Hi! I am working on a project to load account information per criteria in a data table and allow users to select which they want to create a new record for. 

However I am unable to pass the rows selected by the user to the controller. the value is returning as undefined or null. Please help!

Here is my code: 
COMPONENT: 
<aura:component controller = "JMA_SearchforAllChildrenAccounts_Ctr" implements="lightning:availableForFlowActions,force:hasRecordId,lightning:availableForFlowScreens,force:lightningQuickActionWithoutHeader" access="global" >
    <aura:handler name="init" value="{!this}" action="{!c.doInit}"/>
    <aura:attribute name="recordId" type="String" access="global"/>
    <aura:attribute name="AccountList" type="Account[]"/>
    <aura:attribute name="childrenAccount" type="Account[]" access="global" />
    <aura:attribute name="data" type="Object" />
    <aura:attribute name="SelectedAccount" type="Account[]" access = "global"/>
    <aura:attribute name="columns" type="List"/>
        <div class="slds-page-header">
        <div class="slds-page-header__row">
                            <div class="slds-page-header__name-title">
                                <h1>
                                    <span class="slds-page-header__title slds-truncate" title="Rohde Corp - 80,000 Widgets">Select Accounts for Deal Proposal</span>
                                </h1>
                            </div>
                        </div>
                        <p class="slds-page-header__name-meta">   Selected Account</p>
                    </div>
    <lightning:datatable 
                         data="{!v.data}" 
                         columns="{!v.columns}" 
                         keyField="id" 
                         selectedRows="{! v.selectedRows }" 
                         maxRowSelection="{! v.maxRowSelection }" 
                         onrowselection="{! c.updateSelectedText }" />
    <br/>
    <center>
        <lightning:button variant="success" label="Create Deal Proposal" title="Create Deal Proposal" onclick="{!c.handleSelect}"/>        
    </center>
</aura:component>

CONTROLLER:

({
    doInit : function(component, event, helper) {
        var recordId = component.get('v.recordId');
        var action = component.get("c.PullChildrenAccounts");
        action.setParams({
            'recordId': recordId,
            'strObjectName' : 'Account',
            'strFieldSetName' : 'JMA_Deal_Proposal_Lightning_Component'
        });
        action.setCallback(this, function(response){
               var state = response.getState();
        if(state === "SUCCESS"){
            component.set("v.data", response.getReturnValue().lstDataTableData);
            component.set("v.columns", response.getReturnValue().lstDataTableColumns);
            }else if (state === 'ERROR'){
                var errors = response.getError();
                if (errors) {
                    if (errors[0] && errors[0].message) {
                        console.log("Error message: " +
                                    errors[0].message);
                    }
                } else {
                    console.log("Unknown error");
                }
            }else{
                console.log('Something went wrong, Please check with your admin');
            }
        });
        $A.enqueueAction(action);
    },
     
    
    updateSelectedText : function(component, event, helper){
        var selectedRows = event.getParam('selectedRows');
        console.log('selectedRows'+selectedRows);
        component.set("v.selectedRowsCount" ,selectedRows.length );
        var rowCount = component.get("v.selectedRowsCount");
        console.log('rowCount'+rowCount);
        let obj =[] ; 
        for (var i = 0; i < selectedRows.length; i++){
            
            obj.push({Name:selectedRows[i].Name});
            
        }
        component.set("v.selectedRowsDetails" ,JSON.stringify(obj) );
        component.set("v.selectedRowsList" ,event.getParam('selectedRows') );
        console.log('obj: '+obj);
    },
    
    handleSelect: function (component, event, helper) {

        var arr = component.get('v.data');
        var obj =  component.get("v.selectedRowsList");
        var rowCount = component.get("v.selectedRowsCount");
        console.log('rowCount'+rowCount);
        console.log('obj '+JSON.stringify(obj) );
        var updateAction = component.get("c.SelectedAccounts");
        updateAction.setParams({ AccountList: obj});
        updateAction.setCallback(this, function(a) {
            $A.get('e.force:refreshView').fire();
        });
        $A.enqueueAction(updateAction);
       
       
    },
    
})