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Breadcrumbs go here --> <li><a href="qdeclarativeelements.html">QML Elements</a></li> <li>QML SpringAnimation Element</li> </ul> </div> <div class="toolbuttons toolblock"> <ul> <li id="smallA" class="t_button">A</li> <li id="medA" class="t_button active">A</li> <li id="bigA" class="t_button">A</li> <li id="print" class="t_button"><a href="javascript:this.print();"> <span>Print</span></a></li> </ul> </div> </div> <div class="content mainContent"> <p class="naviNextPrevious headerNavi"> </p><p/> <div class="toc"> <h3><a name="toc">Contents</a></h3> <ul> <li class="level1"><a href="#properties">Properties</a></li> <li class="level1"><a href="#details">Detailed Description</a></li> </ul> </div> <h1 class="title">QML SpringAnimation Element</h1> <span class="subtitle"></span> <!-- $$$SpringAnimation-brief --> <p>The SpringAnimation element allows a property to track a value in a spring-like motion. <a href="#details">More...</a></p> <!-- @@@SpringAnimation --> <p>Inherits <a href="qml-numberanimation.html">NumberAnimation</a></p> <p>This element was introduced in Qt 4.7.</p> <ul> <li><a href="qml-springanimation-members.html">List of all members, including inherited members</a></li> </ul> <a name="properties"></a> <h2>Properties</h2> <ul> <li class="fn"><b><b><a href="qml-springanimation.html#damping-prop">damping</a></b></b> : real</li> <li class="fn"><b><b><a href="qml-springanimation.html#epsilon-prop">epsilon</a></b></b> : real</li> <li class="fn"><b><b><a href="qml-springanimation.html#mass-prop">mass</a></b></b> : real</li> <li class="fn"><b><b><a href="qml-springanimation.html#modulus-prop">modulus</a></b></b> : real</li> <li class="fn"><b><b><a href="qml-springanimation.html#spring-prop">spring</a></b></b> : real</li> <li class="fn"><b><b><a href="qml-springanimation.html#velocity-prop">velocity</a></b></b> : real</li> </ul> <!-- $$$SpringAnimation-description --> <a name="details"></a> <h2>Detailed Description</h2> <p>SpringAnimation mimics the oscillatory behavior of a spring, with the appropriate <a href="qml-springanimation.html#spring-prop">spring</a> constant to control the acceleration and the <a href="qml-springanimation.html#damping-prop">damping</a> to control how quickly the effect dies away.</p> <p>You can also limit the maximum <a href="qml-springanimation.html#velocity-prop">velocity</a> of the animation.</p> <p>The following <a href="qml-rectangle.html">Rectangle</a> moves to the position of the mouse using a SpringAnimation when the mouse is clicked. The use of the <a href="qml-behavior.html">Behavior</a> on the <tt>x</tt> and <tt>y</tt> values indicates that whenever these values are changed, a SpringAnimation should be applied.</p> <pre class="qml"> import QtQuick 1.0 <span class="type"><a href="qml-item.html">Item</a></span> { <span class="name">width</span>: <span class="number">300</span>; <span class="name">height</span>: <span class="number">300</span> <span class="type"><a href="qml-rectangle.html">Rectangle</a></span> { <span class="name">id</span>: <span class="name">rect</span> <span class="name">width</span>: <span class="number">50</span>; <span class="name">height</span>: <span class="number">50</span> <span class="name">color</span>: <span class="string">"red"</span> Behavior on <span class="name">x</span> { <span class="type">SpringAnimation</span> { <span class="name">spring</span>: <span class="number">2</span>; <span class="name">damping</span>: <span class="number">0.2</span> } } Behavior on <span class="name">y</span> { <span class="type">SpringAnimation</span> { <span class="name">spring</span>: <span class="number">2</span>; <span class="name">damping</span>: <span class="number">0.2</span> } } } <span class="type"><a href="qml-mousearea.html">MouseArea</a></span> { <span class="name">anchors</span>.fill: <span class="name">parent</span> <span class="name">onClicked</span>: { <span class="name">rect</span>.<span class="name">x</span> <span class="operator">=</span> <span class="name">mouse</span>.<span class="name">x</span> <span class="operator">-</span> <span class="name">rect</span>.<span class="name">width</span><span class="operator">/</span><span class="number">2</span> <span class="name">rect</span>.<span class="name">y</span> <span class="operator">=</span> <span class="name">mouse</span>.<span class="name">y</span> <span class="operator">-</span> <span class="name">rect</span>.<span class="name">height</span><span class="operator">/</span><span class="number">2</span> } } }</pre> <p>Like any other animation element, a SpringAnimation can be applied in a number of ways, including transitions, behaviors and property value sources. The <a href="qdeclarativeanimation.html">QML Animation and Transitions</a> documentation shows a variety of methods for creating animations.</p> <p><b>See also </b><a href="qml-smoothedanimation.html">SmoothedAnimation</a>, <a href="qdeclarativeanimation.html">QML Animation and Transitions</a>, Animation basics example, and <a href="declarative-toys-clocks.html">Clocks example</a>.</p> <!-- @@@SpringAnimation --> <h2>Property Documentation</h2> <!-- $$$damping --> <div class="qmlitem"><div class="qmlproto"><table class="qmlname"><tr valign="top" class="odd"><td class="tblQmlPropNode"><p><a name="damping-prop"></a><span class="name">damping</span> : <span class="type"><a href="qml-real.html">real</a></span></p></td></tr></table></div><div class="qmldoc"><p>This property holds the spring damping value.</p> <p>This value describes how quickly the spring-like motion comes to rest. The default value is 0.</p> <p>The useful value range is 0 - 1.0. The lower the value, the faster it comes to rest.</p> </div></div><!-- @@@damping --> <br/> <!-- $$$epsilon --> <div class="qmlitem"><div class="qmlproto"><table class="qmlname"><tr valign="top" class="odd"><td class="tblQmlPropNode"><p><a name="epsilon-prop"></a><span class="name">epsilon</span> : <span class="type"><a href="qml-real.html">real</a></span></p></td></tr></table></div><div class="qmldoc"><p>This property holds the spring epsilon.</p> <p>The epsilon is the rate and amount of change in the value which is close enough to 0 to be considered equal to zero. This will depend on the usage of the value. For pixel positions, 0.25 would suffice. For scale, 0.005 will suffice.</p> <p>The default is 0.01. Tuning this value can provide small performance improvements.</p> </div></div><!-- @@@epsilon --> <br/> <!-- $$$mass --> <div class="qmlitem"><div class="qmlproto"><table class="qmlname"><tr valign="top" class="odd"><td class="tblQmlPropNode"><p><a name="mass-prop"></a><span class="name">mass</span> : <span class="type"><a href="qml-real.html">real</a></span></p></td></tr></table></div><div class="qmldoc"><p>This property holds the "mass" of the property being moved.</p> <p>The value is 1.0 by default.</p> <p>A greater mass causes slower movement and a greater spring-like motion when an item comes to rest.</p> </div></div><!-- @@@mass --> <br/> <!-- $$$modulus --> <div class="qmlitem"><div class="qmlproto"><table class="qmlname"><tr valign="top" class="odd"><td class="tblQmlPropNode"><p><a name="modulus-prop"></a><span class="name">modulus</span> : <span class="type"><a href="qml-real.html">real</a></span></p></td></tr></table></div><div class="qmldoc"><p>This property holds the modulus value. The default value is 0.</p> <p>Setting a <i>modulus</i> forces the target value to "wrap around" at the modulus. For example, setting the modulus to 360 will cause a value of 370 to wrap around to 10.</p> </div></div><!-- @@@modulus --> <br/> <!-- $$$spring --> <div class="qmlitem"><div class="qmlproto"><table class="qmlname"><tr valign="top" class="odd"><td class="tblQmlPropNode"><p><a name="spring-prop"></a><span class="name">spring</span> : <span class="type"><a href="qml-real.html">real</a></span></p></td></tr></table></div><div class="qmldoc"><p>This property describes how strongly the target is pulled towards the source. The default value is 0 (that is, the spring-like motion is disabled).</p> <p>The useful value range is 0 - 5.0.</p> <p>When this property is set and the <a href="qml-springanimation.html#velocity-prop">velocity</a> value is greater than 0, the <a href="qml-springanimation.html#velocity-prop">velocity</a> limits the maximum speed.</p> </div></div><!-- @@@spring --> <br/> <!-- $$$velocity --> <div class="qmlitem"><div class="qmlproto"><table class="qmlname"><tr valign="top" class="odd"><td class="tblQmlPropNode"><p><a name="velocity-prop"></a><span class="name">velocity</span> : <span class="type"><a href="qml-real.html">real</a></span></p></td></tr></table></div><div class="qmldoc"><p>This property holds the maximum velocity allowed when tracking the source.</p> <p>The default value is 0 (no maximum velocity).</p> </div></div><!-- @@@velocity --> <br/> <p class="naviNextPrevious footerNavi"> </p> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2013 Digia Plc and/or its subsidiaries. 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