Java – how to add data in a list item in Android
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Java
I am a new Android Developer I am developing a sample application I want to add some data to the object list
My mainactivity Java class code:
public class MainActivity extends Activity { private PersonalInfo item; private List<PersonalInfo> itemList = new ArrayList<PersonalInfo>(); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); for (int i = 0; i < 5; i++) { item.setFirstName("AA::" + i); item.setLastName("BB::" + i); item.setAddress("New City " + i); item.setSex("Male"); itemList.add(item); item = new PersonalInfo(); } for(PersonalInfo p:itemList){ System.out.println("First Name::"+p.getFirstName()); System.out.println("Last Name::"+p.getLastName()); } } }
My personalinfo Java class code:
public class PersonalInfo { private String firstName; private String lastName; private String address; private String sex; public String getFirstName() { return firstName; } public void setFirstName(String firstName) { this.firstName = firstName; } public String getLastName() { return lastName; } public void setLastName(String lastName) { this.lastName = lastName; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } }
When I run it, then show the flow error
Thanks for your help.
Solution
Here's the problem:
for (int i = 0; i < 5; i++) { item.setFirstName("AA::" + i); <-- error happened here because item is null item.setLastName("BB::" + i); item.setAddress("New City " + i); item.setSex("Male"); itemList.add(item); item = new PersonalInfo(); }
You need to initialize the project first and then set the data to, so your code must be:
for (int i = 0; i < 5; i++) { item = new PersonalInfo(); <-- I've moved this line item.setFirstName("AA::" + i); item.setLastName("BB::" + i); item.setAddress("New City " + i); item.setSex("Male"); itemList.add(item); }
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