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Adding the Drag-Scrollbar and Necessary Trigger (cont.)Step 2 (cont.): Starting at frame 1, going to frame 2, going to frame 3 and going back to frame 2, it will keep looping between frame 2 and 3. These actions will continuously keep readjusting the scroll positon of the text. However, see the first action (GetProperty ("slider", _y ) / ../:balkheight), it will be based on the Property Y-position of the instance slider (Movie Clip scroll drag mc). Now, next comes the big trick!! Later on, we will add actions to the scroll Up and Down buttons to tell this Movie Clip to temporarily stop at frame 1 (which has no actions) while the scroll Up or scroll Down is pressed, wait till the user lets go the button and restart the loop between frame 2 and frame 3. But before it starts looping again, the Y-position of slider was reset by the extra actionscript (which we'll add in the end) on the scroll Up and Down buttons, so it takes over this change and starts looping again. We need to do it this way since the Action Scripts for the dragable button are executed nonstop (just paused by scroll Up and Down buttons). In theory it is possible to have the Action Scripts for the dragable button only executed when the button is clicked but this way it's a bit easier ;) But wait, what did this script do? First, it sets a variable called scrollvalue which devides the current position of slider by the maximum position of slider (which is used for the drag-defenitions 0,0,0,../balkheight). This will look at the 'percentage' of the drag button's position, relative to the maximum dragable distance. It will result in a value between 0 and 1. After this, the textposition (scrolltext.scroll) will be reset acordingly. This is done by first getting the maximum scrollvalue scrolltext.maxscroll into a variable called max. Then the current scroll value scrolltext.scroll is recalculated. One might think that the easiest way would be: scrollvalue * max. However, the scrolldistance goes from 0 pixels to 200 pixels while the scrollvalue (line numbers) go from 1 to maximum instead of 0 to maximum. By changing max to (max - 1) + 1 we correct the calculation. By the way, the "Int" is to create whole numbers like 1 and 13 and 45 instead of 1,2330 and 13,29003 and 44,99945. Step 3 : Create a new layer in Movie Clip window and name it scroll drag. Create an empty keryframe at frame 4 an place here an instance of scrollbar. Give it the instance name scroll. Click Control - Test Movie to test if the dragable scroll button is working. Notice ... the scroll Up and Down buttons stopped working correctly. Don't worry, we'll fix that next
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