Adds helper functions and EndChecks to lessons

vector_layers_attributes/Edit_multiple_features_attributes/02_select_features_to_update.md

@@ -24,4 +24,7 @@ All selected buildings will be rendered in bright yellow.
 
 ![buildings_are_selected](buildings_are_selected.png)
 
+If necessary, click **Solve Step** to automatically select the block's
+buildings.
+
 Click **Next step** once you are done.

vector_layers_attributes/Edit_multiple_features_attributes/functions.py

@@ -1,7 +1,19 @@
 from lessons.utils import layerFromName
+from qgis.core import QgsMapLayer, QgsRectangle
 
 # Functions
 
+def selectByRectangle(layername, xmin, ymin, xmax, ymax):
+    """
+    Select features in rectangle
+    :param layername: Layer's name as in the layers panel
+    :return: None
+    """
+
+    layer = layerFromName(layername)
+    if layer is not None and layer.type() == QgsMapLayer.VectorLayer:
+        layer.selectByRect(QgsRectangle(xmin, ymin, xmax, ymax))
+
 # EndCheck Function
 
 def isLayerEditable(*args):
@@ -10,3 +22,40 @@ def isLayerEditable(*args):
     """
     layer = layerFromName(args[0])
     return layer is not None and layer.isEditable()
+
+def isLayerSaved(layername):
+    """
+    Returns True if no changes were made in the layer after the last save
+    :param layername: Layer name as in the layers panel
+    :return: Boolean
+    """
+
+    layer = layerFromName(layername)
+    return layer is not None and layer.type() == QgsMapLayer.VectorLayer and \
+           not layer.isModified()
+
+def checkFieldValue(layername, field, value):
+    """
+    Return True if all features have a certain value for a
+    particular field. If the layer has selected features, only those will be
+    taken in account
+    :param layername: Layer's name as in the layers panel
+    :param field: Field name
+    :param value: value to confirm
+    :return: Boolean
+    """
+
+    layer = layerFromName(layername)
+    if layer is None:
+        return False
+
+    if layer.selectedFeatureCount():
+        features = layer.selectedFeatures()
+    else:
+        features = layer.getFeatures()
+
+    for feature in features:
+        if feature.attribute(field) != value:
+            return False
+
+    return True

vector_layers_attributes/Edit_multiple_features_attributes/lesson.yaml

@@ -6,17 +6,30 @@ lesson:
     steps:
     - description: 01_introduction.md
       name: Introduction
+
     - description: 02_select_features_to_update.md
       name: Select features to update
+
+      function:
+        name: selectByRectangle
+        params:
+          - Buildings
+          - 2108266.086
+          - 736866.556
+          - 2108698.209
+          - 737332.511
+
     - description: 03_open_attribute_table.md
       name: Open attribute table
+
     - description: 04_turn_layer_into_editing_mode.md
       name: Turn layer into editing mode
 
       endcheck:
         name: isLayerEditable
         params:
           - Buildings
+
     - description: 05_update_a_field_of_the_selected_features.md
       name: Update a field of the selected features
 
@@ -26,18 +39,58 @@ lesson:
         - QgsFieldCalculatorBase
         - 300
         - 1000
+
+      endcheck:
+        name: checkFieldValue
+        params:
+          - Buildings
+          - DESCRIPTIO
+          - UNDER CONSTRUCTION
+
     - description: 06_confirm_the_changes.md
       name: Confirm the changes
+
     - description: 07_change_multiple_features_attributes_using_the_quick_bar.md
       name: Change multiple features attributes using the quick bar
+
+      endcheck:
+        name: checkFieldValue
+        params:
+          - Buildings
+          - UPDATE_DAT
+          - 2017-08-15
+
     - description: 08_edit_multiple_fields_using_multi_edit_mode.md
       name: Edit multiple fields using multi edit mode
+
+      endcheck:
+        name: checkFieldValue
+        params:
+          - Buildings
+          - UPDATE_DAT
+          - 2017-09-24
+
+      endcheck:
+        name: checkFieldValue
+        params:
+          - Buildings
+          - DESCRIPTIO
+          - COMMERCIAL
+
     - description: 09_confirm_multiple_field_changes.md
       name: Confirm multiple field changes
+
     - description: 10_save_changes_to_the_attributes.md
       name: Save changes to the attributes
+
+      endcheck:
+        name: isLayerSaved
+        params:
+          - Buildings
+
     - description: 11_turn_editing_mode_off.md
       name: Turn editing mode off
+
     nextLessons:
     - group: Vector layer attributes
       name: 09. Join attribute tables

vector_layers_attributes/Edit_multiple_features_attributes/project.qgs

@@ -5,24 +5,24 @@
   <evaluateDefaultValues active="0"/>
   <layer-tree-group expanded="1" checked="Qt::Checked" name="">
     <customproperties/>
-    <layer-tree-layer expanded="1" providerKey="ogr" checked="Qt::Checked" id="raleigh_downtown20161228143332835" source="E:/boundless/repos/desktop-lessons/vector_layers_attributes/Edit multiple features attributes/data/raleigh_downtown.shp" name="Raleigh downtown">
+    <layer-tree-layer expanded="1" providerKey="ogr" checked="Qt::Checked" id="raleigh_downtown20161228143332835" source="E:/boundless/repos/desktop-lessons/vector_layers_attributes/Edit_multiple_features_attributes/data/raleigh_downtown.shp" name="Raleigh downtown">
       <customproperties/>
     </layer-tree-layer>
-    <layer-tree-layer expanded="1" providerKey="ogr" checked="Qt::Checked" id="raleigh_downtown_streets20161228143254740" source="E:/boundless/repos/desktop-lessons/vector_layers_attributes/Edit multiple features attributes/data/raleigh_downtown_streets.shp" name="Streets">
+    <layer-tree-layer expanded="1" providerKey="ogr" checked="Qt::Checked" id="raleigh_downtown_streets20161228143254740" source="E:/boundless/repos/desktop-lessons/vector_layers_attributes/Edit_multiple_features_attributes/data/raleigh_downtown_streets.shp" name="Streets">
       <customproperties/>
     </layer-tree-layer>
-    <layer-tree-layer expanded="1" providerKey="ogr" checked="Qt::Checked" id="raleigh_downtown_buildings20170320122317569" source="E:/boundless/repos/desktop-lessons/vector_layers_attributes/Edit multiple features attributes/data/raleigh_downtown_buildings.shp" name="Buildings">
+    <layer-tree-layer expanded="1" providerKey="ogr" checked="Qt::Checked" id="raleigh_downtown_buildings20170320122317569" source="E:/boundless/repos/desktop-lessons/vector_layers_attributes/Edit_multiple_features_attributes/data/raleigh_downtown_buildings.shp" name="Buildings">
       <customproperties/>
     </layer-tree-layer>
   </layer-tree-group>
   <relations/>
   <mapcanvas>
     <units>feet</units>
     <extent>
-      <xmin>2108538.56693823775276542</xmin>
-      <ymin>736499.42365499236620963</ymin>
-      <xmax>2109218.90961974998936057</xmax>
-      <ymax>737517.45137102552689612</ymax>
+      <xmin>2108153.50982284685596824</xmin>
+      <ymin>736582.06148340972140431</ymin>
+      <xmax>2108833.85250435909256339</xmax>
+      <ymax>737600.08919944288209081</ymax>
     </extent>
     <rotation>0</rotation>
     <projections>1</projections>
@@ -201,7 +201,7 @@
       <customproperties/>
     </Composition>
   </Composer>
-  <Composer title="A4 portrait" visible="1">
+  <Composer title="A4 portrait" visible="0">
     <Composition resizeToContentsMarginLeft="0" snapping="0" showPages="1" guidesVisible="1" resizeToContentsMarginTop="0" worldFileMap="" alignmentSnap="1" printResolution="300" paperWidth="210" gridVisible="0" snapGridOffsetX="0" smartGuides="1" snapGridOffsetY="0" resizeToContentsMarginRight="0" snapTolerancePixels="5" printAsRaster="0" generateWorldFile="0" paperHeight="297" numPages="1" snapGridResolution="10" resizeToContentsMarginBottom="0">
       <symbol alpha="1" clip_to_extent="1" type="fill" name="">
         <layer pass="0" class="SimpleFill" locked="0">
@@ -254,7 +254,7 @@
             <styleFont description="Ubuntu,12,-1,5,50,0,0,0,0,0" style=""/>
           </style>
         </styles>
-        <ComposerItem pagey="222.915" page="1" id="" lastValidViewScaleFactor="-1" positionMode="0" positionLock="false" x="16.1386" y="222.915" visibility="1" zValue="2" background="true" transparency="0" frameJoinStyle="miter" blendMode="0" width="177.723" outlineWidth="0.3" excludeFromExports="0" uuid="{5aa84e88-5af7-4adf-a9e4-2f84832130bc}" height="61.1" itemRotation="0" frame="false" pagex="16.1386">
+        <ComposerItem pagey="222.915" page="1" id="" lastValidViewScaleFactor="-1" positionMode="0" positionLock="false" x="16.1386" y="222.915" visibility="1" zValue="2" background="true" transparency="0" frameJoinStyle="miter" blendMode="0" width="127.5" outlineWidth="0.3" excludeFromExports="0" uuid="{5aa84e88-5af7-4adf-a9e4-2f84832130bc}" height="55.9" itemRotation="0" frame="false" pagex="16.1386">
           <FrameColor alpha="255" red="0" blue="0" green="0"/>
           <BackgroundColor alpha="255" red="255" blue="255" green="255"/>
           <customproperties/>
@@ -313,7 +313,7 @@
           <annotationFontProperties description="Ubuntu,11,-1,5,50,0,0,0,0,0" style=""/>
         </ComposerMapGrid>
         <AtlasMap scalingMode="2" atlasDriven="0" margin="0.10000000000000001"/>
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           <customproperties/>