Decouple Hatch Color and Edge Color Matplotlib

hatch_color.py

import matplotlib.pyplot as plt
import matplotlib.patches as mpatches

def hatch_bar(ax, x, y, hatch='///', hatch_color='blue',
              edge_color='black', lw=1.5, **kwargs):

    bars = ax.bar(
        x, y,
        facecolor='white',
        edgecolor=hatch_color,
        hatch=hatch,
        linewidth=0,
        **kwargs
    )

    for bar in bars:
        ax.add_patch(
            mpatches.Rectangle(
                (bar.get_x(), bar.get_y()),
                bar.get_width(),
                bar.get_height(),
                fill=False,
                edgecolor=edge_color,
                linewidth=lw
            )
        )

    return bars


def hatch_legend(label, hatch='///', hatch_color='blue'):
    return mpatches.Patch(
        facecolor='white',
        edgecolor=hatch_color,
        hatch=hatch,
        label=label
    )
  
 

x = [1, 2, 3]
y = [3, 5, 2]

ax = plt.gca()

bars = ax.bar(
    x, y,
    facecolor='white',
    edgecolor='blue',   # <-- hatch color
    hatch='///',
    linewidth=0         # hide default border
)

# Add a separate border layer (black outline)
for bar in bars:
    ax.add_patch(
        mpatches.Rectangle(
            (bar.get_x(), bar.get_y()),
            bar.get_width(),
            bar.get_height(),
            fill=False,
            edgecolor='black',
            linewidth=1.5
        )
    )

# --- Legend that matches hatch layer exactly ---
legend_patch = mpatches.Patch(
    facecolor='white',
    edgecolor='blue',   # hatch color
    hatch='///',
    label='My Data'
)

ax.legend(handles=[legend_patch])

plt.show()