For managing the data of a screen, the CustomScreen provides a simple API which can be accessed via getDataApi('DATA_PROVIDER_NAME') from anywhere in it's extended classes.

This API provides following functions:

• dynamic getValue(String columnName)
  Provides the value of a specific column
• List getValues(List columnNames)
  Provides a list of values for the specified columns
  
• setValue(String columnName, dynamic value)
  Sets the value for a specific column
• setValues(List columnNames, List values)
  Sets the values for a list of specified columns
• insertRecord()
  Inserts a new record
• deleteRecord(int index)
  Deletes the record at the specified index
• selectRecord(int index)
  Selects the record at the specified index

The client persists those changes by itself.

Examples

Reading a value

DataApi dataApi = getDataApi('JVxMobileDemo/Con-CG/contacts#4');
 
FlatButton(
    child: Text("Call"), onPressed: () {
        phone = dataApi.getValue("PHONE");
	launch("tel://$phone");
    })

Setting a value

DataApi dataApi = getDataApi('JVxMobileDemo/Con-CG/contacts#4');
 
FlatButton(
    child: Text("Set phone number"), onPressed: () {
        phone = dataApi.setValue("PHONE", '+43660123456');
    }
)

Inserting a record

DataApi dataApi = getDataApi('JVxMobileDemo/Con-CG/contacts#4');
 
FlatButton(
    child: Text("Insert"), onPressed: () {
        phone = dataApi.insertRecord();
    }
)