Methods

Methods

Helpers are can define instance methods which can then be called at any time during the lifecycle of the app.


Class methods

Find a helper

Use the findOne class method to find an instance of a helper. You can provide a predicate to look for a specific helper on the screen:

var instance = Fliplet.Helper.findOne({
  name: 'profile',
  fields: { name: 'john' }
});

Find a list of helpers

Use the find class method to find a list of helper instances on a screen. You can provide a predicate to filter for specific helpers:

var instances = Fliplet.Helper.find({
  name: 'profile'
});

Instance methods

Update fields

Use the set instance method to update fields and values at runtime. Given the following example:

var profile;

Fliplet.Helper({
  name: 'profile',
  data: {
    firstName: 'John'
  },
  render: {
    ready: function () {
      profile = this;
    }
  }
});

See how the firstName property can be updated at anytime using a static value or using the result of a promise returned by a function:

profile.set('firstName', 'Nick');

profile.set('firstName', function () {
  return Promise.resolve('Tony');
})

Find all nested helpers

Use the find method to retrieve a list of all helpers nested in the current helper.

<fl-helper name="quiz">
  <fl-helper name="results"></fl-helper>
</fl-helper>
// Get a list of nested helpers by name
var foundHelpers = quiz.find({ name: 'results' });

// You can also use the shorthand
var foundHelpers = quiz.find('results');

// You can also provide a predicate function
var foundHelpers = quiz.find(function (instance) {
  return instance.name === 'results';
});

Find a nested helper

<fl-helper name="quiz">
  <fl-helper name="results"></fl-helper>
</fl-helper>

Use the findOne method to retrieve a helper nested in the current helper.

// Get a nested helper by name
var helperInstance = quiz.findOne({ name: 'results' });

// You can also use the shorthand
var helperInstance = quiz.findOne('results');

// You can also provide a predicate function
var helperInstance = quiz.findOne(function (instance) {
  return instance.name === 'results';
});

Find all children helpers

<fl-helper name="quiz">
  <fl-helper name="results"></fl-helper>
</fl-helper>

Use the children method to retrieve a list of all direct child helpers nested in the current helper.

// Get a list of direct child helpers by name
var foundHelpers = quiz.children({ name: 'results' });

// You can also use the shorthand
var foundHelpers = quiz.children('results');

// You can also provide a predicate function
var foundHelpers = quiz.children(function (instance) {
  return instance.name === 'results';
});

Define new instance methods

Instance methods can be defined via the methods property as shown in the example below:

Fliplet.Helper({
  name: 'welcome',
  render: {
    methods: {
      greet: function () {
        console.log('Hello');
      }
    },
    ready: function () {
      // Greet once a button inside this helper is clickd
      this.$el.find('button').click(this.greet);
    }
  }
});

You can also keep a reference to a helper instance and call its methods any time:

var welcome;

Fliplet.Helper({
  name: 'welcome',
  render: {
    methods: {
      greet: function () {
        console.log('Hello');
      }
    },
    ready: function () {
      welcome = this;
    }
  }
});

welcome.greet();

Further reading

Next article in this series

Fields

Learn more about defining fields in your helpers.