How to convert String to List (Android)?

Question

I tried to use a Toast to display List<DataItem>.toString(), but the toast only shows [{name='phone',value='081345678912'}] , and does not show all the data that I want.

I want it to show this:

[{name='email',value='akuganteng@gmail.com'}, {name='userpwd',value='123456'}, {name='userid',value='Aku Ganteng'}, {name='phone',value='081345678912'}]

Toast List<DataItem> :

List<DataItem> dataItemList = new ArrayList<>();
DataItem dataItem = new DataItem();
dataItem.setName("email");
dataItem.setName("userpwd");
dataItem.setName("userid");
dataItem.setName("phone");
dataItem.setValue(getEmail);
dataItem.setValue(getPassword);
dataItem.setValue(getFullName);
dataItem.setValue(getPhoneNumber);
dataItemList.add(dataItem);

Toast.makeText(this, dataItemList.toString(), Toast.LENGTH_SHORT).show();

POJO DataItem :

public class DataItem{

    @SerializedName("name")
    private String name;

    @SerializedName("value")
    private String value;

    public void setName(String name){
        this.name = name;
    }

    public String getName(){
        return name;
    }

    public void setValue(String value){
        this.value = value;
    }

    public String getValue(){
        return value;
    }

    @Override
    public String toString(){
        return 
            "{" + 
            "name = '" + name + '\'' + 
            ",value = '" + value + '\'' + 
            "}";
    }
}

score 2 · Accepted Answer · answered Aug 08 '20 at 05:34

The List that you have initialized contains only a single DataItem element whose values are being replaced. To achieve what you have described, you need a DataItem for each of the required data as follows --

List<DataItem> dataItemList = new ArrayList<>();

// email Data Item
DataItem emailDataItem = new DataItem();
emailDataItem.setName("email");
emailDataItem.setValue(getEmail);
dataItemList.add(emailDataItem);

// userpwd Data Item
DataItem userpwdDataItem = new DataItem();
userpwdDataItem.setName("userpwd");
userpwdDataItem.setValue(getPassword);
dataItemList.add(userpwdDataItem);

// userid Data Item
DataItem useridDataItem = new DataItem();
useridDataItem.setName("userid");
useridDataItem.setValue(getFullName);
dataItemList.add(useridDataItem);

// phone Data Item
DataItem phoneDataItem = new DataItem();
phoneDataItem.setName("phone");
phoneDataItem.setValue(getPhoneNumber);
dataItemList.add(phoneDataItem);

Toast.makeText(this, dataItemList.toString(), Toast.LENGTH_SHORT).show();

score 1 · Answer 2 · answered Aug 08 '20 at 05:39

Your DataItem contains a single String name and a single String value. So when you use the same DataItem instance (DataItem dataItem = new DataItem();) all you're doing is overwriting name and value until the last combination are the only values left (phone and the phone number).

Since all these values belong in a single group, I'd recommend redesigning your class to be a more accurate model of your data. First, rename your DataItem class to be more descriptive (like User). Then, within that User class, create instance members and getters/setters for:

private String email;
private String userPassword; // I don't like this though, read below**
private String userId;
private String phoneNumber;

// add getters and setters here

Now you can set each of these properties directly on a single instance of User:

user.setEmail(someEmail);
user.setUserPassword(somePassword);
user.setUserId(someUserId);
user.setPhoneNumber(somePhoneNumber);

** I'd recommend you read up on better ways to store passwords in memory though. See this Stack Overflow question and its answers for more details.

How to convert String to List (Android)?

2 Answers2