Hiding part of gridline labels

[paalge]

Description

I am running the latest master branch 0e5eef8 as I want to add labels for a proj4 grid.
This is working very well, thank you for the work you've put in.

When I want to remove some of the labels, following the example in https://scitools.org.uk/cartopy/docs/v0.17/matplotlib/gridliner.html none of the labels are removed.

Code to reproduce

From the example running on python 3.6.8

import matplotlib.pyplot as plt
import matplotlib.ticker as mticker
import cartopy.crs as ccrs

from cartopy.mpl.gridliner import LONGITUDE_FORMATTER, LATITUDE_FORMATTER


ax = plt.axes(projection=ccrs.Mercator())
ax.coastlines()

gl = ax.gridlines(crs=ccrs.PlateCarree(), draw_labels=True,
                  linewidth=2, color='gray', alpha=0.5, linestyle='--')
gl.xlabels_top = False
gl.ylabels_left = False
gl.xlines = False
gl.xlocator = mticker.FixedLocator([-180, -45, 0, 45, 180])
gl.xformatter = LONGITUDE_FORMATTER
gl.yformatter = LATITUDE_FORMATTER
gl.xlabel_style = {'size': 15, 'color': 'gray'}
gl.xlabel_style = {'color': 'red', 'weight': 'bold'}

plt.show()

Full environment definition

Operating system

Linux Mint 19.2

Cartopy version

0e5eef8

pip3 list

aggdraw (1.3.11)
apt-clone (0.2.1)
apturl (0.5.2)
arrow (0.15.2)
asciitree (0.3.3)
attrs (19.1.0)
autopep8 (1.4.4)
backcall (0.1.0)
beautifulsoup4 (4.6.0)
bleach (3.1.0)
blessings (1.6)
bpython (0.17.1)
Brlapi (0.6.6)
Cartopy (0.17.1.dev174-)
catfish (1.4.4)
certifi (2019.6.16)
cftime (1.0.3.4)
chardet (3.0.4)
Click (7.0)
cloudpickle (1.2.2)
command-not-found (0.3)
configobj (5.0.6)
cupshelpers (1.0)
curtsies (0.2.12)
cycler (0.10.0)
Cython (0.29.13)
dask (2.5.2)
decorator (4.4.0)
defer (1.0.6)
defusedxml (0.6.0)
dokuwikixmlrpc (2010-07-19)
entrypoints (0.3)
fasteners (0.15)
fsspec (0.5.2)
GDAL (2.2.2)
geojson (2.5.0)
geomet (0.2.1)
greenlet (0.4.12)
h5netcdf (0.7.4)
h5py (2.10.0)
hdf5storage (0.1.14)
html2text (2019.8.11)
html5lib (0.999999999)
httplib2 (0.9.2)
idna (2.8)
imageio (2.5.0)
ipykernel (5.1.2)
ipympl (0.3.3)
ipython (7.7.0)
ipython-genutils (0.2.0)
ipywidgets (7.5.1)
jedi (0.15.1)
Jinja2 (2.10.1)
json5 (0.8.5)
jsonschema (3.0.2)
jupyter-client (5.3.1)
jupyter-core (4.5.0)
jupyterlab (1.0.4)
jupyterlab-server (1.0.0)
kiwisolver (1.1.0)
locket (0.2.0)
louis (3.5.0)
Mako (1.0.7)
MarkupSafe (1.1.1)
matplotlib (3.1.1)
menulibre (2.2.0)
mistune (0.8.4)
monotonic (1.5)
mugshot (0.4.0)
nbconvert (5.6.0)
nbformat (4.4.0)
netCDF4 (1.5.2)
netifaces (0.10.4)
networkx (2.3)
notebook (6.0.0)
notedown (1.5.1)
numcodecs (0.6.3)
numpy (1.17.2)
onboard (1.4.1)
pandas (0.25.1)
pandoc-attributes (0.1.7)
pandocfilters (1.4.2)
parso (0.5.1)
partd (1.0.0)
pexpect (4.7.0)
pickleshare (0.7.5)
Pillow (6.2.0)
pip (9.0.1)
primefac (1.1)
proj (0.1.0)
prometheus-client (0.7.1)
prompt-toolkit (2.0.9)
psutil (5.4.2)
ptyprocess (0.6.0)
pycairo (1.16.2)
pycoast (1.2.3)
pycodestyle (2.5.0)
pycrypto (2.6.1)
pycups (1.9.73)
pycurl (7.43.0.1)
Pygments (2.4.2)
pygobject (3.26.1)
PyICU (1.9.8)
pykdtree (1.3.1)
pyorbital (1.5.0)
pyparsing (2.4.2)
pyproj (2.4.0)
pyresample (1.13.1)
pyrsistent (0.15.4)
pyshp (2.1.0)
pysmbc (1.0.15.6)
python-apt (1.6.4)
python-dateutil (2.8.0)
python-debian (0.1.32)
python-geotiepoints (1.1.8)
python-xapp (1.6.0)
python-xlib (0.20)
pytz (2019.3)
PyWavelets (1.0.3)
pyxdg (0.25)
PyYAML (3.12)
pyzmq (18.1.0)
reportlab (3.4.0)
requests (2.22.0)
requests-unixsocket (0.1.5)
satpy (0.17.0, /home/pal/gitRepo/satpy)
scikit-image (0.15.0)
scipy (1.3.1)
screen-resolution-extra (0.0.0)
Send2Trash (1.5.0)
sentinelsat (0.13)
sessioninstaller (0.0.0)
setproctitle (1.1.10)
setuptools (41.0.1)
Shapely (1.6.4.post2)
simplegeneric (0.8.1)
six (1.12.0)
system-service (0.3)
systemd-python (234)
terminado (0.8.2)
testpath (0.4.2)
toolz (0.10.0)
tornado (6.0.3)
tqdm (4.35.0)
traitlets (4.3.2)
trollimage (1.10.1)
trollsift (0.3.2)
ubuntu-drivers-common (0.0.0)
ufw (0.36)
urllib3 (1.25.3)
wcwidth (0.1.7)
webencodings (0.5.1)
wheel (0.33.6)
widgetsnbextension (3.5.1)
xarray (0.12.3)
xkit (0.0.0)
zarr (2.3.2)

[dopplershift]

I can reproduce this locally on current master. It worked fine for me on 0.17.0, so definitely a regression.

[greglucas]

Just looked into this. This is because the label attributes were apparently changed. They are now bottom_labels, etc... instead of with the x/y qualifiers. I just made a PR to hopefully allow some deprecation with this as I didn't see any documentation for this change.