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The constructor function is initialized with values specified by the component element's data bindings.">ViewModel</a> values from the user content.</li> </ul> <p>The default value is <code>false</code>.</p> <p>To change leakScope from the default</p> <pre><code class="language-js">Component.extend({ tag: "my-component", leakScope: true, ViewModel: { message: "Hello World!" }, view: stache("{{message}}") }) </code></pre> <p>Leaving <code>leakScope</code> as the default <code>false</code> is useful for hiding and protecting internal details of <code>Component</code>, potentially preventing accidental clashes. It can be helpful to set it to <code>true</code> if you, for example, wanted to customize <strong>user content</strong> based on some value in the component's ViewModel.</p> </div> <section class="body"> <h2>Use</h2> <p>A component's <a href="can-component.prototype.leakScope.html" title="Allow reading the outer scope values from a component's template and a component's viewModel values in the user content.">leakScope</a> option controls if a component's template can access the component's outer scope and the user content can read the component's view model.</p> <p>Lets define what <strong>outer scope</strong>, <strong>component's template</strong> and <strong>user content</strong> mean.</p> <p>If I have a <code><hello-world></code> component in a template like:</p> <pre><code>{{#data}} <hello-world>{{subject}}</hello-world> {{/data}} </code></pre> <p>The <strong>outer scope</strong> of <code><hello-world></code> has <code>data</code> as its context. The <strong>user content</strong> of <code><hello-world></code> is the template between its tags. In this case, the <strong>user content</strong> is <code>{{subject}}</code>.</p> <p>Finally, if <code><hello-world></code> is defined like:</p> <pre><code>Component.extend({ tag: "hello-world", view: stache("{{greeting}} <content/>{{exclamation}}") }) </code></pre> <p><code>{{greeting}} <content/>{{exclamation}}</code> represents the <strong>component's template</strong>.</p> <h2>Using outer scope in component template</h2> <p>If <code>leakScope</code> is <code>true</code>, the <strong>component's template</strong> can read the data in the outer scope and will see <code>name: "John"</code> overwriting <code>name: "World"</code> in the component's viewModel instance in the following example.</p> <p>If the following component is defined:</p> <pre><code class="language-js">Component.extend({ tag: 'hello-world', leakScope: true, // changed to true instead of the default value ViewModel: {name: "World"}, view: stache("Hello {{name}}") }); </code></pre> <p>With this data in the outer scope:</p> <pre><code class="language-js">{ name: "John" } </code></pre> <p>And used like so:</p> <pre><code><hello-world /> </code></pre> <p>If <code>leakScope</code> is <code>true</code> it will render:</p> <pre><code><hello-world>Hello John</hello-world> </code></pre> <p>If <code>leakScope</code> is <code>false</code> it will render:</p> <pre><code><hello-world>Hello World</hello-world> </code></pre> <h2>Using viewModel in user content</h2> <p>if <code>leakScope</code> is <code>true</code>, the <strong>user content</strong> is able to see the name property on the component's viewModel instance in the following example. Else, name won't be seen.</p> <p>If the following component is defined:</p> <pre><code class="language-js">Component.extend({ tag: 'hello-world', leakScope: true, // changed to true instead of the default value ViewModel: {name: "World"}, view: stache("Hello <content />") }); </code></pre> <p>And used like so:</p> <pre><code><hello-world>{{name}}</hello-world> </code></pre> <p>If <code>leakScope</code> is <code>true</code> it will render:</p> <pre><code><hello-world>Hello World</hello-world> </code></pre> <p>If <code>leakScope</code> is <code>false</code> it will render:</p> <pre><code><hello-world>Hello </hello-world> </code></pre> </section> <script type="text/javascript"> var docObject = {"src":{"path":"node_modules/can-component/docs/leakscope.md"},"description":"Allow reading the outer scope values from a component's template and a component's viewModel values in the user content.\n\n","types":[{"type":"Boolean","description":"`false` limits reading to:\n\n- the component's viewModel from the component's template, and\n- the outer scope values from the user content.\n\n`true` adds the ability to read:\n\n- the outer [can-view-scope scope] values from the component's template, and\n- the component's [can-component.prototype.ViewModel] values from the user content.\n\nThe default value is `false`.\n\nTo change leakScope from the default\n```js\nComponent.extend({\n\ttag: \"my-component\",\n\tleakScope: true,\n\tViewModel: { message: \"Hello World!\" },\n\tview: stache(\"{{message}}\")\n})\n```\n\nLeaving `leakScope` as the default `false` is useful for hiding and protecting\ninternal details of `Component`, potentially preventing accidental\nclashes. It can be helpful to set it to `true` if you, for example, wanted to customize __user content__\nbased on some value in the component's ViewModel.\n"}],"title":"leakScope","name":"can-component.prototype.leakScope","type":"property","parent":"can-component.prototype","comment":" ","pathToRoot":".."}; </script> </article> <footer><p>CanJS is part of <a href="http://donejs.com" target="_blank">DoneJS</a>. Created and maintained by the core <a href="https://donejs.com/About.html#section=section_Team" target="_blank">DoneJS team</a> and <a href="http://bitovi.com" target="_blank">Bitovi</a>. <strong>Currently 3.0.0.</strong></p></footer> </div> </div> </div> <script> steal = { instantiated: { "bundles/bit-docs-site/static.css!$css" : null } }; </script> <script type='text/javascript' data-main="bit-docs-site/static" src="./static/node_modules/steal/steal.production.js"></script> <script async defer src="https://buttons.github.io/buttons.js"></script> </body> </html>