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<ol class="chapter"><li class="chapter-item expanded "><a href="introduction.html"><strong aria-hidden="true">1.</strong> Introduction</a></li><li class="chapter-item expanded "><a href="getting_started.html"><strong aria-hidden="true">2.</strong> Getting Started</a></li><li class="chapter-item expanded "><a href="memory_tile.html"><strong aria-hidden="true">3.</strong> Memory Tile</a></li><li class="chapter-item expanded "><a href="polishing_the_tile.html" class="active"><strong aria-hidden="true">4.</strong> Polishing the Tile</a></li><li class="chapter-item expanded "><a href="from_one_to_multiple_tiles.html"><strong aria-hidden="true">5.</strong> From One To Multiple Tiles</a></li><li class="chapter-item expanded "><a href="creating_the_tiles_from_js.html"><strong aria-hidden="true">6.</strong> Creating The Tiles From JavaScript</a></li><li class="chapter-item expanded "><a href="game_logic_in_js.html"><strong aria-hidden="true">7.</strong> Game Logic In JavaScript</a></li><li class="chapter-item expanded "><a href="ideas_for_the_reader.html"><strong aria-hidden="true">8.</strong> Ideas For The Reader</a></li><li class="chapter-item expanded "><a href="conclusion.html"><strong aria-hidden="true">9.</strong> Conclusion</a></li></ol>
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<h1 class="menu-title">Slint Memory Game Tutorial (node)</h1>
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<h1 id="polishing-the-tile"><a class="header" href="#polishing-the-tile">Polishing the Tile</a></h1>
<p>Next, let's add a curtain like cover that opens up when clicking. We achieve this by declaring two rectangles
below the <span class="hljs-built_in">Image</span>, so that they are drawn afterwards and thus on top of the image.
The <span class="hljs-built_in">TouchArea</span> element declares a transparent rectangular region that allows
reacting to user input such as a mouse click or tap. We use that to forward a callback to the <em>MainWindow</em>
that the tile was clicked on. In the <em>MainWindow</em> we react by flipping a custom <em>open_curtain</em> property.
That in turn is used in property bindings for the animated width and x properties. Let's look at the two states a bit
more in detail:</p>
<div class="table-wrapper"><table><thead><tr><th><em>open_curtain</em> value:</th><th>false</th><th>true</th></tr></thead><tbody>
<tr><td>Left curtain rectangle</td><td>Fill the left half by setting the width <em>width</em> to half the parent's width</td><td>Width of zero makes the rectangle invisible</td></tr>
<tr><td>Right curtain rectangle</td><td>Fill the right half by setting <em>x</em> and <em>width</em> to half of the parent's width</td><td><em>width</em> of zero makes the rectangle invisible. <em>x</em> is moved to the right, to slide the curtain open when animated</td></tr>
</tbody></table>
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<p>In order to make our tile extensible, the hard-coded icon name is replaced with an <em>icon</em>
property that can be set from the outside when instantiating the element. For the final polish, we add a
<em>solved</em> property that we use to animate the color to a shade of green when we've found a pair, later. We
replace the code inside the <code>memory.slint</code> file with the following:</p>
<pre><code class="language-slint">component MemoryTile inherits Rectangle {
callback clicked;
in property <bool> open_curtain;
in property <bool> solved;
in property <image> icon;
height: 64px;
width: 64px;
background: solved ? #34CE57 : #3960D5;
animate background { duration: 800ms; }
Image {
source: icon;
width: parent.width;
height: parent.height;
}
// Left curtain
Rectangle {
background: #193076;
x: 0px;
width: open_curtain ? 0px : (parent.width / 2);
height: parent.height;
animate width { duration: 250ms; easing: ease-in; }
}
// Right curtain
Rectangle {
background: #193076;
x: open_curtain ? parent.width : (parent.width / 2);
width: open_curtain ? 0px : (parent.width / 2);
height: parent.height;
animate width { duration: 250ms; easing: ease-in; }
animate x { duration: 250ms; easing: ease-in; }
}
TouchArea {
clicked => {
// Delegate to the user of this element
root.clicked();
}
}
}
export component MainWindow inherits Window {
MemoryTile {
icon: @image-url("icons/bus.png");
clicked => {
self.open_curtain = !self.open_curtain;
}
}
}
</code></pre>
<p>Note the use of <code>root</code> and <code>self</code> in the code. <code>root</code> refers to the outermost
element in the component, that's the <span class="hljs-title">MemoryTile</span> in this case. <code>self</code> refers
to the current element.</p>
<p>Running this gives us a window on the screen with a rectangle that opens up to show us the bus icon, when clicking on
it. Subsequent clicks will close and open the curtain again.</p>
<p><video autoplay loop muted playsinline src="https://slint.dev/blog/memory-game-tutorial/polishing-the-tile.mp4"></video></p>
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