Method insertFieldAt

packages/blockly/core/inputs/input.ts:93–136

* Inserts a field (or label from string), and all prefix and suffix fields, * at the location of the input's field row. * * @param index The index at which to insert field. * @param field Something to add as a field. * @param opt_name Language-neutral identifier which may used to find

(
    index: number,
    field: string | Field<T>,
    opt_name?: string,
  )

   * @returns The index following the last inserted field.
   */
  insertFieldAt<T>(
    index: number,
    field: string | Field<T>,
    opt_name?: string,
  ): number {
    if (index < 0 || index > this.fieldRow.length) {
      throw Error('index ' + index + ' out of bounds.');
    }
    // Falsy field values don't generate a field, unless the field is an empty
    // string and named.
    if (!field && !(field === '' && opt_name)) {
      return index;
    }

    // Generate a FieldLabel when given a plain text field.
    if (typeof field === 'string') {
      field = fieldRegistry.fromJson({
        type: 'field_label',
        text: field,
      })!;
    }

    field.setSourceBlock(this.sourceBlock);
    if (this.sourceBlock.initialized) this.initField(field);
    field.name = opt_name;
    field.setVisible(this.isVisible());

    if (field.prefixField) {
      // Add any prefix.
      index = this.insertFieldAt(index, field.prefixField);
    }
    // Add the field to the field row.
    this.fieldRow.splice(index, 0, field as Field);
    index++;
    if (field.suffixField) {
      // Add any suffix.
      index = this.insertFieldAt(index, field.suffixField);
    }

    if (this.sourceBlock.rendered) {
      (this.sourceBlock as BlockSvg).queueRender();
    }
    return index;
  }

  /**
   * Remove a field from this input.