plug-In JavaScript: 100 power Solutions in Java

Creation EAN / UCC - 13 in Java plug-In JavaScript: 100 power Solutions

function HideToggle(id, CB) { if (id instanceof Array) { for (var j = 0 ; j < idlength ; ++j) HideToggle(id[j], CB) return } if (S(id)display != 'none') Hide(id, CB) else Show(id, CB) }

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rom this point on, the plug-ins really start to get interesting as most of the core functions have now been covered Using the tools already outlined, the plug-ins in this chapter enable you to slide objects around the screen, deflate, and inflate objects over time, and zoom objects in a variety of ways With all of this, you can create some very impressive effects with only a few lines of code

43 Slide()

This plug-in allows you to slide an object from one place to another over time, making it useful for sliding elements in on demand, hiding and revealing objects, or creating animation effects Figure 6-1 shows an image in the process of sliding from the bottom left to the top right of the browser

This plug-in moves an object from one location to another over a period of time It supports single objects only (not arrays) because if there were more than one object, only the topmost one would be seen Therefore, you can pass only an object or an object ID to this plug-in It requires the following arguments:

Either an object or an object ID it cannot be an array of objects The top left corner of the initial position for id The top left corner of the final position for id

interruptible If true (or 1), this plug-in can be interrupted by a new call on the same object; if false (or 0), the call is uninterruptible

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stepx stepy count len1 len2 SL_Flag SL_Int SL_IID INTERVAL Distance() DoSlide() GoTo() setInterval() clearInterval() Local variable containing the amount by which to move horizontally in each step Local variable containing the amount by which to move vertically in each step Local variable to count the steps Local variable containing the start to end distance Local variable containing the new start to end distance after an animation is interrupted and given now coordinates New property assigned to id: true when a slide is in progress, otherwise false or unset New property assigned to id: true if the previous call to this plugin set the slide to uninterruptible New property assigned to id with which the repeating interrupts can be stopped Global variable with the value 30 Subfunction to calculate the distance between two locations Subfunction to perform the sliding animation Plug-in to move an object to a new location Function to set another function to be called repeatedly Function to stop the interrupts created by setInterval()

The first section of code tests for the existence of the SL_Flag property of id If it has a value of true (or 1) then a slide on id is already in progress This is the statement used:

if (O(id)SL_Flag)

Next, the property of id, SL_Int is tested If it is false then the previous call to Slide() for this id set this variable to indicate that the function could not be interrupted, so the function returns Otherwise, interrupting the plug-in is allowed, so the current slide is stopped by calling clearInterval(), passing it the SL_IID property of id, as returned by SetInterval() The code to do this is as follows:

if (!O(id)FL_Int) return else clearInterval(O(id)SL_IID)

Next, because the plug-in has been interrupted, it s necessary to allow the interrupting slide to commence from wherever the previous one was halted What s more, because the coordinates of the halted object will not be the start coordinates passed to the interrupting