using checkablecombobox for selecting single band rasters

MergeBandTableWidget.py

+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    BandTableWidget.py
+    ---------------------
+    Date                 : 2021-09-14
+    Copyright            : (C) 2021 by J. Pierson, UMR 6554 LETG, CNRS
+    Email                : julie.pierson@univ-brest.fr
+    Based upon           : ReliefColorsWidget.py (C) 2016 by Alexander Bruy
+***************************************************************************
+*                                                                         *
+*   This program is free software; you can redistribute it and/or modify  *
+*   it under the terms of the GNU General Public License as published by  *
+*   the Free Software Foundation; either version 2 of the License, or     *
+*   (at your option) any later version.                                   *
+*                                                                         *
+***************************************************************************
+"""
+
+__author__ = 'J. Pierson, UMR 6554 LETG, CNRS'
+__date__ = '2021-09-14'
+__copyright__ = '(C) 2021 by J. Pierson, UMR 6554 LETG, CNRS'
+
+import os
+
+from qgis.PyQt import uic
+from qgis.PyQt.QtCore import pyqtSlot
+from qgis.PyQt.QtWidgets import (QTreeWidgetItem,
+                                 QMessageBox,
+                                 QInputDialog,
+                                 )
+from qgis.core import (QgsApplication, 
+                       QgsProject,
+                       QgsMapLayer,
+                       QgsProcessing,
+                       QgsMapLayerProxyModel)
+from processing.gui.wrappers import WidgetWrapper
+from osgeo import gdal
+
+pluginPath = os.path.dirname(__file__)
+WIDGET, BASE = uic.loadUiType(os.path.join(pluginPath, 'mergebandtablewidgetbase.ui'))
+
+
+class MergeBandTableWidget(BASE, WIDGET):
+
+    def __init__(self):
+        super(MergeBandTableWidget, self).__init__(None)
+        self.setupUi(self)
+        
+        #self.multiLayers.setLayerType(QgsProcessing.TypeRaster) # 3 for TypeRaster
+        self.multiLayers.checkedItemsChanged.connect(self.layersChanged)
+        self.btnUp.setIcon(QgsApplication.getThemeIcon('/mActionArrowUp.svg'))
+        self.btnDown.setIcon(QgsApplication.getThemeIcon('/mActionArrowDown.svg'))
+        self.layer = None
+        
+        # when alg is launched by user, populate combobox with loaded raster layers
+        self.populateMultiLayers()
+        
+        # this is how to display a message for debugging
+        #QMessageBox.information(None, self.tr('window name'), self.tr('message'))
+     
+    # populate checkable combobox with every loaded single band raster layer
+    def populateMultiLayers(self):
+        # get a list of loaded raster layers
+        layerList = QgsProject.instance().mapLayers().values()
+        rasterList = [i for i in list(layerList) if i.type() == QgsMapLayer.RasterLayer]
+        # keep only single band rasters in list
+        rasterNames = [i.name() for i in list(rasterList) if i.bandCount() == 1]
+        # populate combobox
+        for r in rasterNames:
+            self.multiLayers.addItem(r)
+    
+    # when user changes selected layer in combobox
+    def layersChanged(self):
+        # remove table content
+        self._removeBandData()
+        # get raster layers
+        rasterNames = self.multiLayers.checkedItems()
+        # if there is at least one selected raster
+        if len(rasterNames) != 0:
+            for r in rasterNames:
+                self._addBandData(r)
+#        # if there is one 
+#        if layer != None:
+#            input_raster = gdal.Open(layer.source())
+#            # get number of bands in raster
+#            nbands = input_raster.RasterCount
+#            # for each band
+#            for band_number in range(nbands):
+#                band = input_raster.GetRasterBand(band_number + 1)
+#                # add band number to table
+#                bandnumber = str(band_number+1)
+#                bandname = band.GetDescription()
+#                self._addBandData(bandnumber, bandname)
+    
+    # add selected raster names to table
+    def _addBandData(self, rastername):
+        item = QTreeWidgetItem()
+        item.setText(0, rastername)
+        self.bandClassTree.addTopLevelItem(item)
+    
+    # remove all rows from table    
+    def _removeBandData(self,):
+        self.bandClassTree.clear()
+    
+    # move down selected line in table when down button is clicked
+    @pyqtSlot()
+    def on_btnDown_clicked(self):
+        selectedItems = self.bandClassTree.selectedItems()
+        for item in selectedItems:
+            currentIndex = self.bandClassTree.indexOfTopLevelItem(item)
+            if currentIndex < self.bandClassTree.topLevelItemCount() - 1:
+                self.bandClassTree.takeTopLevelItem(currentIndex)
+                self.bandClassTree.insertTopLevelItem(currentIndex + 1, item)
+                self.bandClassTree.setCurrentItem(item)
+    
+    # move up selected line in table when up button is clicked
+    @pyqtSlot()
+    def on_btnUp_clicked(self):
+        selectedItems = self.bandClassTree.selectedItems()
+        for item in selectedItems:
+            currentIndex = self.bandClassTree.indexOfTopLevelItem(item)
+            if currentIndex > 0:
+                self.bandClassTree.takeTopLevelItem(currentIndex)
+                self.bandClassTree.insertTopLevelItem(currentIndex - 1, item)
+                self.bandClassTree.setCurrentItem(item)
+
+    # when a cell in 2nd column is clicked, open dialog box for entering value
+    @pyqtSlot(QTreeWidgetItem, int)
+    def on_bandClassTree_itemDoubleClicked(self, item, column):
+        if not item:
+            return
+
+        if column == 1:
+            d, ok = QInputDialog.getText(None,
+                                           self.tr('Band name'),
+                                           self.tr('Enter new band name')
+                                           )
+            if ok:
+                item.setText(1, str(d))
+
+    # return table values in a list, one element for each row
+    # [['band 1', 'old name 1', 'new name 1'], ['band 2', 'old name 2', 'new name 2']]
+    def bandNames(self):
+        band_names = []
+        for i in range(self.bandClassTree.topLevelItemCount()):
+            item = self.bandClassTree.topLevelItem(i)
+            if item:
+                row = [item.text(0), item.text(1), item.text(2)]
+                band_names.append(row)
+        return band_names
+
+    def setLayers(self, layers):
+        self.layers = layers
+        self.updateTable(layers)
+        
+    def updateTable(self, layers):
+        item = QTreeWidgetItem()
+        item.setText(0, '0.00')
+        item.setText(1, '0.00')
+        self.bandClassTree.addTopLevelItem(item)
+
+    def setValue(self, value):
+        self.bandClassTree.clear()
+        param = value.split(';')
+        # setting input layer
+        layer_name = param[0]
+#        # if layer is loaded in project
+#        if QgsProject.instance().mapLayersByName(layer_name):
+#            layer = QgsProject.instance().mapLayersByName(layer_name)[0]
+#            self.multiLayers.setLayer(layer)
+#            # setting table values
+#            self.bandClassTree.clear()
+#            rows = param[2:]
+#            for r in rows:
+#                v = r.split(',')
+#                item = QTreeWidgetItem()
+#                item.setText(0, v[0])
+#                item.setText(1, v[1])
+#                item.setText(2, v[2])
+#                self.bandClassTree.addTopLevelItem(item)
+
+    # return a list where 1st element is input raster path
+    # and then each element for a table row
+    def value(self):
+        # adding input layer names to values (useful to select again this layer when using toolbox history)
+        allValues = self.multiLayers.currentLayer().name()
+        allValues += ';'
+        # adding input layer path to values
+        allValues += self.multiLayers.currentLayer().source()
+        allValues += ';'
+        # adding table content to values
+        for b in self.bandNames():
+            allValues += '{0},{1},{2};'.format(b[0], b[1], b[2])
+        return allValues[:-1]
+
+
+class MergeBandTableWidgetWrapper(WidgetWrapper):
+
+    def createWidget(self):
+        return MergeBandTableWidget()
+
+    def postInitialize(self, wrappers):
+        for wrapper in wrappers:
+            if wrapper.param.name == self.param.parent:
+                self.setLayer(wrapper.value())
+                wrapper.widgetValueHasChanged.connect(self.parentValueChanged)
+                break
+
+    def parentValueChanged(self, wrapper):
+        self.setLayer(wrapper.parameterValue())
+
+    def setLayer(self, layer):
+        if isinstance(layer, QgsMapLayer):
+            layer = layer.source()
+        self.widget.setLayer(layer)
+        self.widget.updateTable(layer)
+
+    def setValue(self, value):
+        self.widget.setValue(value)
+
+    def value(self):
+        return self.widget.value()

mergebandtablewidgetbase.ui

+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>Form</class>
+ <widget class="QWidget" name="Form">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>505</width>
+    <height>209</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string notr="true">Form</string>
+  </property>
+  <layout class="QGridLayout" name="gridLayout">
+   <item row="0" column="0">
+    <widget class="QLabel" name="label_2">
+     <property name="text">
+      <string>Raster layers</string>
+     </property>
+     <property name="buddy">
+      <cstring>multiLayers</cstring>
+     </property>
+    </widget>
+   </item>
+   <item row="0" column="1">
+    <widget class="QgsCheckableComboBox" name="multiLayers">
+     <property name="sizePolicy">
+      <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
+       <horstretch>0</horstretch>
+       <verstretch>0</verstretch>
+      </sizepolicy>
+     </property>
+    </widget>
+   </item>
+   <item row="1" column="0" colspan="2">
+    <widget class="QTreeWidget" name="bandClassTree">
+     <column>
+      <property name="text">
+       <string>Band name</string>
+      </property>
+     </column>
+     <column>
+      <property name="text">
+       <string>Band future name</string>
+      </property>
+     </column>
+    </widget>
+   </item>
+   <item row="1" column="3">
+    <layout class="QVBoxLayout" name="verticalLayout">
+     <item>
+      <widget class="QToolButton" name="btnUp">
+       <property name="toolTip">
+        <string>Move up</string>
+       </property>
+       <property name="text">
+        <string>…</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QToolButton" name="btnDown">
+       <property name="toolTip">
+        <string>Move down</string>
+       </property>
+       <property name="text">
+        <string>…</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <spacer name="verticalSpacer">
+       <property name="orientation">
+        <enum>Qt::Vertical</enum>
+       </property>
+       <property name="sizeHint" stdset="0">
+        <size>
+         <width>20</width>
+         <height>40</height>
+        </size>
+       </property>
+      </spacer>
+     </item>
+    </layout>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>