A-EVO-Lab Screenshot & Accessibility Tree Analysis
Reading the Accessibility Tree
The a11y_tree is your primary guide for finding interactive elements:
[role=window] "Document - LibreOffice Calc"
[role=menubar]
[role=menuitem] "File"
[role=menuitem] "Edit"
[role=toolbar]
[role=button] "Save" (x=120, y=45)
[role=table] "Sheet"
[role=cell] "A1" (x=80, y=200)
Coordinate mapping
- a11y_tree provides (x, y) center coordinates for each element
- Use these for pyautogui.click(x, y)
- If coordinates seem wrong, the element may be scrolled off-screen
Element roles cheat sheet
button: clickable action (Save, OK, Cancel)menuitem: menu entry (click to open submenu or execute)textbox/text: editable text field (click then type)combobox: dropdown (click to open, then select)checkbox: toggle (click to check/uncheck)cell: spreadsheet cell (click to select, then type)tab: tab selector (click to switch)dialog: modal window (must handle before other actions)
When a11y_tree is insufficient
- Some custom widgets don't expose a11y info — use screenshot + coordinates
- For canvas-based apps (GIMP): rely on menu navigation, not direct canvas clicks
- For web content in Chrome: a11y_tree reflects DOM, usually reliable
Tips
- Always check a11y_tree AFTER an action to verify the state changed
- If an element disappears from a11y_tree, the UI updated (menu closed, dialog dismissed)
- Count elements to verify you're clicking the right one (e.g., 3rd button in toolbar)