Are icons and other clickable objects easily recognised in programming terms as being

[stevenhales]

Are icons and other clickable objects easily recognised in programming terms as being clickable?

For instance when you use Internet explorer, firefox, etc.. etc.. and then press the TAB button on your keyboard, the buttons/fields on the webpage are highlighted or selected. This therefore makes me think that everything clickable or selectable is given a unique tag with which to find easily. Where does your TAB button get this information from - so to speak???

On a seperate topic, does anyone know how you could compare the position of a mouse pointer with that of clickable objects on the screen? I imagine that the pointing software creates a grid behind the scenes and the mouse pointer has certain co-ordinates on that grid. And I guess the HTML of a webpage could be interogated for the position of certain objects. Any thoughts as to how these could be compared?

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Ste

 

[Iron_Cross]

With JavaScript you can mess with mouse coordinates. The top left corner of your screen is Y=0 X=0 as you move further to the right X increases as you move further down the page Y increases.

As for the TAB thing...It's determined by the tabindex attribute I believe if you put a -1 as the argument it means the tab will not stop on that object. It starts at 0 and continues all the way for as long as you have numbers.

[img]/someImage.jpg[/img]

 

[stevenhales]

I see, and is the tab index compulsary in HTML? Because if this was used as an index, every single object would need to be included that appears on the screen.

 

[Iron_Cross]

edit

 

[jinexile]

No the tab index is not compulsory, but if you do not define it you are leaving the webbrowser to assume what it is and not every browser will guess the same.