 
            | Working with PrizmDoc > Developer Guide > Customizing the Viewing Client > Customization Examples > Creating a Custom Mouse Tool | 
A custom mouse tool can be used in the Viewing Client, first by defining the tool and then by updating the UI to have a button for the tool.
It doesn’t matter where in code the tool is defined as long as it is defined before the tool is selected:
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| // Create the new mouse tool. var myTool = PCCViewer.MouseTools.createMouseTool( "PinkLine", PCCViewer.MouseTool.Type.LineAnnotation); // Configure the tool to draw a pink (#FF69B4) line that is 10 pixel thick myTool.getTemplateMark() .setColor("#FF69B4") .setThickness(10); | |
This modification will take place in the viewerTemplate.html file. The button can be added to several places in the UI, but a common place to add the button is in the annotate tab pane. Content of the annotate tab is defined in the element with attribute data-pcc-nav-tab="annotate":
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<!-- The following markup will create a button that enables use
     of the mouse tool named "PinkLine".
     The custom attributes that are used:
      * data-pcc-mouse-tool="PinkLine" - specifies that the button selects the mouse tool named "MyLineTool"
      * data-pcc-context-menu="false" - specifies that a context menu is not shown for this mouse tool
     -->
<button
    data-pcc-mouse-tool="PinkLine"
    data-pcc-context-menu="false"
    class="pcc-icon pcc-icon-annotate-line"
    title="Pink Line Tool"></button>
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