Dynamic & Realtime Data

Available since v1.6.3 - constantly improved.

For adding new data to the chart or removing data dynamically, there are various methods that allow to either add or remove Entry objects to an existing DataSet or DataSet objects to/from an existing ChartData object.

Possibilities of adding / removing data dynamically

Class DataSet (and all subclasses):

• addEntry(Entry e): Adds the given Entry object to the DataSet.

Class ChartData (and all subclasses):

• addEntry(Entry e, int dataSetIndex): Adds the given Entry to the DataSet at the specified dataset index.
• addDataSet(DataSet d): Adds the given DataSet object to the ChartData object.

In addition to that, there are also methods for removing data dynamically.

Class DataSet (and all subclasses):

• public boolean removeFirst(): Removes the first Entry (at index 0) of this DataSet from the entries array. Returns true if successful, false if not.
• public boolean removeLast(): Removes the last Entry (at index size-1) of this DataSet from the entries array. Returns true if successful, false if not.
• public boolean removeEntry(Entry e): Removes the given Entry object from the DataSet. Returns true if successful.
• public boolean removeEntry(int xIndex): Removes the Entry at the given x-index from the DataSet. Returns true if successful.

Class ChartData (and all subclasses):

• public boolean removeEntry(Entry e, int dataSetIndex): Removes the given Entry object from the DataSet with the given dataset index. Returns true if successful.
• public boolean removeEntry(int xIndex, int dataSetIndex): Removes the Entry at the given x-index from the DataSet with the given dataset index. Returns true if successful.
• public boolean removeDataSet(DataSet d): Removes the given DataSet object from the ChartData object. Returns true if successful.
• public boolean removeDataSet(int index): Removes the DataSet at the given index from the ChartData object. Returns true if successful.

Keep in mind

After adding or removing data dynamically, notifyDataSetChanged() must be called on the chart before refreshing it (by calling invalidate()).

 // more code ...
 exampleData.addEntry(...);
 chart.notifyDataSetChanged(); // let the chart know it's data changed
 chart.invalidate(); // refresh

Note: Methods like moveViewTo(...) will automatically call invalidate().

Examples of dynamic data

For examples of how to implement dynamical data adding/removing, please refer the example app and the following example Activities in it:

• DynamicalAddingActivity
• RealtimeDataActivity