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POTemporarily breaking/pausing an Ember.Binding
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copied!<p>I'm trying to figure out how to write <code>pauseBinding()</code> and <code>resumeBinding()</code>, so that I can interrupt bindings between application layers, e.g. if a validation fails on user input into an Ember.TextField.</p> <pre><code>var source = Ember.Object.create({ value: 10 }); var target = Ember.Object.extend({ source: source, valueBinding: 'source.value' }); console.log(source.get('value'), target.get('value')); // 10, 10 target.set('value', 20); console.log(source.get('value'), target.get('value')); // 20, 20 // Stop synchronizing between target.value and source.value pauseBinding(target.get('valueBinding')); // Only update target.value target.set('value', 40); console.log(source.get('value'), target.get('value')); // 20, 40 // Resume synchronizing, target.value is overwritten resumeBinding(target.get('valueBinding')); console.log(source.get('value'), target.get('value')); // 20, 20 </code></pre> <p>Or, asking this more generally: <strong>what is the most proper idiom for creating conditional bindings</strong>, bindings that flow only-one-way, only-the-other-one-way, both-ways, or no-ways depending on a condition (another property) ?</p> <p>A condition might be a validation (if validation fails, don't spread the invalid value further), or a condition might be in response to UI state such as focus (if the control is focused, don't programmatically update its value, as this will confuse the UI).</p> <p>For example, when an Ember.TextField with a valueBinding is focused (as in, active user input), I don't want it being updated, even if the to() side of the binding updates. But this seems like a oneWay() binding that's the <em>opposite</em> direction (oneWay from -> to, instead of oneWay to -> from).</p>

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