Iss 750 filtering

src/.vitepress/sidebar/en.js

@@ -111,6 +111,7 @@ export default {
         { text: 'Synchronisation in Mergin Maps Mobile App', link: '/field/autosync/' },
         { text: 'Measurement Tools', link: '/field/measure/' },
         { text: 'Layers in Mergin Maps Mobile App', link: '/field/layers/' },
+        { text: 'Filtering Features', link: '/field/filtering/' },
         { text: 'Map Sketching', link: '/field/map-sketching/' },
         { text: 'Photo Sketching', link: '/field/photo-sketching/' },
         { text: 'How to Add, Edit, Delete Features', link: '/field/mobile-features/' },

src/field/filtering/index.md

@@ -0,0 +1,76 @@
+---
+description: Add custom filters to sort and display only those features that you need during your field survey.
+---
+
+# Filtering Features in Mergin Maps mobile app
+[[toc]]
+
+Custom filters can be added to the <MobileAppNameShort /> to easily filter features displayed on the map as well as in the [survey layers](../layers/#browsing-features).
+
+## Enable and define filtering in QGIS
+Filters can be enabled and defined in QGIS in **Project Properties**.
+
+::: tip Plugin upgrade
+If you do not see the **Filtering** option in the **Project properties**, check for [plugin upgrades](../../setup/install-mergin-maps-plugin-for-qgis/#plugin-upgrade).
+:::
+
+Check the :heavy_check_mark: **Enable filtering** option in the <MainPlatformName /> tab, click on the **Add filter** button and select a filter type from the list. The list of available [filter types](#filter-types) and their properties can be found below.
+
+Then, define the filter:
+   - **Type** - the filter type (in general, it should match the widget type of the filtered field)
+   - **Layer** - choose from the project's layers
+   - **Field** - choose from the fields of the layer. Only fields with data types compatible with the selected filter type are offered.
+   - **Title** - the name of the filter, which will be displayed in the <MobileAppNameShort />
+
+   ![Filtering in QGIS Mergin Maps project](./qgis-project-properties-enable-filtering.webp "Filtering in QGIS Mergin Maps project")
+
+You can add as many filters as you need by using the **Add filter** button.
+
+The order of filters can be changed by selecting a filter and using the **Up** and **Down** buttons. To remove a filter, select it and click the **Remove** button.
+![Filtering in QGIS Mergin Maps project](./qgis-filtering.webp "Filtering in QGIS Mergin Maps project")
+
+qgis-filtering.webp
+Don't forget to save your project and synchronise changes so that you can use the filters in the <MobileAppNameShort />.
+
+
+### Filter types
+
+**Text** filter uses simple text input. Results are filtered based the SQL expression `"field" ILIKE '%input%'`. Available for text and number field types.
+
+**Number** filter provides *from* and *to* number inputs. Results are filtered based on SQL expression `"field" >= 'input_from' AND "field" <= 'input_to'`. Available for text and number field types.
+
+**Date** filter provides *from* and *to* date (calendar) inputs. Results are filtered based on SQL expression `"field" >= 'input_from' AND "field" <= 'input_to'`. Available for date field types configured with the [Date and time widget](../../layer/date-time/).
+
+**Boolean** filter provides a toggle between *all*, *true* and *false* values. Results are filtered based on SQL expression `"field" == 'input'`. Available for Boolean, text and integer field types configured with the [Checkbox widget](../../layer/checkbox/).
+
+**Single select** filter provides a drop-down menu of field values. One value can be selected at once. The results are filtered based on SQL expression `"field" == 'input'`. Available for text and number field types configured with the [Value map or Value relation widget](../../layer/value-select/).
+
+**Multi select** filter provides a drop-down menu of field values. Multiple values can be selected at once. The results are filtered based on SQL expression `"field" IN ('input')`. Available for text and number field types configured with the [Value map or Value relation widget](../../layer/value-select/#value-relation).
+
+In the <MobileAppNameShort />, the filter types looks as follows:
+
+![Filter types in Mergin Maps mobile app](./mobile-filter-types.webp "Filter types in Mergin Maps mobile app") 
+
+## Filtering features in the mobile app
+Filters defined in [<MainPlatformName /> project in QGIS](#enable-and-define-filtering-in-qgis) can be used in the <MobileAppNameShort />. You can filter features across multiple layers by entering or selecting values in corresponding filters. The filtering affects both the map display and the feature browsing list. 
+
+:::warning Filters reset
+Filters are reset when the project is synced. Also, they do not stay saved when the app is restarted.
+:::
+
+Here is an example of how filtering works:
+
+1. Tap the **Filters** button to open filters defined in the project
+   ![Filtering button in Mergin Maps mobile app](./mobile-open-filters.webp "Filtering button in Mergin Maps mobile app")
+
+2. Enter or select values in the filters. Here, we will use a *Single select* filter on the *trees* layer and select a *tree species* value from the list.
+
+   You can use more filters at once.
+
+   Tap on the **Apply filters** button to confirm the filtering.
+  ![Filtering in Mergin Maps mobile app](./mobile-filter-single-selection.webp "Filtering in Mergin Maps mobile app")
+
+3. With active filters, only features that match the criteria are displayed on the map as well as when [browsing features](../layers/#layers-legend-and-features).
+
+   If filters are applied
+  ![Active filter in Mergin Maps mobile app](./mobile-filtered-features.webp "Active filter in Mergin Maps mobile app")

src/gis/features/index.md

@@ -82,6 +82,8 @@ If the map tip has `# image` marker on the first line, the following line is und
 ## Background layers
 Various online and offline maps can be used as background layers for navigation during the field survey. You can find more information in [Background Maps](../settingup_background_map/).
 
+## Map themes
+[Map Themes](../setup_themes/) make possible to switch between different background maps, combinations of visible layers or their styles both in QGIS and in <MobileAppName />.
 
 ## Project settings
 - Ensure the paths are set to *Relative* in the **General** tab in Project Properties. All paths to the project data in <MobileAppName /> are relative to the project location.
@@ -179,7 +181,9 @@ There is an option to define the order in which layers are displayed in the <Mob
 
 ![Layer order in QGIS Mergin Maps project](./project-layer-order.jpg "Layer order in QGIS Mergin Maps project")
 
-### Map themes
-[Map Themes](../setup_themes/) make possible to switch between different background maps in <MobileAppName /> (e.g. cartography maps and aerial imagery)
+### Filtering features
+Filters for features in the <MobileAppNameShort /> can be enabled in the **<MainPlatformName />** tab in **Project properties**.
 
+![Enable filtering in QGIS Mergin Maps project](./project-filtering.webp "Enable filtering in QGIS Mergin Maps project")
 
+You can find more details about how this works in [Filtering Features](../../field/filtering/).

src/index.md

@@ -105,6 +105,7 @@ The ecosystem consist of various components:
 - [Synchronisation in <MobileAppName />](./field/autosync/)
 - [Measurement Tools](./field/measure/)
 - [Layers in <MobileAppName />](./field/layers/)
+- [Filtering Features in <MobileAppName />](./field/filtering/)
 - [Map Sketching in <MobileAppName />](./field/map-sketching/)
 - [Photo Sketching in <MobileAppName />](./field/photo-sketching/)
 - [How to Add, Edit, Delete Features](./field/mobile-features/)

src/manage/plugin/index.md

@@ -1,5 +1,7 @@
 ---
 description: Create, set up and synchronise your Mergin Maps projects with Mergin Maps QGIS plugin. The plugin brings Mergin Maps functionalities to QGIS.
+
+outline: deep
 ---
 
 # Mergin Maps QGIS Plugin Overview
@@ -98,6 +100,7 @@ Some settings of your [<MainPlatformName /> project](../project/) can be done th
 - Enable [**Map sketching**](../../field/map-sketching/)
 - Set [**Layer order**](../../field/layers/#layer-order) for the <MobileAppNameShort />
 - Enable [**Photo sketching**](../../field/photo-sketching/) to annotate pictures in the <MobileAppNameShort />
+- Enable [**Filtering**](../../field/filtering) features in the <MobileAppNameShort />
 
 ![Mergin Maps Project Properties in QGIS](./qgis-mergin-maps-project-properties.jpg "Mergin Maps Project Properties in QGIS")