I wanted to talk today about the interaction between Web Viewers and other objects within the same visible space. Most importantly, I wanted to discuss the functionality of how a Web Viewer draws on the screen. As documented by FileMaker, a Web Viewer will be drawn over all other objects, excluding tab controls and slide controls, and portals (Web Viewers cannot be placed in a portal). What this means is that any object placed within the rectangle space of the Web Viewer will be drawn over and will not be visible.
For a visible representation, please see the following image:
The image above, besides the lovely Google animation, shows a Web Viewer covering part of a button with the label My Button and a blue background. The button actually extends into the space of the Web Viewer. However, due to a Web Viewer being drawn over all other objects, the bottom half of the button is not visible. This can lead to some unusual behavior.
Before describing this behavior, let’s take a look at the following image:
This is a very simple layout that consists of a single Web Viewer, a button that controls the visibility of the Web Viewer, and a single popover button. The popover button is within the rectangle space of the Web Viewer and therefore hidden from our view.
It can be seen in this image when the Web Viewer is hidden:
Now, the bizarre behavior that occurs is when we have a situation in our second screenshot; where the Web Viewer is visible and drawn over our popover button. If a user were to click the exact location of the popover button, they would be able to activate it, despite that it cannot be seen. This can be seen in the following image:
What this means is that FileMaker may draw Web Viewers over all other objects, but it does not alter the Object Layer Hierarchy. Explaining further, objects on top of a Web Viewer will still function as if they are the front objects, despite being drawn over by the Web Viewer. Keep this in mind when designing layouts with Web Viewers and other objects.