How to Scroll a list to perform an iteration flow of app using appium?

i need to perform a large list of account closing.The list of 200 accounts which is available as a drop down.only 6 accounts will be available on screen at a time ,for others need to scroll down.How can i perform it using Appium scripting. The flow i tried and sample source code i tried is given below

package *****;
        import java.util.List;
        import io.appium.java_client.MobileBy;
        import io.appium.java_client.android.AndroidElement;
        import org.openqa.selenium.By;
        import org.openqa.selenium.WebElement;
        import org.openqa.selenium.support.ui.ExpectedConditions;
        import org.openqa.selenium.support.ui.WebDriverWait;
        import org.testng.annotations.Test;


        public class QuickPay extends **** {            

         @Test
                     public void T1a_Landingpage() {

        //AAD Closing starts

        //Enter pin for login to the app
driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-button-1')]")).sendKeys("1111");


        //Click on main menu    
                 driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-tab-5')]")).click();



                         for(int i=1;i<10;i++){
                             driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-button-18')]")).click();                    

        //click on drop down which list 200 account numbers                          driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-input-5')]")).click();

        //Click on first account from the list           driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-simplelistitem-"+i+"')]")).click();                         

        //Click on proceed button                    driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-input-6')]")).click();
                             driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-simplelistitem-3')]")).click();                     
                             driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-button-30')]")).click();                    
                             driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-button-31')]")).click();                    
                             driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-button-37') and @index='1']")).click();    
                             driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-button-37') and @index='1']")).click();
                             driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-button-37') and @index='1']")).click();
                             driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-button-37') and @index='1']")).click();
                             driver.findElement(By.xpath("//android.view.View[contains(@resource-id,'ext-button-49')]")).click();

                         }
                        //AAD Closing Ends
        }

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