소개

intro

A step-by-step wizard, which can help you to introduce your product or to demonstrate the usage of your application.

Features

• Step by step demonstration
• Control the demo flow
• Highlight the target widget
• Automatically calculates the location and alignment of intro card
• Customizable style and behavior
• Supports nesting of multiple demo flow
• Link between different pages or dialogs
• Full platform support

Demo

Getting started

Add this package to your project.

flutter pub add intro

Import it in your code.

import 'package:intro/intro.dart';

Usage

1. Register the Intro widget at the earliest possible widget tree node.

   Provide a IntroController that has specified the stepCount. The stepCount refers to the total number of steps in the demo flow.

runApp(Intro(
  controller: IntroController(stepCount: 5),
  child: MaterialApp(
    home: HomePage(),
  ),
));

2. Wrap the IntroStepTarget widget around each of your target widgets that you need to introduce.

IntroStepTarget(
  step: step,
  controller: Intro.of(context).controller,
  cardContents: TextSpan(
    text: "The introductory text of this step.",
  ),
  child: targetWidget,
);

3. Start the demo flow at the right time.

Intro.of(context).controller.start(context);

Decoration for intro card

Provid a IntroCardDecoration object in the cardDecoration field of the IntroStepTarget widget (specific step target) or the Intro widget (global) to describe the style or behavior for intro card.

Globally effective:

Intro(
  cardDecoration: IntroCardDecoration(
    // TODO:
    // Some attributes that need to be specifically specified.
    // For missing attributes , they will use its default value.
  ),
  // ...
);

Only effective for specific step:

IntroStepTarget(
  cardDecoration: IntroCardDecoration(
    // TODO:
    // Some attributes that need to be specifically specified.
    // For missing attributes , they will use global value (be specified in `Intro`).
  ),
  // ...
);

Attributes for IntroCardDecoration :

Decoration for highlighted widget

Provid a IntroHighlightDecoration object in the highlightDecoration field of the IntroStepTarget widget (specific step target) or the Intro widget (global) to describe the style for highlighted widget.

Globally effective:

Intro(
  highlightDecoration: IntroHighlightDecoration(
    // TODO:
    // Some attributes that need to be specifically specified.
    // For missing attributes , they will use its default value.
  ),
  // ...
);

Only effective for specific step:

IntroStepTarget(
  highlightDecoration: IntroHighlightDecoration(
    // TODO:
    // Some attributes that need to be specifically specified.
    // For missing attributes , they will use global value (be specified in `Intro`).
  ),
  // ...
);

Attributes for IntroHighlightDecoration:

Controller

You can control the demo flow through the IntroController instance.

Create a IntroController instance:

You must specify a total number of steps, and other callback events are optional.

IntroController(
  stepCount: 5,
  onWillPrevious: (currentStep) {
    // This callback is called when the demo flow is about to jump to the previous step.
    // You can return `false` if you want to prevent it from taking effect.
  },
  onWillNext: (currentStep) {
    // This callback is called when the demo flow is about to jump to the next step.
    // You can return `false` if you want to prevent it from taking effect.
  },
  onWillClose: (currentStep) {
    // This callback is called when the demo flow is about to close.
    // You can return `false` if you want to prevent it from taking effect.
  },
);

Get the instance:

You can define the controller instance as a global variable to make it easier to use throughout your program. Or, you can get the controller instance through Intro.of(context).controller.

final controller = Intro.of(context).controller;

Get total number of steps:

controller.stepCount;

Get current status:

controller.isOpened;

Start, close and destroy:

Start this demo flow.

controller.start(context);

You can specify a initial step through initStep parameter.

controller.start(context, initStep: 3);

Stop this demo flow.

controller.close();

Destroy this demo flow. Note that it can never be used again when it destroyed.

controller.dispose();

Jump step:

Jump to next step. It's equivalent to close() if called at the last step.

controller.next();

Jump back previous step.

controller.previous();

Jump to specific step.

controller.jumpTo(5);

Manually refresh.

controller.refresh();

Customized intro card

If you don't like the default intro card style, you can customize it through IntroStepTarget.custom constructor.

IntroStepTarget.custom(
  step: step,
  controller: controller,
  cardDecoration: IntroCardDecoration(...),
  cardBuilder: (BuildContext context, IntroParams params, IntroCardDecoration decoration) {
    // Build your card widget.
    // You can use the `params` to get more information or to implement more functionality.
    // You can also use the `decoration` to decorate your card widget. It was defined above or by `Intro` widget.
    return ...;
  },
  child: child,
);

Attributes for IntroParams:

Event-handling

You can do something (such as open a page, pop a dialog, update widget, load resources etc.) at the right time.

• There are five event-handling callbacks are provided.
• They are defined in the IntroStepTarget widget.
• These callbacks can be synchronous or asynchronous.

IntroStepTarget(
  onTargetLoad: () {
    // It will be called when the target widget was built.
  },
  onTargetDispose: () {
    // It will be called when the target widget was disposed.
  },
  onHighlightTap: () {
    // It will be called when tap the highlighted widget.
  },
  onStepWillActivate: (int fromStep) {
    // It will be called when the demo flow reaches the current step.
    // The current step is finally activated only when this callback execution is complete.
    // The `fromStep` tells you from which step it jumped to the current step.
    // In particular, the value of `fromStep` is '0' means that this is the beginning.
  },
  onStepWillDeactivate: (int willToStep) {
    // It will be called when the demo flow leaves the current step.
    // The current step is finally deactivated only when this callback execution is complete.
    // The `willToStep` tells you which step it will to jump to.
    // In particular, the value of `willToStep` is '0' means that this is the ending.
  },
  // ...
);

Nested

You can have multiple demo flows in your program. The same target widget may be used in different demo flow.

Step:

1. Define each controller.

   In this case, you may not be able to get the IntroController exactly from Intro.of(context).controller. So, it's a good idea to save each controller separately beforehand.

final controller1 = IntroController(stepCount: 5);
final controller2 = IntroController(stepCount: 3);

2. Register echoIntro widget. Each one uses a separate controller.

Intro(
  controller: controller1,
  child: Intro(
    controller: controller2,
    child: MyApp(),
  ),
);

3. Bind the step target widgets for each demo flow separately.

   If a target widget is used by multiple demo flow simultaneously, it can be nested build with two IntroStepTarget.

IntroStepTarget(
  controller: controller1,
  step: 1,
  // ...
  child: IntroStepTarget(
    controller: controller2,
    step: 3,
    // ...
    child: targetChild,
  ),
);

4. Perform operations on each controller individually.

Top Layer

The topLayerBuilder of Intro is provided for you to create custom widgets at the top layer. For example, you can build a global exit button.

Intro(
  topLayerBuilder: (context, controller) {
    return Padding(
      padding: const EdgeInsets.only(top: 20, left: 20),
      child: TextButton(
        onPressed: controller.close,
        child: const Text("Exit"),
      ),
    );
  },
  // ...
);

Other

Change barrier color or animation duration.

Intro(
  barrierColor: Colors.black87,
  animationDuration: Duration(milliseconds: 500),
  // ...
);

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To see the full demonstration or more advanced features, read the example code please.