Cannot get keymap for IMAGE_EDITOR to work

Question

I am trying to create a keymap to scale the selected verts in the UV Editor to zero in the X direction. The code below works correctly in the UV Editor with F3 and find operator "Scale UV selected verts to X=0"

So that's all good.

When I bind a keymap to the space_type 'IMAGE_EDITOR', it shows up as registered in PREFS, but does not execute when I press Shift+Ctrl+X. What am I doing wrong? FWIW, I've tried numerous different key combinations with no success. Thanks for any help.

import bpy

# SCALE X IN UV EDITOR
class OBJECT_OT_scale_xuv(bpy.types.Operator):
    """scales VERTS to x=0"""
    bl_idname = "object.vertscale_xuv"
    bl_label = "Scale UV selected verts to X=0"

    def execute(self, context):
        
        bpy.ops.transform.resize(value=(0, 1, 1), orient_type='VIEW', orient_matrix=((1, 0, 0), (0, 1, 0), (0, 0, 1)), 
            orient_matrix_type='VIEW', constraint_axis=(True, False, False), 
            mirror=True, use_proportional_edit=False, proportional_edit_falloff='SMOOTH', 
            proportional_size=1, use_proportional_connected=False, use_proportional_projected=False)
        
        return {'FINISHED'}


addon_keymaps = []

def registerKeymaps():
    wm = bpy.context.window_manager
    if wm.keyconfigs.addon:
       
        # KEY SHORTCUTS FOR SPACE TYPE IMAGE_EDITOR
        km_uv = wm.keyconfigs.addon.keymaps.new(name='Image Editor Tool: Uv, Scale', space_type='IMAGE_EDITOR')
        
        ## SCALE UV VERTS X
        km_uv_i = km_uv.keymap_items.new('object.vertscale_xuv', 'X', 'PRESS', shift=True, ctrl=True)
        addon_keymaps.append((km_uv, km_uv_i))



def unregisterKeymaps():
    for km, kmi in addon_keymaps:
        km.keymap_items.remove(kmi)
    addon_keymaps.clear()


def register():
    bpy.utils.register_class(OBJECT_OT_scale_xuv)
    registerKeymaps()

def unregister():
    unregisterKeymaps()
    bpy.utils.unregister_class(OBJECT_OT_scale_xuv)

if __name__ == "__main__":
    register()

Answer 1

Pass 'Image' as the name and 'IMAGE_EDITOR' as space_type to keymaps.new(), and the registration works as expected. CtrlY demo based on the Operator Simple template:

import bpy

class SimpleOperator(bpy.types.Operator):
    """Tooltip"""
    bl_idname = "image.simple_operator"
    bl_label = "Simple Image Operator"

    def execute(self, context):
        print(SimpleOperator.bl_idname, "called")
        return {'FINISHED'}

addon_keymaps = []
def register():
    bpy.utils.register_class(SimpleOperator)
    addon_keymaps.clear()

    wm = bpy.context.window_manager # handle the keymap
    kc = wm.keyconfigs.addon
    if kc:
        km = wm.keyconfigs.addon.keymaps.new(name='Image', space_type='IMAGE_EDITOR')
        kmi = km.keymap_items.new(
            SimpleOperator.bl_idname, type='Y', value='PRESS', ctrl=True)
        addon_keymaps.append((km, kmi))

def unregister():
    bpy.utils.unregister_class(SimpleOperator)

    for km, kmi in addon_keymaps:
        km.keymap_items.remove(kmi)
    addon_keymaps.clear()

if __name__ == "__main__":
    register()

If you would like to limit the hotkey to only work when editing UV's, just add a poll method to your operator asking for an active UV map or whether there is an image loaded at all:

    @classmethod
    def poll(cls, context):
        sima = context.space_data
        return sima.show_uvedit and sima.image is None

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