A flutter package which will help you to generate pin code fields

September 13, 2020 packages, Packages, Pin Code

A flutter package which will help you to generate pin code fields with beautiful design and animations. Can be useful for OTP or pin code inputs

Features

Automatically focuses the next field on typing and focuses previous field on deletation
Can be set to any length. (3-6 fields recommended)
3 different shapes for text fields
Highly customizable
3 different types of animation for input texts
Animated active, inactive, selected and disabled field color switching
Autofocus option
Otp-code pasting from clipboard
iOS autofill support
Error animation. Currently have shake animation only. Watch the example app for how to integrate.
Works with Flutter’s Form. You can use Form validator right off the bat.
Get currently typed text and use your condition to validate it. (for example: if (currentText.length != 6 || currentText != “your desired code”))

Getting Started

Demo

Different Shapes

Notes

To enable “Fill color” for each cells, enableActiveFill must be set to true. The default value is false.
To change the keyboard type, for example to use only number keyboard, or only for email use textInputType parameter, default is [TextInputType.visiblePassword]
FocosNode and TextEditingController will get disposed automatically. Use autoDisposeControllers = false to disable it.
to use v5.0.0 or above, developers must have Flutter SDK 1.20.0 or above.

Properties

  /// The [BuildContext] of the application
  final BuildContext appContext;

  /// length of how many cells there should be. 3-8 is recommended by me
  final int length;

  /// you already know what it does i guess 😛 default is false
  final bool obsecureText;

  /// returns the current typed text in the fields
  final ValueChanged<String> onChanged;

  /// returns the typed text when all pins are set
  final ValueChanged<String> onCompleted;

  /// returns the typed text when user presses done/next action on the keyboard
  final ValueChanged<String> onSubmitted;

  /// the style of the text, default is [ fontSize: 20, color: Colors.black, fontWeight: FontWeight.bold]
  final TextStyle textStyle;

  /// the style of the pasted text, default is [fontWeight: FontWeight.bold] while
  /// [TextStyle.color] is [ThemeData.accentColor]
  final TextStyle pastedTextStyle;

  /// background color for the whole row of pin code fields. Default is [Colors.white]
  final Color backgroundColor;

  /// This defines how the elements in the pin code field align. Default to [MainAxisAlignment.spaceBetween]
  final MainAxisAlignment mainAxisAlignment;

  /// [AnimationType] for the text to appear in the pin code field. Default is [AnimationType.slide]
  final AnimationType animationType;

  /// Duration for the animation. Default is [Duration(milliseconds: 150)]
  final Duration animationDuration;

  /// [Curve] for the animation. Default is [Curves.easeInOut]
  final Curve animationCurve;

  /// [TextInputType] for the pin code fields. default is [TextInputType.visiblePassword]
  final TextInputType textInputType;

  /// If the pin code field should be autofocused or not. Default is [false]
  final bool autoFocus;

  /// Should pass a [FocusNode] to manage it from the parent
  final FocusNode focusNode;

  /// A list of [TextInputFormatter] that goes to the TextField
  final List<TextInputFormatter> inputFormatters;

  /// Enable or disable the Field. Default is [true]
  final bool enabled;

  /// [TextEditingController] to control the text manually. Sets a default [TextEditingController()] object if none given
  final TextEditingController controller;

  /// Enabled Color fill for individual pin fields, default is [false]
  final bool enableActiveFill;

  /// Auto dismiss the keyboard upon inputting the value for the last field. Default is [true]
  final bool autoDismissKeyboard;

  /// Auto dispose the [controller] and [FocusNode] upon the destruction of widget from the widget tree. Default is [true]
  final bool autoDisposeControllers;

  /// Configures how the platform keyboard will select an uppercase or lowercase keyboard.
  /// Only supports text keyboards, other keyboard types will ignore this configuration. Capitalization is locale-aware.
  /// - Copied from 'https://api.flutter.dev/flutter/services/TextCapitalization-class.html'
  /// Default is [TextCapitalization.none]
  final TextCapitalization textCapitalization;

  final TextInputAction textInputAction;

  /// Triggers the error animation
  final StreamController<ErrorAnimationType> errorAnimationController;

  /// Callback method to validate if text can be pasted. This is helpful when we need to validate text before pasting.
  /// e.g. validate if text is number. Default will be pasted as received.
  final bool Function(String text) beforeTextPaste;

  /// Method for detecting a pin_code form tap
  /// work with all form windows
  final Function onTap;

  /// Configuration for paste dialog. Read more [DialogConfig]
  final DialogConfig dialogConfig;

  /// Theme for the pin cells. Read more [PinTheme]
  final PinTheme pinTheme;

  /// Brightness dark or light choices for iOS keyboard.
  final Brightness keyboardAppearance;

  /// Validator for the [TextFormField]
  final FormFieldValidator<String> validator;

  /// An optional method to call with the final value when the form is saved via
  /// [FormState.save].
  final FormFieldSetter<String> onSaved;

  /// enables auto validation for the [TextFormField]
  /// Default is false
  final bool autoValidate;

  /// The vertical padding from the [PinCodeTextField] to the error text
  /// Default is 16.
  final double errorTextSpace;

PinTheme

/// Colors of the input fields which have inputs. Default is [Colors.green]
  final Color activeColor;

  /// Color of the input field which is currently selected. Default is [Colors.blue]
  final Color selectedColor;

  /// Colors of the input fields which don't have inputs. Default is [Colors.red]
  final Color inactiveColor;

  /// Colors of the input fields if the [PinCodeTextField] is disabled. Default is [Colors.grey]
  final Color disabledColor;

  /// Colors of the input fields which have inputs. Default is [Colors.green]
  final Color activeFillColor;

  /// Color of the input field which is currently selected. Default is [Colors.blue]
  final Color selectedFillColor;

  /// Colors of the input fields which don't have inputs. Default is [Colors.red]
  final Color inactiveFillColor;

  /// Border radius of each pin code field
  final BorderRadius borderRadius;

  /// [height] for the pin code field. default is [50.0]
  final double fieldHeight;

  /// [width] for the pin code field. default is [40.0]
  final double fieldWidth;

  /// Border width for the each input fields. Default is [2.0]
  final double borderWidth;

  /// this defines the shape of the input fields. Default is underlined
  final PinCodeFieldShape shape;

DialogConfig

/// title of the [AlertDialog] while pasting the code. Default to [Paste Code]
  final String dialogTitle;

  /// content of the [AlertDialog] while pasting the code. Default to ["Do you want to paste this code "]
  final String dialogContent;

  /// Affirmative action text for the [AlertDialog]. Default to "Paste"
  final String affirmativeText;

  /// Negative action text for the [AlertDialog]. Default to "Cancel"
  final String negativeText;

  /// The default dialog theme, should it be iOS or other(including web and Android)
  final Platform platform; //enum Platform { iOS, other } other indicates for web and android

The pin code text field widget example

PinCodeTextField(
  length: 6,
  obsecureText: false,
  animationType: AnimationType.fade,
  pinTheme: PinTheme(
    shape: PinCodeFieldShape.box,
    borderRadius: BorderRadius.circular(5),
    fieldHeight: 50,
    fieldWidth: 40,
    activeFillColor: Colors.white,
  ),
  animationDuration: Duration(milliseconds: 300),
  backgroundColor: Colors.blue.shade50,
  enableActiveFill: true,
  errorAnimationController: errorController,
  controller: textEditingController,
  onCompleted: (v) {
    print("Completed");
  },
  onChanged: (value) {
    print(value);
    setState(() {
      currentText = value;
    });
  },
  beforeTextPaste: (text) {
    print("Allowing to paste $text");
    //if you return true then it will show the paste confirmation dialog. Otherwise if false, then nothing will happen.
    //but you can show anything you want here, like your pop up saying wrong paste format or etc
    return true;
  },
)

Shape can be among these 3 types

enum PinCodeFieldShape { box, underline, circle }

Animations can be among these 3 types

enum AnimationType { scale, slide, fade, none }

Trigger Error animation

Create a StreamController

StreamController<ErrorAnimationType> errorController = StreamController<ErrorAnimationType>();

And pass the controller like this.

PinCodeTextField(
  length: 6,
  obsecureText: false,
  animationType: AnimationType.fade,
  animationDuration: Duration(milliseconds: 300),
  errorAnimationController: errorController, // Pass it here
  onChanged: (value) {
    setState(() {
      currentText = value;
    });
  },
)

Then you can trigger the animation just by writing this:

errorController.add(ErrorAnimationType.shake); // This will shake the pin code field

This full code is from the example folder. You can run the example to see.

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: PinCodeVerificationScreen(
          "+8801376221100"), // a random number, please don't call xD
    );
  }
}

class PinCodeVerificationScreen extends StatefulWidget {
  final String phoneNumber;

  PinCodeVerificationScreen(this.phoneNumber);

  @override
  _PinCodeVerificationScreenState createState() =>
      _PinCodeVerificationScreenState();
}

class _PinCodeVerificationScreenState extends State<PinCodeVerificationScreen> {
  var onTapRecognizer;

  TextEditingController textEditingController = TextEditingController()
    ..text = "123456";

  StreamController<ErrorAnimationType> errorController;

  bool hasError = false;
  String currentText = "";
  final GlobalKey<ScaffoldState> scaffoldKey = GlobalKey<ScaffoldState>();
  final formKey = GlobalKey<FormState>();

  @override
  void initState() {
    onTapRecognizer = TapGestureRecognizer()
      ..onTap = () {
        Navigator.pop(context);
      };
    errorController = StreamController<ErrorAnimationType>();
    super.initState();
  }

  @override
  void dispose() {
    errorController.close();

    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.blue.shade50,
      key: scaffoldKey,
      body: GestureDetector(
        onTap: () {
          FocusScope.of(context).requestFocus(FocusNode());
        },
        child: Container(
          height: MediaQuery.of(context).size.height,
          width: MediaQuery.of(context).size.width,
          child: ListView(
            children: <Widget>[
              SizedBox(height: 30),
              Container(
                height: MediaQuery.of(context).size.height / 3,
                child: FlareActor(
                  "assets/otp.flr",
                  animation: "otp",
                  fit: BoxFit.fitHeight,
                  alignment: Alignment.center,
                ),
              ),
              // Image.asset(
              //   'assets/verify.png',
              //   height: MediaQuery.of(context).size.height / 3,
              //   fit: BoxFit.fitHeight,
              // ),
              SizedBox(height: 8),
              Padding(
                padding: const EdgeInsets.symmetric(vertical: 8.0),
                child: Text(
                  'Phone Number Verification',
                  style: TextStyle(fontWeight: FontWeight.bold, fontSize: 22),
                  textAlign: TextAlign.center,
                ),
              ),
              Padding(
                padding:
                    const EdgeInsets.symmetric(horizontal: 30.0, vertical: 8),
                child: RichText(
                  text: TextSpan(
                      text: "Enter the code sent to ",
                      children: [
                        TextSpan(
                            text: widget.phoneNumber,
                            style: TextStyle(
                                color: Colors.black,
                                fontWeight: FontWeight.bold,
                                fontSize: 15)),
                      ],
                      style: TextStyle(color: Colors.black54, fontSize: 15)),
                  textAlign: TextAlign.center,
                ),
              ),
              SizedBox(
                height: 20,
              ),
              Form(
                key: formKey,
                child: Padding(
                    padding: const EdgeInsets.symmetric(
                        vertical: 8.0, horizontal: 30),
                    child: PinCodeTextField(
                      length: 6,
                      obsecureText: false,
                      animationType: AnimationType.fade,
                      validator: (v) {
                        if (v.length < 3) {
                          return "I'm from validator";
                        } else {
                          return null;
                        }
                      },
                      pinTheme: PinTheme(
                        shape: PinCodeFieldShape.box,
                        borderRadius: BorderRadius.circular(5),
                        fieldHeight: 50,
                        fieldWidth: 40,
                        activeFillColor:
                            hasError ? Colors.orange : Colors.white,
                      ),
                      animationDuration: Duration(milliseconds: 300),
                      backgroundColor: Colors.blue.shade50,
                      enableActiveFill: true,
                      errorAnimationController: errorController,
                      controller: textEditingController,
                      onCompleted: (v) {
                        print("Completed");
                      },
                      onChanged: (value) {
                        print(value);
                        setState(() {
                          currentText = value;
                        });
                      },
                      beforeTextPaste: (text) {
                        print("Allowing to paste $text");
                        //if you return true then it will show the paste confirmation dialog. Otherwise if false, then nothing will happen.
                        //but you can show anything you want here, like your pop up saying wrong paste format or etc
                        return true;
                      },
                    )),
              ),
              Padding(
                padding: const EdgeInsets.symmetric(horizontal: 30.0),
                child: Text(
                  hasError ? "*Please fill up all the cells properly" : "",
                  style: TextStyle(color: Colors.red, fontSize: 12, fontWeight: FontWeight.w400),
                ),
              ),
              SizedBox(
                height: 20,
              ),
              RichText(
                textAlign: TextAlign.center,
                text: TextSpan(
                    text: "Didn't receive the code? ",
                    style: TextStyle(color: Colors.black54, fontSize: 15),
                    children: [
                      TextSpan(
                          text: " RESEND",
                          recognizer: onTapRecognizer,
                          style: TextStyle(
                              color: Color(0xFF91D3B3),
                              fontWeight: FontWeight.bold,
                              fontSize: 16))
                    ]),
              ),
              SizedBox(
                height: 14,
              ),
              Container(
                margin:
                    const EdgeInsets.symmetric(vertical: 16.0, horizontal: 30),
                child: ButtonTheme(
                  height: 50,
                  child: FlatButton(
                    onPressed: () {
                      formKey.currentState.validate();
                      // conditions for validating
                      if (currentText.length != 6 || currentText != "towtow") {
                        errorController.add(ErrorAnimationType
                            .shake); // Triggering error shake animation
                        setState(() {
                          hasError = true;
                        });
                      } else {
                        setState(() {
                          hasError = false;
                          scaffoldKey.currentState.showSnackBar(SnackBar(
                            content: Text("Aye!!"),
                            duration: Duration(seconds: 2),
                          ));
                        });
                      }
                    },
                    child: Center(
                        child: Text(
                      "VERIFY".toUpperCase(),
                      style: TextStyle(
                          color: Colors.white,
                          fontSize: 18,
                          fontWeight: FontWeight.bold),
                    )),
                  ),
                ),
                decoration: BoxDecoration(
                    color: Colors.green.shade300,
                    borderRadius: BorderRadius.circular(5),
                    boxShadow: [
                      BoxShadow(
                          color: Colors.green.shade200,
                          offset: Offset(1, -2),
                          blurRadius: 5),
                      BoxShadow(
                          color: Colors.green.shade200,
                          offset: Offset(-1, 2),
                          blurRadius: 5)
                    ]),
              ),
              SizedBox(
                height: 16,
              ),
              Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: <Widget>[
                  FlatButton(
                    child: Text("Clear"),
                    onPressed: () {
                      textEditingController.clear();
                    },
                  ),
                  FlatButton(
                    child: Text("Set Text"),
                    onPressed: () {
                      textEditingController.text = "123456";
                    },
                  ),
                ],
              )
            ],
          ),
        ),
      ),
    );
  }
}