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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: fig.savefig throws error after radiobutton axes is removed","articleBody":"### Bug summary\n\nIf I create a figure with a radiobutton widget and then remove the radio widget axes in order to save the figure without the radiobutton  box shown it throws an error in fig.savefig\n\n### Code for reproduction\n\n```Python\nimport numpy as np\nimport matplotlib.pyplot as plt\nfrom matplotlib.widgets import RadioButtons\n\n# data creation\nx = np.arange(0.0, 3.0, 0.01)\ny = np.sin(2*np.pi*x)\n\n# plotting data\nfig, ax = plt.subplots()\nl, = ax.plot(x, y)\nplt.subplots_adjust(left = 0.3)\n\n# creating radio buttons\nrax = plt.axes([0.05, 0.5, 0.15, 0.30])\nradio = RadioButtons(\n    rax, labels = ['red', 'blue', 'green'], active=2, activecolor='black')\nl.set_color(radio.value_selected)\n\ndef color(label):\n    l.set_color(label)\n    fig.canvas.draw()\n\nradio.on_clicked(color)\n\nplt.show()\n\n# remove radio buttons axes\nradio.ax.remove()\n\nfig.tight_layout()\nfig.savefig('figure.png')\n```\n\n### Actual outcome\n\nTraceback (most recent call last):\n  File \"/nfs/chess/user/rv43/miniforge3/envs/CHAP_tomo/lib/python3.10/site-packages/matplotlib/cbook.py\", line 298, in process\n    func(*args, **kwargs)\n  File \"/nfs/chess/user/rv43/miniforge3/envs/CHAP_tomo/lib/python3.10/site-packages/matplotlib/widgets.py\", line 1665, in _clear\n    if self.ignore(event) or self.canvas.is_saving():\n  File \"/nfs/chess/user/rv43/miniforge3/envs/CHAP_tomo/lib/python3.10/site-packages/matplotlib/widgets.py\", line 120, in \u003clambda\u003e\n    canvas = property(lambda self: self.ax.figure.canvas)\nAttributeError: 'NoneType' object has no attribute 'canvas'\nTraceback (most recent call last):\n  File \"/nfs/chess/user/rv43/miniforge3/envs/CHAP_tomo/lib/python3.10/site-packages/matplotlib/cbook.py\", line 298, in process\n    func(*args, **kwargs)\n  File \"/nfs/chess/user/rv43/miniforge3/envs/CHAP_tomo/lib/python3.10/site-packages/matplotlib/widgets.py\", line 1665, in _clear\n    if self.ignore(event) or self.canvas.is_saving():\n  File \"/nfs/chess/user/rv43/miniforge3/envs/CHAP_tomo/lib/python3.10/site-packages/matplotlib/widgets.py\", line 120, in \u003clambda\u003e\n    canvas = property(lambda self: self.ax.figure.canvas)\nAttributeError: 'NoneType' object has no attribute 'canvas'\n\n\n### Expected outcome\n\nThis example does produce the correct figure (one with a tight layout and no radiobuttons box), since the error that is thrown is caught by matplotlib and only printed as a warning.\n\n### Additional information\n\nIn matplotlib/widgets.py:\nReplacing:\n    def _clear(self, event):\n        \"\"\"Internal event handler to clear the buttons.\"\"\"\n        if self.ignore(event) or self.canvas.is_saving():\n            return\n        self._background = self.canvas.copy_from_bbox(self.ax.bbox)\n        self.ax.draw_artist(self._buttons)\nWith:\n    def _clear(self, event):\n        \"\"\"Internal event handler to clear the buttons.\"\"\"\n        if self.ax._stale or self.ignore(event) or self.canvas.is_saving():\n            return\n        self._background = self.canvas.copy_from_bbox(self.ax.bbox)\n        self.ax.draw_artist(self._buttons)\nSuppresses the issue, but I'm not sure if that is the desired fix or if self.ax._stale has another purpose. I have not tested CheckButtons widgets, but I'm wondering if the same happens there.\n\nIt may be wrapped up in self.ignore(event) by setting self.active = False when the radiobuttons get removed, but I don't know if that has other side effects.\n\n### Operating system\n\nScientific Linux 7, AlmaLinux-9\n\n### Matplotlib Version\n\n3.9.2, 3.10.3\n\n### Matplotlib Backend\n\nqtagg\n\n### Python version\n\n3.10.18\n\n### Jupyter version\n\nN/A\n\n### Installation\n\nconda","author":{"url":"https://github.com/rolfverberg","@type":"Person","name":"rolfverberg"},"datePublished":"2025-07-17T16:23:47.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":7},"url":"https://github.com/30325/matplotlib/issues/30325"}