Studies Repository

Repository for storing information about:

• Available indicators for using in the chart.
• Enabled indicators (on the chart).
• Favorites user's indicators.

Repository interface:

/**
* Interface for a repository to store indicators settings data in the library.
*
* Implementation of this class is mandatory for the library to function. It is passed to [com.devexperts.dxcharts.lib.domain.DxChartsConfig].
*
* Standard implementation is [com.devexperts.dxcharts.lib.data.repo.default_repos.DefaultStudiesRepository].
*/
interface StudiesRepository {
  /**
   * Method to get default settings for an indicator by its id.
   */
  fun getDefaultStudySettingsById(id: String): StudiesSetting?
  /**
   * Method to get default settings for all indicators.
   */
  fun getDefaultStudies(): List<StudiesSetting>
  /**
   * Method to get settings for all available indicators.
   */
  fun getAvailableStudies(): List<StudiesSetting>
  /**
   * Method to get settings for favorite indicators.
   */
  fun getFavoritesStudies(): List<StudiesSetting>
  /**
   * Method to get settings for selected (added to the chart) indicators.
   */
  fun getSelectedStudies(): List<StudiesSetting>
  /**
   * Method to toggle an indicator's inclusion in the favorites list.
   */
  fun toggleFavoriteStudy(value: StudiesSetting)
  /**
   * Method to toggle an indicator's inclusion on the chart, adding it to the selected list.
   */
  fun toggleStudy(value: StudiesSetting)
  /**
   * Method to get the settings of an indicator by its id.
   */
  fun findStudyById(id: String): StudiesSetting?
  /**
   * Method to update the settings of an indicator.
   */
  fun updateStudy(study: StudiesSetting)
  /**
   * Method to clear the list of selected indicators, disabling indicators displayed on the chart.
   */
  fun deselectAll()
}

The class com.devexperts.dxcharts.provider.domain.StudiesSetting used in the repository:

/**
* Data class representing the settings for a study in a financial indicator.
*
* @property id The unique identifier for the study setting.
* @property title The title of the study.
* @property uuid The universally unique identifier (UUID) for the study.
* @property type The type of the indicator associated with the study.
* @property parameters The list of parameters for the study.
* @property lines The list of lines for the study.
* @property overlaying A boolean indicating whether the study is overlaying on the chart.
* @property calculateFutureData A boolean indicating whether to calculate future data for the study.
* @property categories A string representing the categories associated with the study.
* @property locked A nullable boolean indicating whether the study is locked.
*/
data class StudiesSetting(
  val id: String,
  val title: String,
  val uuid: String,
  val type: IndicatorType,
  val parameters: List<Parameter>,
  val lines: List<Line>,
  val overlaying: Boolean,
  val calculateFutureData: Boolean,
  val categories: String,
  val locked: Boolean?
) {
  /**
   * Data class representing a line associated with a study.
   *
   * @property title The title of the line.
   * @property type The type of the study line.
   * @property thickness The thickness of the line.
   * @property colors The colors associated with the line, which should be in either rgba format (e.g., "rgba(255, 0, 0, 1)") or hex format (e.g., "#FF0000FF").
   * @property visible A boolean indicating whether the line is visible.
   */
  data class Line(
      val title: String?,
      val type: Type?,
      val thickness: Int?,
      val colors: List<String>?,
      val visible: Boolean?
  ) {
      /**
       * Enum class representing the types of study lines.
       *
       * Values: [POINTS], [LINEAR], [HISTOGRAM], [DIFFERENCE], [ABOVE_CANDLE_TEXT],
       * [TEXT], [BELOW_CANDLE_TEXT], [ABOVE_CANDLE_TRIANGLE], [TRIANGLE],
       * [COLOR_CANDLE], [RECTANGULAR];
       */
      enum class Type {
          POINTS,
          LINEAR,
          HISTOGRAM,
          DIFFERENCE,
          ABOVE_CANDLE_TEXT,
          TEXT,
          BELOW_CANDLE_TEXT,
          ABOVE_CANDLE_TRIANGLE,
          TRIANGLE,
          COLOR_CANDLE,
          RECTANGULAR;
      }
  }
  /**
   * Data class representing a parameter associated with a study.
   *
   * @property id The unique identifier for the parameter.
   * @property type The type of the study parameter.
   * @property value The value of the parameter.
   * @property validation The [Validation] rules for the parameter.
   * @property visible A boolean indicating whether the parameter is visible.
   */
  data class Parameter(
      val id: String,
      val type: Type,
      val value: Any?,
      val validation: Validation?,
      val visible: Boolean?
  ) {
      /**
       * Data class representing validation rules for a study parameter.
       *
       * @property min The minimum value allowed for the parameter.
       * @property max The maximum value allowed for the parameter.
       * @property precision The precision of the parameter value.
       */
      data class Validation(
          val min: Double?,
          val max: Double?,
          val precision: Int?,
      )
      /**
       * Enum class representing the types of study parameters.
       *
       * Values: [INTEGER_RANGE], [DOUBLE_RANGE], [PRICE_FIELD], [STRING], [AGGREGATION], [BOOLEAN], [AVERAGE], [UNDEFINED]
       */
      enum class Type {
          INTEGER_RANGE,
          DOUBLE_RANGE,
          PRICE_FIELD,
          STRING,
          AGGREGATION,
          BOOLEAN,
          AVERAGE,
          UNDEFINED,
      }
  }
}

In the default implementation, it is necessary to pass a list of available indicators.

The loading of indicators for the default implementation is done using com.devexperts.dxcharts.lib.data.implementation.StudiesLoader .