FlutterBlue

virtual_keyboard

Introduction

A simple package for dispaying virtual keyboards on a devices like kiosks and ATMs. The library is written in Dart and has no native code dependancy.

Virtual keyboard provides a core set of functionality to display onscreen virtual keyboards. Managing the events sould be done on the project level.

Reference

VirtualKeyboard

Flutter widget to show virtual keyboards.

// Keyboard Type: Can be Numeric or Alphanumeric.
VirtualKeyboardType type

// Callback for Key press event. Called with pressed `Key` object.
Function onKeyPress;

// Virtual keyboard height. Default is 300.
double height;

// Color for key texts and icons.
Color textColor;

// Font size for keyboard keys.
double fontSize;;

// Only Caps letters enabled.
bool alwaysCaps;;

VirtualKeyboardType

enum of Available Virtual Keyboard Types.

// Numeric only.
VirtualKeyboardType.Numeric

// Alphanumeric: letters`[A-Z]` + numbers`[0-9]` + `@` + `.`.
VirtualKeyboardType.Alphanumeric

VirtualKeyboardKey

Virtual Keyboard key.

// The text of the key. 
String text

// The capitalized text of the key. 
String capsText;

// Action or String
VirtualKeyboardKeyType keyType;

// Action of the key.
VirtualKeyboardKeyAction action;

VirtualKeyboardKeyType

Type for virtual keyboard key.

// Can be an action key - Return, Backspace, etc.
VirtualKeyboardKeyType.Action

// Keys that have text values - letters, numbers, comma ...
VirtualKeyboardKeyType.String

VirtualKeyboardKeyAction

/// Virtual keyboard actions.
enum VirtualKeyboardKeyAction { Backspace, Return, Shift, Space }

Usage

Show Alphanumeric keyboard with default view

// Wrap the keyboard with Container to set background color.
Container(
            // Keyboard is transparent
            color: Colors.deepPurple,
            child: VirtualKeyboard(
                // Default height is 300
                height: 350,
                // Default is black
                textColor: Colors.white,
                // Default 14
                fontSize: 20,
                // [A-Z, 0-9]
                type: VirtualKeyboardType.Alphanumeric,
                // Callback for key press event
                onKeyPress: _onKeyPress),
          )

Show Numeric keyboard with default view

Container(
            // Keyboard is transparent
            color: Colors.red,
            child: VirtualKeyboard(
                // [0-9] + .
                type: VirtualKeyboardType.Numeric,
                // Callback for key press event
                onKeyPress: (key) => print(key.text)),
          )

Show Alphanumeric keyboard with customized keys

 Container(
            color: Colors.deepPurple,
            child: VirtualKeyboard(
                height: keyboardHeight,
                textColor: Colors.white,
                fontSize: 20,
                builder: _builder,
                type: VirtualKeyboardType.Numeric,
                onKeyPress: _onKeyPress),
          )

  /// Builder for keyboard keys.
  Widget _builder(BuildContext context, VirtualKeyboardKey key) {
    Widget keyWidget;

    switch (key.keyType) {
      case VirtualKeyboardKeyType.String:
        // Draw String key.
        keyWidget = _keyboardDefaultKey(key);
        break;
      case VirtualKeyboardKeyType.Action:
        // Draw action key.
        keyWidget = _keyboardDefaultActionKey(key);
        break;
    }

    return keyWidget;
  }

onKeyPressed event basic ussage example

// Just local variable. Use Text widget or similar to show in UI.
String text;

  /// Fired when the virtual keyboard key is pressed.
_onKeyPress(VirtualKeyboardKey key) {
if (key.keyType == VirtualKeyboardKeyType.String) {
    text = text + (shiftEnabled ? key.capsText : key.text);
} else if (key.keyType == VirtualKeyboardKeyType.Action) {
    switch (key.action) {
    case VirtualKeyboardKeyAction.Backspace:
        if (text.length == 0) return;
        text = text.substring(0, text.length - 1);
        break;
    case VirtualKeyboardKeyAction.Return:
        text = text + '\n';
        break;
    case VirtualKeyboardKeyAction.Space:
        text = text + key.text;
        break;
    case VirtualKeyboardKeyAction.Shift:
        shiftEnabled = !shiftEnabled;
        break;
    default:
    }
}
// Update the screen
setState(() {});
}