[Sommaire] [Imprimer]

   1  <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
   2  <HTML>
   3  <HEAD>
   4  <META HTTP-EQUIV="Content-Type" CONTENT="text/html; CHARSET=iso-iso-8859-1">
   5  <LINK REL="Start" HREF="index.html">
   6  <LINK REL="Contents" HREF="toc.html">
   7  <LINK REL="Prev" HREF="821Adjustingthewidthofthebars.html">
   8  <LINK REL="Next" HREF="823Addingadropshadowtothebar.html">
   9  <STYLE TYPE="text/css"><!--
  10  BODY { font-family: serif }
  11  H1 { font-family: sans-serif }
  12  H2 { font-family: sans-serif }
  13  H3 { font-family: sans-serif }
  14  H4 { font-family: sans-serif }
  15  H5 { font-family: sans-serif }
  16  H6 { font-family: sans-serif }
  17  SUB { font-size: smaller }
  18  SUP { font-size: smaller }
  19  PRE { font-family: monospace }
  20  A { text-decoration: none }
  21  --></STYLE>
  22  </HEAD>
  23  <BODY>
  24  <A HREF="toc.html">Contents</A>
  25  <A HREF="821Adjustingthewidthofthebars.html">Previous</A>
  26  <A HREF="823Addingadropshadowtothebar.html">Next</A>
  27  <HR NOSHADE>
  28  <H3><A NAME="8_2_2">8.2.2 Displaying the value of each bar</A></H3>
  29  <P> You can easily choose to display the value (and it's format) on top
  30   of each bar by accessing the bar's 'value' property. So for example by
  31   just adding the line<DIV class="phpscript"><CODE><FONT color="#000000">
  32   <FONT color="#0000BB">&nbsp;$barplot</FONT><FONT color="#007700">-&gt;</FONT><FONT
  33  color="#0000BB">value</FONT><FONT color="#007700">-&gt;</FONT><FONT color="#0000BB">
  34  Show</FONT><FONT color="#007700">();</FONT><FONT color="#0000BB"></FONT></FONT>
  35  </CODE></DIV></P>
  36  <P> Will enable the values in it's simplest form and will give the
  37   result<DIV class="example">
  38  <BR> <A href="exframes/frame_example20.1.html" target="blank"><IMG border="0"
  39  HEIGHT="200"  src="img/example20.1.png" WIDTH="300"></A>
  40  <BR><B>Figure 31:</B> Showing the values for each bar <A href="exframes/frame_example20.1.html"
  41  target="blank">[src]</A>&nbsp;
  42  <P></P>
  43  </DIV></P>
  44  <P> You cane see a small nuisance in this graph. The auto scaling
  45   algorithm chooses quite tight limits for the scale so that the bars
  46   just fit. Adding the value on top of the bar makes it collide with the
  47   top of the graph. To remedy this we tell the auto scaling algorithm to
  48   allow for more &quot;grace&quot; space at the top of the scale by using the
  49   method <A href="../ref/LinearScale.html#_LINEARSCALE_SETGRACE">
  50   SetGrace()</A> which is used to tell the scale to add a percentage (of
  51   the total scale span) more space to either one end or both ends of the
  52   scale. In this case we add 20% more space at the top to make more room
  53   for the values with the line<DIV class="phpscript"><CODE><FONT color="#000000">
  54   <FONT color="#0000BB">&nbsp;$graph</FONT><FONT color="#007700">-&gt;</FONT><FONT
  55  color="#0000BB">yaxis</FONT><FONT color="#007700">-&gt;</FONT><FONT color="#0000BB">
  56  scale</FONT><FONT color="#007700">-&gt;</FONT><FONT color="#0000BB">
  57  SetGrace</FONT><FONT color="#007700">(</FONT><FONT color="#0000BB">20</FONT><FONT
  58  color="#007700">);</FONT><FONT color="#0000BB"></FONT></FONT></CODE></DIV>
  59  </P>
  60  <P></P>
  61  <P> This will then give the graph as shown below<DIV class="example">
  62  <BR> <A href="exframes/frame_example20.2.html" target="blank"><IMG border="0"
  63  HEIGHT="200"  src="img/example20.2.png" WIDTH="300"></A>
  64  <BR><B>Figure 32:</B> Adding some grace space to the top of the Y-scale <A
  65  href="exframes/frame_example20.2.html" target="blank">[src]</A>&nbsp;
  66  <P></P>
  67  </DIV></P>
  68  <P></P>
  69  <P> You can also adjust the general position of the value in respect to
  70   the bar by using the <A href="../ref/BarPlot.html#_BARPLOT_SETVALUEPOS">
  71   BarPlot::SetValuePos()</A> method. You can set the position to either
  72   'top' (the default) , 'center' or 'bottom'. The graph below shows the
  73   value being positioned in the center. In this example we have also
  74   adjusted the format to just display the value as an integer without any
  75   decimals.<DIV class="example">
  76  <BR> <A href="exframes/frame_example20.5.html" target="blank"><IMG border="0"
  77  HEIGHT="200"  src="img/example20.5.png" WIDTH="300"></A>
  78  <BR><B>Figure 33:</B> Putting the values in the middle of the bar. <A href="exframes/frame_example20.5.html"
  79  target="blank">[src]</A>&nbsp;
  80  <P></P>
  81  </DIV></P>
  82  <P> It is also possible to specify a more fine grained control on how
  83   you want the values presented. You can for example, rotate them, change
  84   font, change color. It is also possible to adjust the actual value
  85   displayed by either using a printf()-type format string or with the
  86   more advanced technique of a format callback routine.</P>
  87  <P> To show what you can do we just give another example for you to
  88   examine without much further explanations. Just remember that to have
  89   text at an angle other than 0 or 90 degrees we have to use TTF fonts.
  90   Even though we haven't explained the SetFont() method it should be
  91   fairly obvious.<DIV class="example">
  92  <BR> <A href="exframes/frame_example20.3.html" target="blank"><IMG border="0"
  93  HEIGHT="200"  src="img/example20.3.png" WIDTH="300"></A>
  94  <BR><B>Figure 34:</B> Making the displayed values more interesting <A href="exframes/frame_example20.3.html"
  95  target="blank">[src]</A>&nbsp;
  96  <P></P>
  97  </DIV></P>
  98  <P></P>
  99  <HR NOSHADE>
 100  <A HREF="toc.html">Contents</A>
 101  <A HREF="821Adjustingthewidthofthebars.html">Previous</A>
 102  <A HREF="823Addingadropshadowtothebar.html">Next</A>
 103  </BODY>
 104  </HTML>