How to detect drill mode

Hi alexpokerface,

Unfortunately there's no simple method to check this. I think the only way to detect this would be to check the dataView.metadata for the presence of drillableRoles, and perhaps, based on your knowledge of your setup, whether the resulting state means you're somewhere in the hierarchy (e.g, if there's no DrillType.Up available on a role, then you are at the top of your hierarchy, and therefore you aren't in a drill state.

The pattern for interrogation of drill state here in the docs may provide a starting point for you.

Good luck,

Daniel

Hi Alex, alexpokerface 

Yes, you can detect drill mode in custom visuals.

How it works:

When a user clicks "Drill Down" in Power BI, the visual gets a new update call. In that update, Power BI tells your visual what mode it's currently in through the DataView metadata.

The Code:

Put this inside your `update(options: VisualUpdateOptions)` method:

```typescript
import { DrillState } from "powerbi-visuals-api";

public update(options: VisualUpdateOptions) {
const dataView = options.dataViews?.[0];

if (!dataView) return;

const drillState = dataView.metadata?.drillState;

switch(drillState) {
case DrillState.DrillDown:
// User clicked Drill Down on a category
// Example: Year -> Quarter -> Month
this.renderDrillView(dataView);
break;

case DrillState.Expand:
// User clicked + icon to expand tree
this.renderExpandedView(dataView);
break;

case DrillState.None:
default:
// Normal selection mode

I hope you got the answer is any problem you can freely to ask here , Thanks 😊

Hi alexpokerface ,
As dm-p said there is no simple straight forward method to check this. However, you can do try the following, all inside update():

1. dataView.metadata.dataRoles.drillableRoles — a map of role name → the DrillType[] currently available for it. When Drill Up is available for a role, the user has drilled down at least one level, which is the reliable "am I in a drilled-down state" signal:

import powerbi from "powerbi-visuals-api";
import DrillType = powerbi.DrillType;

public update(options: powerbi.extensibility.visual.VisualUpdateOptions😞 void {
    const dataRoles = options.dataViews?.[0]?.metadata?.dataRoles;
    const available = dataRoles?.drillableRoles?.["category"] ?? []; // role name from capabilities "drilldown".roles

    const isDrilledDown = available.indexOf(DrillType.Up) >= 0;   // Drill Up exists => below the top level
    const canDrillDown  = available.indexOf(DrillType.Down) >= 0; // more levels below
    const drillDisabled = dataRoles?.isDrillDisabled === true;    // drilling currently turned off
}

2. After any drill, Power BI just calls update() again with a new DataView. Read the level from the data — categorical: the number of categorical.categories and each categories[i].source.displayName (e.g., Year → Quarter → Month); matrix: the depth of matrix.rows.levels and each node's level. Note the category value type can change per level (Date at the top, string lower down), so guard with categories[i].source.type before parsing.

3. To drive drilling from your own UX (e.g., double-click to drill down), call host.drill(args) (API 4.7.0+), and optionally host.setCanDrill(true/false) (5.7.0+) to enable/disable it at runtime.

Good luck,
Asaf.

References

• The Drilldown API in Power BI visuals — documents the exact drillableRoles['...'].indexOf(powerbi.DrillType.Down) pattern and host.drill()
• Add drill-down support in Power BI visuals
• The dynamic drill-down API in Power BI visuals