<!DOCTYPE html><htmllang="en"><head><metacharset="utf-8"><metaname="viewport"content="width=device-width, initial-scale=1.0"><metaname="generator"content="rustdoc"><metaname="description"content="API documentation for the Rust `WidgetImpl` trait in crate `widgetry`."><metaname="keywords"content="rust, rustlang, rust-lang, WidgetImpl"><title>widgetry::WidgetImpl - Rust</title><linkrel="stylesheet"type="text/css"href="../normalize.css"><linkrel="stylesheet"type="text/css"href="../rustdoc.css"id="mainThemeStyle"><linkrel="stylesheet"type="text/css"href="../light.css"id="themeStyle"><linkrel="stylesheet"type="text/css"href="../dark.css"disabled><linkrel="stylesheet"type="text/css"href="../ayu.css"disabled><scriptsrc="../storage.js"></script><noscript><linkrel="stylesheet"href="../noscript.css"></noscript><linkrel="shortcut icon"href="../favicon.ico"><styletype="text/css">#crate-search{background-image:url("../down-arrow.svg");}</style></head><bodyclass="rustdoc trait"><!--[if lte IE 8]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><navclass="sidebar"><divclass="sidebar-menu">☰</div><ahref='../widgetry/index.html'><divclass='logo-container rust-logo'><imgsrc='../rust-logo.png'alt='logo'></div></a><pclass='location'>Trait WidgetImpl</p><divclass="sidebar-elems"><divclass="block items"><aclass="sidebar-title"href="#required-methods">Required Methods</a><divclass="sidebar-links"><ahref="#tymethod.draw">draw</a><ahref="#tymethod.event">event</a><ahref="#tymethod.get_dims">get_dims</a><ahref="#tymethod.set_pos">set_pos</a></div><aclass="sidebar-title"href="#provided-methods">Provided Methods</a><divclass="sidebar-links"><ahref="#method.can_restore">can_restore</a><ahref="#method.restore">restore</a></div><aclass="sidebar-title"href="#implementations">Methods</a><divclass="sidebar-links"><ahref="#method.downcast">downcast</a><ahref="#method.downcast_mut">downcast_mut</a><ahref="#method.downcast_rc">downcast_rc</a><ahref="#method.downcast_ref">downcast_ref</a><ahref="#method.is">is</a></div><aclass="sidebar-title"href="#implementors">Implementors</a></div><pclass='location'><ahref='index.html'>widgetry</a></p><script>window.sidebarCurrent={name:'WidgetImpl',ty:'trait',relpath:''};</script><scriptdefersrc="sidebar-items.js"></script></div></nav><divclass="theme-picker"><buttonid="theme-picker"aria-label="Pick another theme!"><imgsrc="../brush.svg"width="18"alt="Pick another theme!"></button><divid="theme-choices"></div></div><scriptsrc="../theme.js"></script><navclass="sub"><formclass="search-form"><divclass="search-container"><div><selectid="crate-search"><optionvalue="All crates">All crates</option></select><inputclass="search-input"name="search"disabledautocomplete="off"spellcheck="false"placeholder="Click or press ‘S’ to search, ‘?’ for more options…"type="search"></div><spanclass="help-button">?</span>
}</pre></div><divclass='docblock'><p>Create a new widget by implementing this trait. You can instantiate your widget by calling
<code>Widget::new(Box::new(instance of your new widget))</code>, which gives you the usual style options.</p>
</div>
<h2id='required-methods'class='small-section-header'>Required methods<ahref='#required-methods'class='anchor'></a></h2><divclass='methods'><h3id='tymethod.get_dims'class='method'><code>fn <ahref='#tymethod.get_dims'class='fnname'>get_dims</a>(&self) -><aclass="struct"href="../widgetry/struct.ScreenDims.html"title="struct widgetry::ScreenDims">ScreenDims</a></code></h3><divclass='docblock'><p>What width and height does the widget occupy? If this changes, be sure to set
<code>redo_layout</code> to true in <code>event</code>.</p>
</div><h3id='tymethod.set_pos'class='method'><code>fn <ahref='#tymethod.set_pos'class='fnname'>set_pos</a>(&mut self, top_left: <aclass="struct"href="../widgetry/struct.ScreenPt.html"title="struct widgetry::ScreenPt">ScreenPt</a>)</code></h3><divclass='docblock'><p>Your widget's top left corner should be here. Handle mouse events and draw appropriately.</p>
</div><h3id='tymethod.event'class='method'><code>fn <ahref='#tymethod.event'class='fnname'>event</a>(&mut self, ctx: &mut <aclass="struct"href="../widgetry/struct.EventCtx.html"title="struct widgetry::EventCtx">EventCtx</a><'_>, output: &mut <aclass="struct"href="../widgetry/struct.WidgetOutput.html"title="struct widgetry::WidgetOutput">WidgetOutput</a>)</code></h3><divclass='docblock'><p>Your chance to react to an event. Any side effects outside of this widget are communicated
</div><h3id='tymethod.draw'class='method'><code>fn <ahref='#tymethod.draw'class='fnname'>draw</a>(&self, g: &mut <aclass="struct"href="../widgetry/struct.GfxCtx.html"title="struct widgetry::GfxCtx">GfxCtx</a><'_>)</code></h3><divclass='docblock'><p>Draw the widget. Be sure to draw relative to the top-left specified by <code>set_pos</code>.</p>
<h2id='provided-methods'class='small-section-header'>Provided methods<ahref='#provided-methods'class='anchor'></a></h2><divclass='methods'><h3id='method.can_restore'class='method'><code>fn <ahref='#method.can_restore'class='fnname'>can_restore</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a></code></h3><divclass='docblock'><p>If a new Panel is being created to replace an older one, all widgets have the chance to
</div><h3id='method.restore'class='method'><code>fn <ahref='#method.restore'class='fnname'>restore</a>(&mut self, _: &mut <aclass="struct"href="../widgetry/struct.EventCtx.html"title="struct widgetry::EventCtx">EventCtx</a><'_>, _prev: &<aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/boxed/struct.Box.html"title="struct alloc::boxed::Box">Box</a><dyn <aclass="trait"href="../widgetry/widgets/trait.WidgetImpl.html"title="trait widgetry::widgets::WidgetImpl">WidgetImpl</a>>)</code></h3><divclass='docblock'><p>Restore state from the previous version of this widget, with the same ID. Implementors must
</div></div><spanclass='loading-content'>Loading content...</span><h2id='implementations'class='small-section-header'>Implementations<ahref='#implementations'class='anchor'></a></h2><h3id='impl'class='impl'><codeclass='in-band'>impl dyn <aclass="trait"href="../widgetry/widgets/trait.WidgetImpl.html"title="trait widgetry::widgets::WidgetImpl">WidgetImpl</a></code><ahref='#impl'class='anchor'></a></h3><divclass='impl-items'><h4id='method.is'class="method"><code>pub fn <ahref='#method.is'class='fnname'>is</a><__T: <aclass="trait"href="../widgetry/widgets/trait.WidgetImpl.html"title="trait widgetry::widgets::WidgetImpl">WidgetImpl</a>>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a></code></h4><divclass='docblock'><p>Returns true if the trait object wraps an object of type <code>__T</code>.</p>
</div><h4id='method.downcast'class="method"><code>pub fn <ahref='#method.downcast'class='fnname'>downcast</a><__T: <aclass="trait"href="../widgetry/widgets/trait.WidgetImpl.html"title="trait widgetry::widgets::WidgetImpl">WidgetImpl</a>>(self: <aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/boxed/struct.Box.html"title="struct alloc::boxed::Box">Box</a><Self>) -><aclass="enum"href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html"title="enum core::result::Result">Result</a><<aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/boxed/struct.Box.html"title="struct alloc::boxed::Box">Box</a><__T>, <aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/boxed/struct.Box.html"title="struct alloc::boxed::Box">Box</a><Self>></code></h4><divclass='docblock'><p>Returns a boxed object from a boxed trait object if the underlying object is of type
<code>__T</code>. Returns the original boxed trait if it isn't.</p>
</div><h4id='method.downcast_rc'class="method"><code>pub fn <ahref='#method.downcast_rc'class='fnname'>downcast_rc</a><__T: <aclass="trait"href="../widgetry/widgets/trait.WidgetImpl.html"title="trait widgetry::widgets::WidgetImpl">WidgetImpl</a>>(self: <aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html"title="struct alloc::rc::Rc">Rc</a><Self>) -><aclass="enum"href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html"title="enum core::result::Result">Result</a><<aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html"title="struct alloc::rc::Rc">Rc</a><__T>, <aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html"title="struct alloc::rc::Rc">Rc</a><Self>></code></h4><divclass='docblock'><p>Returns an <code>Rc</code>-ed object from an <code>Rc</code>-ed trait object if the underlying object is of
type <code>__T</code>. Returns the original <code>Rc</code>-ed trait if it isn't.</p>
</div><h4id='method.downcast_ref'class="method"><code>pub fn <ahref='#method.downcast_ref'class='fnname'>downcast_ref</a><__T: <aclass="trait"href="../widgetry/widgets/trait.WidgetImpl.html"title="trait widgetry::widgets::WidgetImpl">WidgetImpl</a>>(&self) -><aclass="enum"href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html"title="enum core::option::Option">Option</a><<aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&</a>__T></code></h4><divclass='docblock'><p>Returns a reference to the object within the trait object if it is of type <code>__T</code>, or
<code>None</code> if it isn't.</p>
</div><h4id='method.downcast_mut'class="method"><code>pub fn <ahref='#method.downcast_mut'class='fnname'>downcast_mut</a><__T: <aclass="trait"href="../widgetry/widgets/trait.WidgetImpl.html"title="trait widgetry::widgets::WidgetImpl">WidgetImpl</a>>(&mut self) -><aclass="enum"href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html"title="enum core::option::Option">Option</a><<aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&mut </a>__T></code></h4><divclass='docblock'><p>Returns a mutable reference to the object within the trait object if it is of type
<code>__T</code>, or <code>None</code> if it isn't.</p>
