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Screens & Dashboards

Hands-on2 exercises

Entity Screens

Screens define what users see when they click on an entity. Every entity type needs a screen with two parts:

Section	Purpose	Shows
`listSettings`	Entity list page	All devices in a table
`detailsSettings`	Entity detail page	One device with charts + children

screens:
  - entityType: my_ext:device
    listSettings:
      layout:
        autoGenerate: false
        cards:
          - key: device_list
            type: ENTITIES_LIST
    detailsSettings:
      staticContent:
        showProblems: true
        showProperties: true
      layout:
        autoGenerate: false
        cards:
          - key: overview_charts
            type: CHART_GROUP
          - key: interface_list
            type: ENTITIES_LIST

Chart Cards

Define charts in chartsCards: — referenced by key from the layout:

chartsCards:
  - key: overview_charts
    displayName: Overview
    charts:
      - displayName: CPU Usage
        visualizationType: GRAPH_CHART
        graphChartConfig:
          metrics:
            - metricSelector: my_ext.cpu:splitBy("dt.entity.my_ext:device")

⚠️ Always include :splitBy("dt.entity.TYPE") in metricSelector — without it, charts show nothing.

Visualization Types

Type	Best For	Config Key
`GRAPH_CHART`	Time series (CPU, traffic, errors over time)	`graphChartConfig`
`SINGLE_VALUE`	Current value (uptime, status)	`singleValueConfig`
`TABLE`	Tabular data (top-N lists)	`tableChartConfig`

🛠 Try it

Add a SINGLE_VALUE chart for sysUpTime to the chartsCards. Use metricSelector com.dynatrace.extension.screen-lab.sysuptime:splitBy("dt.entity.screen_lab:device").

extension.yamlYAML

Entity List Cards

Show child entities on the parent detail page:

entitiesListCards:
  - key: interface_list
    pageSize: 10
    displayName: Interfaces
    entitySelectorTemplate: type(my_ext:interface),fromRelationships.isChildOf($(entityConditions))
    charts:
      - displayName: Traffic
        visualizationType: GRAPH_CHART
        graphChartConfig:
          metrics:
            - metricSelector: "my_ext.if.in.octets.count:splitBy()"

💡 $(entityConditions) is a magic variable — Dynatrace replaces it with the current entity's selector. Adding charts: shows inline sparklines per child row.

Card Type Reference

Card Type	References	Used In
`CHART_GROUP`	`chartsCards` by key	Detail page
`ENTITIES_LIST`	`entitiesListCards` by key	List page or detail page
`INJECTIONS`	Built-in Dynatrace cards	Detail page

🛠 Try itExercise 2

Add an entitiesListCards entry to show child interfaces on the device page. Use fromRelationships.isChildOf($(entityConditions)).

extension.yamlYAML

What's Next

Module 7 — Calculated metrics with func: — compute uptime in hours, memory percentage, bandwidth utilization without writing code.

← PreviousTopology: Entities & RelationshipsNext →Calculated Metrics (func:)