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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