Gets the first image.
<p>
The image in column 0 is reserved for the [+] and [-]
images of the tree, therefore getImage(0) will return null.
@return the image at index 0
@exception SWTException <ul>
<li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
<li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
</ul>
Gets the first image. <p> The image in column 0 is reserved for the [+] and [-] images of the tree, therefore getImage(0) will return null.
@return the image at index 0
@exception SWTException <ul> <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> </ul>