Drag and drop support in main_window

prasopes/__main__.py

@@ -20,12 +20,14 @@ import os.path
 matplotlib.use("Qt5Agg")
 
 
-def load_file(chrom_plot, spc, d_set, ms_s, fn, chrom_s, settings):
+def load_file(chrom_plot, spc, d_set, ms_s, fn, chrom_s, settings,
+              filename=None):
     """populates dataset and plots it"""
     directory=settings.value("open_folder")
     if fn[0] is not None:
         directory=fn[0]
-    filename = QtWidgets.QFileDialog.getOpenFileName(
+    if filename == None:
+        filename = QtWidgets.QFileDialog.getOpenFileName(
             caption="Open spectrum",
             directory=directory,
             filter="Finnigan RAW files (*.raw, *.RAW)")[0]
@@ -48,6 +50,19 @@ def update_spectrum(event, chromatogram, spect, ds,
         spect.get_figure().canvas.draw()
 
 
+def dropped(event, chromatogram, spectrum, ds, ms, filename, chrom,
+            config):
+    dropurl = event.mimeData().urls()[0].path()
+    load_file(chromatogram, spectrum, ds, ms, filename, chrom,
+                  config, filename=dropurl)
+
+
+def drag_entered(event):
+    if event.mimeData().hasUrls() and event.mimeData().urls()[0]\
+        .path().lower().endswith('.raw'):
+        event.accept()
+
+
 def main():
     # ds for data_set, ms for mass_spec_dataset, chrom for chrom_dataset
     ds = dict(chrom_dat=None, masses=None, matrix=None)
@@ -133,8 +148,6 @@ def main():
     autozoomy.triggered.connect(lambda: gt.autozoomy(
         autozoomy.isChecked(), spectrum, ms))
 
-
-
     file_menu = QtWidgets.QMenu('&File', main_window)
     main_window.menuBar().addMenu(file_menu)
     file_menu.addAction(openact)
@@ -173,14 +186,15 @@ def main():
     mpl_canvas.mpl_connect('key_press_event', lambda event:
         update_spectrum(event, chromatogram, spectrum, ds, ms,
                         filename, chrom, config))
-
+    main_window.dragEnterEvent = lambda event: drag_entered(event)
+    main_window.dropEvent = lambda event: dropped(
+        event, chromatogram, spectrum, ds, ms, filename, chrom,
+        config)
+    main_window.setAcceptDrops(True)
 
     if len(sys.argv) == 2:
-        raw_file = sys.argv[1]
-        filename[0] = raw_file
-        ds['chrom_dat'], ds['masses'], ds['matrix'] = load_raw(
-                raw_file, config.value("tmp_location"))
-        gt.populate(chromatogram, spectrum, ds, ms, chrom)
+        load_file(chromatogram, spectrum, ds, ms, filename, chrom,
+                  config, filename=sys.argv[1])
     else:
         gt.pop_plot(spectrum, ms)
         gt.pop_plot(chromatogram, chrom)