domod

A lightweight data-binding (or so-called mvvm) library, providing both declarative template and imperative call ways.

"domod" is named from "DOM", "Model" and their two-way relationship.

Philosophy

• Connection, relation, dependency. No matter it is data or dom, it is a tree. Tree and tree node relations make up graphs.
• Reactive programming.

Simple Application

A simple application:

const state = {
    count: 0,
    increase() {
        this.count++ // `this` points to `state`
    }
}

DMD.relate(state, {
    negative: {
        resultFrom() {
            return this.count < 0 // `this` points to `state`
        }
    }
})

const view = `
    <div>
        <h1 m-style="{ color: $negative ? 'red' : 'green' }">{{$count}}</h1>
        <button m-onclick="$count = $count - 1">-</button>
        <button m-onclick="$increase()">+</button>
    </div>
`

DMD('#app', view, state)

API

An online demo.

An example of a form:

<script src="path/to/domod.js" charset="utf-8"></script>

<form id="form1">
    <div>
        <label>gender:</label>
        <input m-onclick="$form.gender = 'male'" 
               type="radio" name="gender" value="male" m-checked="$form.gender === 'male'">Male
        <input m-onclick="$form.gender = 'female'" 
               type="radio" name="gender" value="female" m-checked="$form.gender === 'female'">Female
    </div>
    <div>
        <label>mobile:</label>
        <input type="text" name="mobile" m-value="$form.mobile">
        <span m-style="{ display: !!$form.mobile ? 'inline' : 'none' }">
            You input: {{$parse($form.mobile)}}.
        </span>
        <span m-class="['some-class', { red: !$mobileInputStatus }]" 
              m-style="{ display: !$mobileInputStatus ? 'inline' : 'none' }">
            {{$form.mobile}} is {{$mobileInputStatus}}!
        </span>
    </div>
    <div>
        <label>age:</label>
        <select name="age" m-value="$form.age.value">
            <option m-each="$val in $form.age.options" m-value="$val">{{$val}}</option>
        </select>
    </div>
    <div>
        <label>city:</label>
        <select name="city" m-value="$form.city.value">
            <option m-each="($val, $key) in $form.city.options" m-value="$key">
                {{$val.code}}.{{$val.name}}
            </option>
        </select>
    </div>
</form>

<script>
    var store = {
        parse: function (v) {
            return parseInt(v);
        },
        validateMobile: function () {
            return /^1[3|4|5|8][0-9]\d{8}$/.test(this.form.mobile);
        },
        form: {
            gender: 'female',
            mobile: '15210001000',
            age: {
                value: '37-54',
                options: [
                    '0-18',
                    '19-36',
                    '37-54',
                    '55-200'
                ]
            },
            city: {
                value: '1',
                options: [
                    { code: 1, name: 'beijing' },
                    { code: 2, name: 'newyork' },
                    { code: 3, name: 'tokyo' },
                    { code: 4, name: 'london' },
                    { code: 5, name: 'paris' }
                ]
            }
        }
    };

    /* Watch a property mutation */
    store.mobileInputStatus = store.validateMobile();
    DMD.relate(store, {
        'form.mobile': {
            dnstream: 'mobileInputStatus',
            resultIn: function (v) {
                var newVal = store.validateMobile();
                console.log(`mobile is ${newVal}`);
                DMD.$(store, 'mobileInputStatus', newVal);
            }
        }
    });

    DMD('#form1', store);
</script>

Advance

Imperative Calling

Providing a data object:

var store = {
    value: '1'
};

Now assign a property color which would be computed from the property value.

There are two methods available, kernel and relate.

The kernel method, which is actually a constructor function, accepts two parameters besides the data object: the property and its relation object.

new domod.kernel(store, 'color', {
    resultFrom: function () {
        return isNaN(parseInt(store.value)) ? 'red' : 'green';
    }
});

The relate method, which is somehow a composition of kernel, accepts one parameter besides the data object: an object representing a map from property names to relation objects.

domod.relate(store, {
    color: {
        resultFrom: function () {
            return isNaN(parseInt(store.value)) ? 'red' : 'green';
        }
    }
});

Relation Object

A relation object can be declared with these properties:

Property	Effect
resultFrom	Do when the property is being got, and return the value computed.
resultIn	Do when the property is being set.
upstream	Other properties as the property's dependencies.
dnstream	Other properties as the property's effects.

Standalone Libraries

Kernel

See the code and doc for more.

ObservableArray

Also called OArray for short. See the code and doc for more.

License

MIT