358638 - Download manager resizes entries on the fly, making selection of entry items unreliable

Status: RESOLVED WORKSFORME

(Toolkit :: Downloads API, defect)

Description

[Ron Mabbitt]

User-Agent:       Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.8.1) Gecko/20061010 Firefox/2.0
Build Identifier: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.8.1) Gecko/20061010 Firefox/2.0

Currently downloading entries are 'double-height' in order to accommodate the progress bar.  When the downloading completes, the bar disappears, and the entry collapses to 'normal-height'.  However, all other items below this entry suddenly 'scroll up' one entry's worth as a result.

This means any attempt to select the 'Remove' button on a lower entry may suddenly find itself selecting the 'Remove' button on the next entry instead, if an entry above suddenly completes during the button selection.

Basically, users are expected to select entries in a table that spontaneously moves, which violates all UI guidelines I know of.

Reproducible: Always

Steps to Reproduce:
1. Download several entries successfully
2. Download a new entry, and then scroll down to a previous entry offscreen from the downloading entry
3. If you attempt to hit the 'Remove' button on this entry during a short window just before to shortly after the currently downloading entry completes, you will find yourself hitting the next entry's delete button.  

Actual Results:  
You end up deleting the entry just below the entry you desired. Note that this can even happen if you managed to click on the right location just before it moved.

Expected Results:  
You should be able to reliably select and delete the entry you desire, and particularly not delete unselected entries.

So long as the entries in the Downloads Manager resize upon completion, you will have spontaneous scrolling of the entries, resulting in this problem.  There needs to be a way to prevent resizing, either by incorporating the scrollbar into the 'normal' size, or perhaps as an option to force all entries to the larger 'double-size'.

Comment 1

[Mike Beltzner [:beltzner, not reading bugmail]]

This is pretty edge to block on, in my opinion. Also, we're looking at some redesign work for the download manager (cc'ing dmose for that reason) so we'll definitely take it into account.

Comment 2

[Shawn Wilsher :sdwilsh]

WORKSFORME on trunk builds