<!--Copyright (C) 1988-2005 by the Institute of Global Environment and Society (IGES). See file COPYRIGHT for more information.--> <html> <head> <title>GrADS Command: q pos</title> </head> <body bgcolor="e0f0ff" text="#000000"> <h2><b>q pos</b></h2> <p> After this command is issued, GrADS waits for user's mouse click, then returns the coordinates of the mouse click plus additional information. It is the returned information that makes '<code>q pos</code>' such a powerful command especialy when used in conjunction with the different 'classes' of widgets: buttons, rubber bands, and dropmenus. Here is a template of the information that '<code>q pos</code>' returns after a mouse click (note the difference in output between the different widget classes): <p> <code>Position = <i>xpos ypos mbtn class </i>                                  </code> (somewhere in the graphics window) <br> <code>Position = <i>xpos ypos mbtn class widget# btnstate</i>                  </code> (for buttons) <br> <code>Position = <i>xpos ypos mbtn class widget# xpos2 ypos2</i>               </code> (for rbands) <br> <code>Position = <i>xpos ypos mbtn class widget# menuitem <casc# cascitem></i> </code> (for dropmenus) <br> <p> where: <ul> <code><i>xpos, ypos</i>    </code> - coordinates of the mouse click in virtual page units <br> <code><i>mbtn</i>          </code> - either 1, 2, or 3 for the left, center, or right mouse button <br> <code><i>class</i>         </code> - either 1, 2, 3, or 0 for button, rband, dropmenu, or 'not a widget' <br> <code><i>widget#</i>       </code> - the number assigned to the widget when it was originally set up <br> <code><i>btnstate</i>      </code> - either 0 (meaning "off") or 1 (meaning "on") <br> <code><i>xpos2, ypos2</i>  </code> - coordinates of the mouse release point in virtual page units <br> <code><i>menuitem</i>      </code> - the item number selected from the menu list <br> <code><i>casc#</i>         </code> - the cascade menu number selected from the dropmenu list <br> <code><i>cascitem</i>      </code> - the item number selected from the cascade menu <br> </ul> <p> <h3>Usage Notes</h3> <ol> <li>If the user did not click on a widget, then <code><i>class</i></code> will be 0 and there will be no further output. <p> <li>If the user clicks on a dropmenu but no menu item is selected, then <code><i>widget#</i></code> and <code><i>menuitem</i></code> will both be -1. <p> <li>There can be up to three levels of nested cascading dropmenus launched from the main dropmenu. In other words, <code><i>casc#</i></code> and <code><i>cascitem</i></code> will repeat up to three times in the output from '<code>q pos</code>'. <p> <li> The following reference pages contain information on configuring and drawing the widgets:<br> <a href="gradcomdsetbutton.html"><code>set button</code></a> <br> <a href="gradcomddrawbutton.html"><code>draw button</code></a> <br> <a href="gradcomdredrawbutton.html"><code>redraw button</code></a> <br> <a href="gradcomdsetrband.html"><code>set rband</code></a> <br> <a href="gradcomdsetdropmenu.html"><code>set dropmenu</code></a> <br> <a href="gradcomddrawdropmenu.html"><code>draw dropmenu</code></a> </ol> <p> <h3>Examples </h3> <p> See the section of the User's Guide on <a href="script.html#widgets">widgets</a> for plenty of script examples showing how to use 'q pos'. </body> </html>
