Explorer widget

napari_explorer.py

from __future__ import annotations
from qtpy.QtWidgets import QWidget, QFileSystemModel, QTreeView, QGridLayout, QPushButton, QFileDialog
from qtpy.QtCore import Qt, QModelIndex
import os
from skimage import io
import napari


class Explorer(QWidget):
    def __init__(self, viewer:"napari.Viewer", path:str=""):
        super().__init__(viewer.window._qt_window)
        self.viewer = viewer
        self.setLayout(QGridLayout())
        
        self._add_change_root_button()
        self._add_filetree(path)
    
    def _add_change_root_button(self):
        self.root_button = QPushButton(self)
        self.root_button.setText("Change root directory")
        @self.root_button.clicked.connect
        def _():
            dlg = QFileDialog()
            dlg.setFileMode(QFileDialog.DirectoryOnly)
            dlg.setHistory([self.tree.rootpath])
            dirname = dlg.getExistingDirectory(self, caption="Select root ...", directory=self.tree.rootpath)
            if dirname:
                self.tree.rootpath = dirname
                self.tree._set_file_model(dirname)
                napari.utils.history.update_open_history(dirname)
            return None
        
        self.layout().addWidget(self.root_button)
        return None
    
    def _add_filetree(self, path:str=""):
        """
        Add tree view of files with root directory set to ``path``.

        Parameters
        ----------
        path : str, default is ""
            Path of the root directory. If not found, current directory will be used.
        """        
        path = os.getcwd() if not os.path.exists(path) else path
        self.tree = FileTree(self, path)
        self.layout().addWidget(self.tree)
        return None
    
class FileTree(QTreeView):
    def __init__(self, parent, path:str):
        super().__init__(parent=parent)
        
        self.viewer = parent.viewer
        self.rootpath = path
        self.setContextMenuPolicy(Qt.CustomContextMenu)
        self.setUniformRowHeights(True)
        self.header().hide()

        # Set QFileSystemModel
        self.file_system = QFileSystemModel(self)
        self.file_system.setReadOnly(True)
        self.file_system.setNameFilterDisables(False)
        self._set_file_model(path)
        
        # hide columns except for name
        for i in range(1, self.file_system.columnCount()):
            self.hideColumn(i)
            
        self.doubleClicked.connect(self.onDoubleClicked)
        
        self.show()
    
    def _set_file_model(self, path:str):
        self.file_system.setRootPath(path)
        self.setModel(self.file_system)
        self.setRootIndex(self.file_system.index(path))
        return None
    
    
    def open_path_at(self, index:QModelIndex):
        path = self.file_system.filePath(index)
        self.viewer.add_image(io.imread(path))
        return None
        
        
    def onDoubleClicked(self, index:QModelIndex):
        path = self.file_system.filePath(index)
        if os.path.isfile(path):
            self.open_path_at(index)
        else:
            return None
        
    def keyPressEvent(self, event):
        if event.key() == Qt.Key_Return:
            index = self.selected
            index is None or self.onDoubleClicked(index)
        else:
            return super().keyPressEvent(event)
    
    @property
    def selected(self) -> QModelIndex:
        inds = self.selectionModel().selectedIndexes()
        if len(inds) > 0:
            index = inds[0]
        else:
            index = None
        return index

if __name__ == "__main__":
    viewer = napari.Viewer()
    ex = Explorer(viewer) 
    viewer.window.add_dock_widget(ex)
    napari.run()