or react component you want.
look at the example here.
<InputField
label='Example' // if label is present the field is rendered with the value on the left (see First Name example in the gif), otherwise its rendered with textinput at full width (second name in the gif).
ref='example_input_field' // used in onChange event to collect the value
value='default_value' // used as initial value
keyboardType = '' // undefined, 'email-address',
validationFunction = {(value)=>{return true;}}
iconRight={
<Icon name='checkmark-circled'
size={30}
style={[
{marginTop:7, color:"#61d062" },
((self)=>{
//i can change the style of the component related to the attibute of example_input_field
if(!!(self.refs && self.refs.example_input_field)){
if(!self.refs.example_input_field.valid) return {color:'#d52222'}
}
}
)(this)]}
/>
} //React Component
/>All the props are passed down to the underlying TextInput Component
| Prop (parameters) | Description |
|---|---|
| label | Text to show in the field, if exists will move the textinput on the right, providing also the right alignment |
| iconLeft | React component, shown on the left of the field, the component needs to have a prop size to allow the inputText to resize properly |
| iconRight | React component, shown on the right of the field, the component needs to have a prop size to allow the inputText to resize properly |
| validationFunction | Function or array of functions, used to pass custom validators to the component |
| keyboardType | possible values: undefined, email-address |
| ref methods | Description |
|---|---|
| setValue | Sets the value programmatically |
| focus | Focus the textinput component |
| Prop (parameters) | Description |
|---|---|
| onValueChange(value) | triggered at every value change, returns the new value of the field |
| value | Initial value of the component (Boolean) |
| Prop (parameters) | Description |
|---|---|
| onValueChange(value) | triggered at every value change, returns the new value of the field |
| value | Initial value of the component |
| options=[{label:"test",value="Test"},...] | All the possible options, array of objects |
| iconRight | React component, shown on the left of the text field (i suggest Ionicons 'ios-arrow-right' for a nice iOS effect) |
| pickerWrapper | Optional, Custom wrapper of the picker, check the example |
Every prop is passed down to the underlying DatePickerIOS/DatePickerAndroid component.
| Prop (parameters) | Description |
|---|---|
| onValueChange(date) | triggered at every value change, returns the new value of the field |
| date | Initial date of the component, defaults to (new Date()) |
| iconRight | React component, shown on the left of the text field (i suggest Ionicons 'ios-arrow-right' for a nice iOS effect) |
| dateTimeFormat | Optional, Custom date formatter |
| pickerWrapper | Optional, Custom wrapper of the picker, check the example |
| prettyPrint | Boolean, if true the component returns a string formatted using dateTimeFormat, if false a Date object is returned |
| placeholderComponent | Substitutes the component used to render the placeholder |
| placeholderStyle | Used to style the placeholder |
| valueStyle | Used to style the field's value |
Every prop is passed down to the underlying DatePickerIOS/DatePickerAndroid component. Mode is set to 'time'
| Prop (parameters) | Description |
|---|---|
| onValueChange(date) | triggered at every value change, returns the new value of the field |
| date | Initial date of the component, defaults to (new Date()) |
| iconRight | React component, shown on the left of the text field (i suggest Ionicons 'ios-arrow-right' for a nice iOS effect) |
| dateTimeFormat | Optional, Custom date formatter |
| pickerWrapper | Optional, Custom wrapper of the picker, check the example |
| prettyPrint | Boolean, if true the component returns a string formatted using dateTimeFormat, if false a Date object is returned |
| placeholderComponent | Substitutes the component used to render the placeholder |
| placeholderStyle | Used to style the placeholder |
| valueStyle | Used to style the field's value |
Every prop is passed down to the underlying DatePickerIOS component.
| Prop (parameters) | Description |
|---|---|
| label | Text to show in the field |
| iconLeft | React component, shown on the left of the text field |
| iconRight | React component, shown on the left of the text field (i suggest Ionicons 'ios-arrow-right' for a nice iOS effect) |
react-native-form-generator ships with an implementation ok KeyboardAwareScrollView that make handling keyboard events a breeze. check here https://medium.com/@michaelcereda/react-native-forms-the-right-way-315802f989d6#.p9oj79vt3
With react-native-form-generator is extremely easy to create your own custom fields. You just need to know that:
- Every field is a react component
- Evey field will receive 3 props from the Form object:
- fieldRef: contains the reference of the field (workaround on a react-native bug).
- onChange: must be called every time i want to update the values inside the form component. (required)
- onValueChange: can be used whenever you prefer to pass the values to another component.
Example
'use strict';
import {Field} from '../lib/Field';
export class SimpleInputField extends React.Component{
constructor(props){
super();
}
}
handleChange(event){
var value = event.nativeEvent.text;
this.setState({value:value});
// This updates values in form everytime i update
if(this.props.onChange) this.props.onChange(this.props.fieldRef, value);
if(this.props.onValueChange) this.props.onValueChange(value);
}
render(){
return(<Field>
<TextInput
{...this.props}
ref='inputBox'
onChange={this.handleChange.bind(this)}
placeholder={this.props.placeholder}
value={this.state.value}
/>
</Field>
)
}
}You can decide to wrap every field in a component to mantain design uniformity and avoid repetitions (ex. Icons ?!).
Battle tested example
import {PickerField, LinkField} from 'react-native-form-generator';
import Icon from 'react-native-vector-icons/Ionicons';
let {
StyleSheet
} = React;
export class WrappedLinkField extends React.Component{
render(){
return <LinkField
label={this.props.label}
onPress={this.props.onPress}
iconRight={<Icon name='ios-arrow-right'
size={30}
/>
}
}
export class WrappedPickerField extends React.Component{
render(){
return <PickerField
fieldRef = {this.props.fieldRef}
value={this.props.value}
placeholder={this.props.placeholder}
options={this.props.options}
onChange={this.props.onChange}
onValueChange={this.props.onValueChange}
iconRight={
<Icon name='ios-arrow-right'
size={30}
style={[
formStyles.alignRight,{color: '#C7C7CC'},
this.props.iconStyle]}/>
}
/>
}
}
let formStyles = StyleSheet.create({
alignRight:{
marginTop: 7, position:'absolute', right: 10
}
});