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   1 <html><head><title>Roo/util/TextMetrics.js</title><link rel="stylesheet" type="text/css" href="../../css/highlight-js.css"/></head><body class="highlightpage"><code class="jsdoc-pretty"><span class="jsdoc-comment">/*
   2  * Based on:
   3  * Ext JS Library 1.1.1
   4  * Copyright(c) 2006-2007, Ext JS, LLC.
   5  *
   6  * Originally Released Under LGPL - original licence link has changed is not relivant.
   7  *
   8  * Fork - LGPL
   9  * &lt;script type=&quot;text/javascript&quot;&gt;
  10  */
  11
  12
  13 /**
  14  * @class Roo.util.TextMetrics
  15  * Provides precise pixel measurements for blocks of text so that you can determine exactly how high and
  16  * wide, in pixels, a given block of text will be.
  17  * @singleton
  18  */
  19 </span><span class="jsdoc-var">Roo.util.TextMetrics </span><span class="jsdoc-syntax">= </span><span class="jsdoc-keyword">function</span><span class="jsdoc-syntax">(){
  20     </span><span class="jsdoc-keyword">var </span><span class="jsdoc-var">shared</span><span class="jsdoc-syntax">;
  21     </span><span class="jsdoc-keyword">return </span><span class="jsdoc-syntax">{
  22         </span><span class="jsdoc-comment">/**
  23          * Measures the size of the specified text
  24          * @param {String/HTMLElement} el The element, dom node or id from which to copy existing CSS styles
  25          * that can affect the size of the rendered text
  26          * @param {String} text The text to measure
  27          * @param {Number} fixedWidth (optional) If the text will be multiline, you have to set a fixed width
  28          * in order to accurately measure the text height
  29          * @return {Object} An object containing the text's size {width: (width), height: (height)}
  30          */
  31         </span><span class="jsdoc-var">measure </span><span class="jsdoc-syntax">: </span><span class="jsdoc-keyword">function</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">el</span><span class="jsdoc-syntax">, </span><span class="jsdoc-var">text</span><span class="jsdoc-syntax">, </span><span class="jsdoc-var">fixedWidth</span><span class="jsdoc-syntax">){
  32             </span><span class="jsdoc-keyword">if</span><span class="jsdoc-syntax">(!</span><span class="jsdoc-var">shared</span><span class="jsdoc-syntax">){
  33                 </span><span class="jsdoc-var">shared </span><span class="jsdoc-syntax">= </span><span class="jsdoc-var">Roo.util.TextMetrics.Instance</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">el</span><span class="jsdoc-syntax">, </span><span class="jsdoc-var">fixedWidth</span><span class="jsdoc-syntax">);
  34             }
  35             </span><span class="jsdoc-var">shared.bind</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">el</span><span class="jsdoc-syntax">);
  36             </span><span class="jsdoc-var">shared.setFixedWidth</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">fixedWidth </span><span class="jsdoc-syntax">|| </span><span class="jsdoc-string">'auto'</span><span class="jsdoc-syntax">);
  37             </span><span class="jsdoc-keyword">return </span><span class="jsdoc-var">shared.getSize</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">text</span><span class="jsdoc-syntax">);
  38         },
  39
  40         </span><span class="jsdoc-comment">/**
  41          * Return a unique TextMetrics instance that can be bound directly to an element and reused.  This reduces
  42          * the overhead of multiple calls to initialize the style properties on each measurement.
  43          * @param {String/HTMLElement} el The element, dom node or id that the instance will be bound to
  44          * @param {Number} fixedWidth (optional) If the text will be multiline, you have to set a fixed width
  45          * in order to accurately measure the text height
  46          * @return {Roo.util.TextMetrics.Instance} instance The new instance
  47          */
  48         </span><span class="jsdoc-var">createInstance </span><span class="jsdoc-syntax">: </span><span class="jsdoc-keyword">function</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">el</span><span class="jsdoc-syntax">, </span><span class="jsdoc-var">fixedWidth</span><span class="jsdoc-syntax">){
  49             </span><span class="jsdoc-keyword">return </span><span class="jsdoc-var">Roo.util.TextMetrics.Instance</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">el</span><span class="jsdoc-syntax">, </span><span class="jsdoc-var">fixedWidth</span><span class="jsdoc-syntax">);
  50         }
  51     };
  52 }();
  53
  54
  55
  56 </span><span class="jsdoc-var">Roo.util.TextMetrics.Instance </span><span class="jsdoc-syntax">= </span><span class="jsdoc-keyword">function</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">bindTo</span><span class="jsdoc-syntax">, </span><span class="jsdoc-var">fixedWidth</span><span class="jsdoc-syntax">){
  57     </span><span class="jsdoc-keyword">var </span><span class="jsdoc-var">ml </span><span class="jsdoc-syntax">= </span><span class="jsdoc-keyword">new </span><span class="jsdoc-var">Roo.Element</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">document.createElement</span><span class="jsdoc-syntax">(</span><span class="jsdoc-string">'div'</span><span class="jsdoc-syntax">));
  58     </span><span class="jsdoc-var">document.body.appendChild</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">ml.dom</span><span class="jsdoc-syntax">);
  59     </span><span class="jsdoc-var">ml.position</span><span class="jsdoc-syntax">(</span><span class="jsdoc-string">'absolute'</span><span class="jsdoc-syntax">);
  60     </span><span class="jsdoc-var">ml.setLeftTop</span><span class="jsdoc-syntax">(-1000, -1000);
  61     </span><span class="jsdoc-var">ml.hide</span><span class="jsdoc-syntax">();
  62
  63     </span><span class="jsdoc-keyword">if</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">fixedWidth</span><span class="jsdoc-syntax">){
  64         </span><span class="jsdoc-var">ml.setWidth</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">fixedWidth</span><span class="jsdoc-syntax">);
  65     }
  66
  67     </span><span class="jsdoc-keyword">var </span><span class="jsdoc-var">instance </span><span class="jsdoc-syntax">= {
  68         </span><span class="jsdoc-comment">/**
  69          * Returns the size of the specified text based on the internal element's style and width properties
  70          * @memberOf Roo.util.TextMetrics.Instance#
  71          * @param {String} text The text to measure
  72          * @return {Object} An object containing the text's size {width: (width), height: (height)}
  73          */
  74         </span><span class="jsdoc-var">getSize </span><span class="jsdoc-syntax">: </span><span class="jsdoc-keyword">function</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">text</span><span class="jsdoc-syntax">){
  75             </span><span class="jsdoc-var">ml.update</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">text</span><span class="jsdoc-syntax">);
  76             </span><span class="jsdoc-keyword">var </span><span class="jsdoc-var">s </span><span class="jsdoc-syntax">= </span><span class="jsdoc-var">ml.getSize</span><span class="jsdoc-syntax">();
  77             </span><span class="jsdoc-var">ml.update</span><span class="jsdoc-syntax">(</span><span class="jsdoc-string">''</span><span class="jsdoc-syntax">);
  78             </span><span class="jsdoc-keyword">return </span><span class="jsdoc-var">s</span><span class="jsdoc-syntax">;
  79         },
  80
  81         </span><span class="jsdoc-comment">/**
  82          * Binds this TextMetrics instance to an element from which to copy existing CSS styles
  83          * that can affect the size of the rendered text
  84          * @memberOf Roo.util.TextMetrics.Instance#
  85          * @param {String/HTMLElement} el The element, dom node or id
  86          */
  87         </span><span class="jsdoc-var">bind </span><span class="jsdoc-syntax">: </span><span class="jsdoc-keyword">function</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">el</span><span class="jsdoc-syntax">){
  88             </span><span class="jsdoc-var">ml.setStyle</span><span class="jsdoc-syntax">(
  89                 </span><span class="jsdoc-var">Roo.fly</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">el</span><span class="jsdoc-syntax">)</span><span class="jsdoc-var">.getStyles</span><span class="jsdoc-syntax">(</span><span class="jsdoc-string">'font-size'</span><span class="jsdoc-syntax">,</span><span class="jsdoc-string">'font-style'</span><span class="jsdoc-syntax">, </span><span class="jsdoc-string">'font-weight'</span><span class="jsdoc-syntax">, </span><span class="jsdoc-string">'font-family'</span><span class="jsdoc-syntax">,</span><span class="jsdoc-string">'line-height'</span><span class="jsdoc-syntax">)
  90             );
  91         },
  92
  93         </span><span class="jsdoc-comment">/**
  94          * Sets a fixed width on the internal measurement element.  If the text will be multiline, you have
  95          * to set a fixed width in order to accurately measure the text height.
  96          * @memberOf Roo.util.TextMetrics.Instance#
  97          * @param {Number} width The width to set on the element
  98          */
  99         </span><span class="jsdoc-var">setFixedWidth </span><span class="jsdoc-syntax">: </span><span class="jsdoc-keyword">function</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">width</span><span class="jsdoc-syntax">){
 100             </span><span class="jsdoc-var">ml.setWidth</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">width</span><span class="jsdoc-syntax">);
 101         },
 102
 103         </span><span class="jsdoc-comment">/**
 104          * Returns the measured width of the specified text
 105          * @memberOf Roo.util.TextMetrics.Instance#
 106          * @param {String} text The text to measure
 107          * @return {Number} width The width in pixels
 108          */
 109         </span><span class="jsdoc-var">getWidth </span><span class="jsdoc-syntax">: </span><span class="jsdoc-keyword">function</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">text</span><span class="jsdoc-syntax">){
 110             </span><span class="jsdoc-var">ml.dom.style.width </span><span class="jsdoc-syntax">= </span><span class="jsdoc-string">'auto'</span><span class="jsdoc-syntax">;
 111             </span><span class="jsdoc-keyword">return </span><span class="jsdoc-var">this.getSize</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">text</span><span class="jsdoc-syntax">)</span><span class="jsdoc-var">.width</span><span class="jsdoc-syntax">;
 112         },
 113
 114         </span><span class="jsdoc-comment">/**
 115          * Returns the measured height of the specified text.  For multiline text, be sure to call
 116          * {@link #setFixedWidth} if necessary.
 117          * @memberOf Roo.util.TextMetrics.Instance#
 118          * @param {String} text The text to measure
 119          * @return {Number} height The height in pixels
 120          */
 121         </span><span class="jsdoc-var">getHeight </span><span class="jsdoc-syntax">: </span><span class="jsdoc-keyword">function</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">text</span><span class="jsdoc-syntax">){
 122             </span><span class="jsdoc-keyword">return </span><span class="jsdoc-var">this.getSize</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">text</span><span class="jsdoc-syntax">)</span><span class="jsdoc-var">.height</span><span class="jsdoc-syntax">;
 123         }
 124     };
 125
 126     </span><span class="jsdoc-var">instance.bind</span><span class="jsdoc-syntax">(</span><span class="jsdoc-var">bindTo</span><span class="jsdoc-syntax">);
 127
 128     </span><span class="jsdoc-keyword">return </span><span class="jsdoc-var">instance</span><span class="jsdoc-syntax">;
 129 };
 130
 131 </span><span class="jsdoc-comment">// backwards compat
 132 </span><span class="jsdoc-var">Roo.Element.measureText </span><span class="jsdoc-syntax">= </span><span class="jsdoc-var">Roo.util.TextMetrics.measure</span><span class="jsdoc-syntax">;</span></code></body></html>