updated docs

Author: Vlad Balin

README.md

@@ -209,3 +209,5 @@ attributes : {
 ```
 It can be accessed as a part of state, however, `link.requestChanges` will be call on assignment
 instead of state modification. Its value will be updated automatically when component will receive new props.
+
+[Guide to Data Binding Use Cases](/example/databinding.md)

example/databinding.md

@@ -0,0 +1,207 @@
+# Data binding examples
+
+Here are the set of examples for typical `nestedreact` data binding use cases.
+
+## Checkboxes
+
+Standard `<input/>` will work. Custom Checkbox component might be implemented like this:
+
+```javascript
+const Checkbox = ({ className = 'checkbox', checkedLink }) => (
+    <div className={ className + ( checkedLink.val() ? ' selected' : '' ) }
+         onClick = { checkedLink.update( x => !x ) }
+    />
+);
+```
+
+Examples will assume working with custom Checkbox.
+
+### Binding to boolean model attributes
+
+```javascript
+import { Model } from 'nestedtypes'
+
+const MyModel = Model
+    .defaults({
+        option1 : true,
+        option2 : false
+    });
+    
+const CheckboxGroup = ({ model /* instanceof MyModel */ }) => (
+    <div>
+        <div>
+            <Checkbox checkedLink={ model.getLink( 'option1' ) } />
+            Option 1
+        </div>
+        <div>
+            <Checkbox checkedLink={ model.getLink( 'option2' ) } />
+            Option 2
+        </div>
+    </div>
+);
+```
+
+### Binding to array of selected options
+
+```javascript
+import { Model } from 'nestedtypes'
+
+const MyModel = Model
+    .defaults({
+        options : [ 'option1' ]
+    });
+    
+const CheckboxGroup = ({ model /* instanceof MyModel */ }) => {
+    const link = model.getLink( 'options' );
+    
+    return (
+        <div>
+            <div>
+                <Checkbox checkedLink={ link.contains( 'option1' ) } />
+                Option 1
+            </div>
+            <div>
+                <Checkbox checkedLink={ link.contains( 'option2' ) } />
+                Option 2
+            </div>
+        </div>
+    );
+};
+```
+
+### Binding to collection of selected models
+
+```javascript
+import { Model } from 'nestedtypes'
+
+const MyModel = Model
+    .defaults({
+        all : Some.Collection,
+        selected : Collection.subsetOf( 'all' )
+    });
+    
+const CheckboxGroup = ({ model /* instanceof MyModel */ }) => {
+    const { all, selected } = model;
+    
+    return (
+        <div>
+            { all.map( model => (
+                <div>
+                    <Checkbox checkedLink={ selected.getLink( model ) } />
+                    { model.displayName }
+                </div>
+            ))}
+        </div>
+    );
+};
+```
+
+## Radio Groups
+
+For the radio groups you will need custom Radio component. It's very similar to custom Checkbox one,
+with one difference in click handler:
+
+```javascript
+const Radio = ({ className = 'radio', checkedLink }) => (
+    <div className={ className + ( checkedLink.val() ? ' selected' : '' ) }
+         onClick = { checkedLink.update( () => true ) }
+    />
+);
+```
+
+In this example, we bind radio to string values. It's not required for them to be strings.
+
+```javascript
+import { Model } from 'nestedtypes'
+
+const MyModel = Model
+    .defaults({
+        option : 'option1'
+    });
+    
+const RadioGroup = ({ model /* instanceof MyModel */ }) => {
+    const link = model.getLink( 'option' );
+    
+    return (
+        <div>
+            <div>
+                <Radio checkedLink={ link.equals( 'option1' ) } />
+                Option 1
+            </div>
+            <div>
+                <Radio checkedLink={ link.equals( 'option2' ) } />
+                Option 2
+            </div>
+        </div>
+    );
+};
+```
+
+## Input fields
+
+Standard `<input>` will work. You may implement custom input controls to handle complex scenarios
+with validation and appearance.
+
+```javascript
+const Input = ({ valueLink, ...props }) => (
+    <div className='wrapping'
+        <input {...props} value={ valueLink.val() } onChange={ e => valueLink.val( e.target.value ) }/>
+    </div>
+);
+```
+
+### Binding to model attributes
+
+```javascript
+import { Model } from 'nestedtypes'
+
+const MyModel = Model
+    .defaults({
+        number : 0,
+        string : ''
+    });
+    
+const InputGroup = ({ model /* instanceof MyModel */ }) => (
+        <div>
+            <label>
+                Number: 
+                <input type='number' valueLink={ model.getLink( 'number' ) } />
+            </label>
+            <label>
+                String: 
+                <input valueLink={ model.getLink( 'string' ) } />
+            </label>
+        </div>
+    );
+};
+```
+
+### Binding to an array of strings
+
+The same technique may be used to bind to an array or hash of strings. First, take a link to this
+attribute. Next, use `link.map` method to iterate through elements links created for you.
+
+`link.map` will internally execute `link.at( key )` method to create a link to the plain object or array element.
+These methods may be used manually to create binding for the structures of any particular depth and complexity.
+
+However, for the JS data with known structure it's recommended to wrap them in models.
+
+```javascript
+import { Model } from 'nestedtypes'
+
+const MyModel = Model
+    .defaults({
+        strings : [ 'first', 'second' ]
+    });
+    
+const InputGroup = ({ model /* instanceof MyModel */ }) => (
+        <div>
+            { model.getLink( 'strings' ).map( strLink => (
+                <div>
+                    <input type='number' valueLink={ strLink } />
+                </div>
+            )) }
+        </div>
+    );
+};
+```