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Custom mouse functions¶
Display one 4-D image layer using the add_image API
import numpy as np
from scipy import ndimage as ndi
from skimage import data
from skimage.morphology import binary_dilation, binary_erosion
import napari
np.random.seed(1)
viewer = napari.Viewer()
blobs = data.binary_blobs(length=128, volume_fraction=0.1, n_dim=2)
labeled = ndi.label(blobs)[0]
labels_layer = viewer.add_labels(labeled, name='blob ID')
@viewer.mouse_drag_callbacks.append
def get_event(viewer, event):
print(event)
@viewer.mouse_drag_callbacks.append
def get_ndisplay(viewer, event):
if 'Alt' in event.modifiers:
print('viewer display ', viewer.dims.ndisplay)
@labels_layer.mouse_drag_callbacks.append
def get_connected_component_shape(layer, event):
data_coordinates = layer.world_to_data(event.position)
cords = np.round(data_coordinates).astype(int)
val = layer.get_value(data_coordinates)
if val is None:
return
if val != 0:
data = layer.data
binary = data == val
if 'Shift' in event.modifiers:
binary_new = binary_erosion(binary)
data[binary] = 0
else:
binary_new = binary_dilation(binary)
data[binary_new] = val
size = np.sum(binary_new)
layer.data = data
msg = (
f'clicked at {cords} on blob {val} which is now {size} pixels'
)
else:
msg = f'clicked at {cords} on background which is ignored'
print(msg)
# Handle click or drag events separately
@labels_layer.mouse_drag_callbacks.append
def click_drag(layer, event):
print('mouse down')
dragged = False
yield
# on move
while event.type == 'mouse_move':
print(event.position)
dragged = True
yield
# on release
if dragged:
print('drag end')
else:
print('clicked!')
# Handle click or drag events separately
@labels_layer.mouse_double_click_callbacks.append
def on_second_click_of_double_click(layer, event):
print('Second click of double_click', event.position)
print('note that a click event was also triggered', event.type)
if __name__ == '__main__':
napari.run()