[new class] add communicator class for app-wide singaling

communicator.py

@@ -0,0 +1,6 @@
+from PyQt5.QtCore import QObject, pyqtSignal
+
+class Communicate(QObject):
+     open_recent = pyqtSignal(str)
+     
+communicator = Communicate()

main_window.py

@@ -1,13 +1,14 @@
 import sys
 import os
 from typing import Hashable
-from PyQt5.QtWidgets import QFileDialog, QFrame, QLabel, QListWidget, QMainWindow, QMenuBar, QStackedLayout, QToolBar, QAction, QStatusBar, QVBoxLayout, QWidget, QGridLayout, QSpacerItem, QSizePolicy
+from PyQt5.QtWidgets import QFileDialog, QFrame, QLabel, QListWidget, QListWidgetItem, QMainWindow, QMenuBar, QStackedLayout, QToolBar, QAction, QStatusBar, QVBoxLayout, QWidget, QGridLayout, QSpacerItem, QSizePolicy
 from PyQt5.QtGui import QIcon, QPixmap, QKeySequence
 from PyQt5.QtCore import Qt, QSize, QSettings
 from numpy import unique
 
 from file_handler import FileHandler
 import constants as cnst
+import communicator as comm
 
 class NixView(QMainWindow):
     
@@ -24,8 +25,13 @@ class NixView(QMainWindow):
         
         self._cw = CentralWidget(self)
         self.setCentralWidget(self._cw)
+        
+        comm.communicator.open_recent.connect(self.on_open_recent)
         self.show()
 
+    def on_open_recent(self, event):
+        self.open_file(event)
+
     def create_actions(self):
         self._file_open_action = QAction(QIcon("./icons/nix_open.png"), "Open", self)
         self._file_open_action.setStatusTip("Open nix file")
@@ -74,20 +80,23 @@ class NixView(QMainWindow):
         new_filenames = list(unique(new_filenames))
         settings.setValue(cnst.settings_recent_files_key, new_filenames)
         del settings
-        
+    
+    def open_file(self, filename):
+        success, msg = self._file_handler.open(filename)
+        self.statusBar().showMessage(msg, 5000)
+        if success:
+            self._file_close_action.setEnabled(success)
+            self._cw.show_file_content()
+            self._update_recent_files(filename)
+
     def on_file_open(self, s):
         dlg = QFileDialog(self, 'Open nix data file', '', "NIX files (*.h5 *.nix)")
         dlg.setFileMode(QFileDialog.ExistingFile)
         filenames = None
         if dlg.exec_():
             filenames = dlg.selectedFiles()
-            success, msg = self._file_handler.open(filenames[0])
+            self.open_file(filenames[0])
-            self.statusBar().showMessage(msg, 5000)
+            
-            if success:
-                self._file_close_action.setEnabled(success)
-                self._cw.show_file_content()
-                self._update_recent_files(filenames[0])
-
     def on_file_close(self, s):
         self._file_handler.close()
         self._cw.reset()
@@ -104,10 +113,10 @@ class CentralWidget(QWidget):
     def __init__(self, parent=None) -> None:
         super().__init__(parent=parent)
         
-        splash = SplashScreen()
+        self._splash = SplashScreen()
         self._file_view = FileView(self)
         self._stack = QStackedLayout(self)
-        self._stack.addWidget(splash)
+        self._stack.addWidget(self._splash)
         self._stack.addWidget(self._file_view)
         self.setLayout(self._stack)
         self.setStyleSheet("background-color: white;")
@@ -117,6 +126,7 @@ class CentralWidget(QWidget):
 
     def reset(self):
         self._file_view.reset()
+        self._splash.reset()
         self._stack.setCurrentIndex(0)
 
 
@@ -158,31 +168,38 @@ class SplashScreen(QWidget):
         
         self._file_list = QListWidget(self)
         self._file_list.itemClicked.connect(self._on_file_clicked)
-        self._file_list.itemDoubleClicked.connect(self._on_file_clicked)
         l.addWidget(self._file_list)
         frame.setLayout(l)
         layout.addWidget(frame, 3, 1)
         self._file_map = {}
         self._read_recent_files()
         
-    def _create_short_filename(original, max_len=40):
+    def _create_short_filename(self, original, index, max_len=40):
         short = original
         parts = original.split(os.sep)
-        print(parts)
+        post = parts[-1]
+        if len(post) > max_len - 4:
+            post = post[:max_len - 4]
+            short = str("%i: " % index) + "... " + post
+        else:
+            short = str("%i: " % index) + " ... ".join([original[:max_len - len(post) - 4], post])
         return short
         
     def _read_recent_files(self):
         settings = QSettings(cnst.organization, cnst.application)
         filenames = settings.value(cnst.settings_recent_files_key, [])
         del settings
-        
+
-        for f in filenames:
+        for i, f in enumerate(filenames):
-            shortname = _create_short_filename(f, max_len=40)
+            shortname = self._create_short_filename(f, i + 1, max_len=38)
-            self._file_map[f] =shortname
+            self._file_map[shortname] = f
-            self._file_list.addItem(self._file_map[f])
+            item = QListWidgetItem(shortname)
-
+            item.setToolTip(f)
-                
+            self._file_list.addItem(item)
-    def _on_file_clicked(self, s):
+
-        print(s)
+    def reset(self):
-    
+        self._file_list.clear()
-    
+        self._read_recent_files() 
+
+    def _on_file_clicked(self, item):
+        comm.communicator.open_recent.emit(self._file_map[item.text()])