Creating a Custom Filter in ag-Grid

To create a custom filter in ag-Grid, you need to implement a custom filter component.

Here are the general steps to create a custom filter:

1. Create the Custom Filter Component: Create a new component that extends the BaseFilter class provided by ag-Grid. This component will define the custom filter logic and UI.

import { Component } from 'ag-grid-community';
 
export class CustomFilterComponent extends Component {
 
  // Implement the necessary methods and properties for the custom filter
 
  // Constructor
  constructor() {
    super();
    this.template = `
      <div>
        <!-- Custom filter UI goes here -->
      </div>
    `;
  }
 
  // Mandatory method to get the current filter model
  doesFilterPass(params) {
    // Implement your custom filter logic here
  }
 
  // Mandatory method to get the filter model
  getModel() {
    // Return the filter model based on the current state of your custom filter UI
  }
 
  // Mandatory method to set the filter model
  setModel(model) {
    // Apply the filter model to your custom filter UI
  }
 
  // Mandatory method to get the filter's UI component
  getGui() {
    return this.template;
  }
 
  // Optional: implement other necessary methods and events as needed for your custom filter
}

2. Register the Custom Filter Component: To use the custom filter, you need to register it with ag-Grid using the components property in the grid options. Specify the column definition for which you want to apply the custom filter and set its filter property to the registered custom filter component.

const gridOptions = {
  // Other grid options...
  components: {
    customFilter: CustomFilterComponent,
  },
  columnDefs: [
    {
      headerName: 'Column Name',
      field: 'fieldName',
      filter: 'customFilter', // Use the registered custom filter component
    },
    // Other column definitions...
  ],
  // Rest of the grid configuration...
};

3. Implement the Custom Filter Logic: Inside your custom filter component, implement the necessary methods (doesFilterPass, getModel, setModel) based on your filtering requirements. These methods will define the filter logic and handle the filter's model.

The doesFilterPass(params) method is responsible for determining if a row should be filtered out based on the filter's criteria. It takes a params object that provides access to the row's data and other contextual information.

The getModel() method should return the current filter model, representing the state of your custom filter UI.

The setModel(model) method receives the filter model and should update your custom filter UI accordingly.

Additional methods and events can be implemented as needed for your specific custom filter functionality.

Remember to import the necessary ag-Grid modules and dependencies in your custom filter component file.

By following these steps, you can create a custom filter component in ag-Grid and use it to filter data based on your specific requirements.