Add delete button for layers

gui/elements/_layer_list.py

@@ -4,7 +4,7 @@
 from vispy.util.event import EmitterGroup, Event
 from ..layers._base_layer import Layer
 
-from .qt import QtLayerList
+from .qt import QtLayerPanel
 
 
 class ItemEvent(Event):
@@ -47,7 +47,7 @@ class LayerList:
 
     def __init__(self, viewer=None):
         self._list = []
-        self._qt = QtLayerList()
+        self._qt = QtLayerPanel(self)
         self._viewer = None
         self.total = 0
         self.events = EmitterGroup(source=self,
@@ -297,7 +297,7 @@ def _add(self, event):
         """Callback when an item is added to set its order and viewer.
         """
         layer = event.item
-        self._qt.insert(event.index, len(self), layer)
+        self._qt.layersList.insert(event.index, len(self), layer)
         layer._order = -len(self)
         layer.viewer = self.viewer
 
@@ -306,7 +306,7 @@ def _remove(self, event):
         and reset its order.
         """
         layer = event.item
-        self._qt.remove(layer)
+        self._qt.layersList.remove(layer)
         layer.viewer = None
         layer._order = 0
 
@@ -316,7 +316,18 @@ def _reorder(self, event):
         """
         for i in range(len(self)):
             self[i]._order = -i
-        self._qt.reorder(self)
+        self._qt.layersList.reorder()
         canvas = self.viewer._canvas
         canvas._draw_order.clear()
         canvas.update()
+
+    def remove_selected(self):
+        """Removes selected items from list.
+        """
+        to_delete = []
+        for i in range(len(self)):
+            if self[i].selected:
+                to_delete.append(i)
+        to_delete.reverse()
+        for i in to_delete:
+            self.pop(i)

gui/elements/qt/__init__.py

@@ -5,7 +5,7 @@
 from PyQt5.QtWidgets import QApplication as QtApplication
 
 from ._viewer import QtViewer
-from ._layerList import QtLayerList
+from ._layerPanel import QtLayerPanel
 from ._controls import QtControls
 from ._imageLayer import QtImageLayer
 from ._markersLayer import QtMarkersLayer

gui/elements/qt/_layer.py

@@ -6,7 +6,6 @@
 
 dir_path = dirname(realpath(__file__))
 path_on = join(dir_path,'icons','eye_on.png')
-path_off = join(dir_path,'icons','eye_off.png')
 
 class QtLayer(QFrame):
     def __init__(self, layer):
@@ -110,7 +109,15 @@ def mouseMoveEvent(self, event):
         drag = QDrag(self)
         drag.setMimeData(mimeData)
         drag.setHotSpot(event.pos() - self.rect().topLeft())
-        dropAction = drag.exec_(Qt.MoveAction)
+        dropAction = drag.exec_(Qt.MoveAction | Qt.CopyAction)
+
+        if dropAction == Qt.CopyAction:
+            if not self.layer.selected:
+                index = self.layer.viewer.layers.index(self.layer)
+                self.layer.viewer.layers.pop(index)
+            else:
+                self.layer.viewer.layers.remove_selected()
+
 
     def unselectAll(self):
         if self.layer.viewer is not None:

gui/elements/qt/_layerList.py

@@ -2,10 +2,14 @@
 from PyQt5.QtWidgets import QWidget, QVBoxLayout, QScrollArea
 from ._layerDivider import QtDivider
 
+import weakref
+
+
 class QtLayerList(QScrollArea):
-    def __init__(self):
+    def __init__(self, layers):
         super().__init__()
 
+        self.layers = weakref.proxy(layers)
         self.setWidgetResizable(True)
         #self.setFixedWidth(315)
         self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
@@ -15,6 +19,7 @@ def __init__(self):
         self.layersLayout.addWidget(QtDivider())
         self.layersLayout.addStretch(1)
         self.setAcceptDrops(True)
+        self.setToolTip('Layer list')
 
     def insert(self, index, total, layer):
         """Inserts a layer widget at a specific index
@@ -36,14 +41,14 @@ def remove(self, layer):
             divider.deleteLater()
             divider = None
 
-    def reorder(self, layerList):
+    def reorder(self):
         """Reorders list of layer widgets by looping through all
         widgets in list sequentially removing them and inserting
         them into the correct place in final list.
         """
-        total = len(layerList)
+        total = len(self.layers)
         for i in range(total):
-            layer = layerList[i]
+            layer = self.layers[i]
             if layer._qt is not None:
                 index = self.layersLayout.indexOf(layer._qt)
                 divider = self.layersLayout.itemAt(index+1).widget()
@@ -55,7 +60,8 @@ def reorder(self, layerList):
     def mouseReleaseEvent(self, event):
         """Unselects all layer widgets
         """
-        self.layersLayout.itemAt(1).widget().unselectAll()
+        if self.layersLayout.count() > 1:
+            self.layersLayout.itemAt(1).widget().unselectAll()
 
     def dragLeaveEvent(self, event):
         event.ignore()

gui/elements/qt/_layerPanel.py

@@ -0,0 +1,64 @@
+from PyQt5.QtCore import Qt
+from PyQt5.QtGui import QIcon
+from PyQt5.QtWidgets import QWidget, QVBoxLayout, QHBoxLayout, QPushButton, QFrame
+from ._layerList import QtLayerList
+from os.path import dirname, join, realpath
+import weakref
+
+dir_path = dirname(realpath(__file__))
+path_delete = join(dir_path,'icons','delete.png')
+
+class QtLayerPanel(QWidget):
+    def __init__(self, layers):
+        super().__init__()
+
+        layout = QVBoxLayout()
+        self.layersList = QtLayerList(layers)
+        self.layersControls = QtLayerControls(layers)
+        layout.addWidget(self.layersControls)
+        layout.addWidget(self.layersList)
+        self.setLayout(layout)
+
+class QDeleteButton(QPushButton):
+    def __init__(self, layers):
+        super().__init__()
+
+        self.layers = weakref.proxy(layers)
+
+        self.setIcon(QIcon(path_delete))
+        self.setFixedWidth(28)
+        self.setFixedHeight(28)
+        self.setToolTip('Delete layers')
+        self.clicked.connect(self.on_click)
+        self.setAcceptDrops(True)
+        styleSheet = """QPushButton {background-color:lightGray; border-radius: 3px;}
+            QPushButton:pressed {background-color:rgb(71,143,205); border-radius: 3px;}
+            QPushButton:hover {background-color:rgb(71,143,205); border-radius: 3px;}"""
+        self.setStyleSheet(styleSheet)
+
+    def on_click(self):
+        self.layers.remove_selected()
+
+    def dragEnterEvent(self, event):
+        event.accept()
+        self.hover = True
+        self.update()
+
+    def dragLeaveEvent(self, event):
+        event.ignore()
+        self.hover = False
+        self.update()
+
+    def dropEvent(self, event):
+        event.setDropAction(Qt.CopyAction)
+        event.accept()
+
+class QtLayerControls(QFrame):
+    def __init__(self, layers):
+        super().__init__()
+
+        layout = QHBoxLayout()
+        layout.addWidget(QDeleteButton(layers))
+        layout.addStretch(0)
+
+        self.setLayout(layout)