---
title: Data Types
slug: docs/android/data-objects/android-data-types
description: In this guide you learn about Datatype of Parse using Android and how to read and save this data.
image: https://www.back4app.com/images/logo-social.png
docTags: 
createdAt: 2024-03-13T12:06:13.306Z
---

# Parse Data Types on Android

## Introduction

In this guide, you will learn about the Parse Datatypes using Android. You will read and save the Parse Objects on Back4App from an Android App.

Storing data on Parse is built around the <font color="#2166ae">`ParseObject`</font>. Each <font color="#2166ae">`ParseObject`</font> contains key-value pairs of JSON-compatible data. This data is schemaless, which means that we don’t need to specify ahead of time what keys exist on each <font color="#2166ae">`ParseObject`</font>. We can set whatever key-value pairs we want, and our backend will store them. For example, let’s say we’re tracking high scores for a game. A single <font color="#2166ae">`ParseObject`</font> could contain:

:::BlockQuote
1   score: 133&#x37;**,** playerName: "Sean Plott"**,** cheatMode: **false**
:::

Keys must be alphanumeric strings, and values can be:

- <font color="#2166ae">`String`</font>=> <font color="#2166ae">`String`</font>
- <font color="#2166ae">`Number`</font>(primitive numeric values such as <font color="#2166ae">`int`</font>,<font color="#2166ae">`double`</font>)
- <font color="#2166ae">`Bool`</font>=> <font color="#2166ae">`boolean`</font>
- <font color="#2166ae">`DateTime`</font>=> java.util.Date
- <font color="#2166ae">`Null`</font>=> JSONObject.NULL
- <font color="#2166ae">`Array`</font>=>JSONArray
- <font color="#2166ae">`File`</font>=> Parse File
- <font color="#2166ae">`Pointer`</font>=> other ParseObject
- <font color="#2166ae">`Relation`</font>=> ParseRelation
- <font color="#2166ae">`Geopoint`</font>=> ParseGeoPoint

Each <font color="#2166ae">`ParseObject`</font> has a class name that we can use to distinguish different sorts of data. For example, we could call the high score object a <font color="#2166ae">`GameScore`</font>. There are also a few fields we don’t need to specify that are provided as a convenience:

- <font color="#2166ae">`objectId`</font>is a unique identifier for each saved object.
- <font color="#2166ae">`createdAt`</font>and <font color="#2166ae">`updatedAt`</font>represent the time that each object was created and last modified in the cloud.

Each of these fields is automatically filled in by Back4app at the moment we save a new <font color="#2166ae">`ParseObject`</font>.

:::hint{type="info"}
We recommend you <font color="#2166ae">`NameYourClassesLikeThis`</font> (UpperCamelCase) and <font color="#2166ae">`nameYourKeysLikeThis` </font>(lowerCamelCase), just to keep your code looking pretty.
:::

This tutorial uses a basic app created in Android Studio 4.1.1 with <font color="#2166ae">`buildToolsVersion=30.0.2`</font> , <font color="#2166ae">`Compile SDK Version`</font> = <font color="#2166ae">`30.0.2`</font> and <font color="#2166ae">`targetSdkVersion 30`</font>

:::hint{type="success"}
**At any time, you can access the complete Project via our GitHub repositories.**

- [Kotlin Example Repository](https://github.com/templates-back4app/android_crud_operations_kotlin)
- [Java Example Repository](https://github.com/templates-back4app/android_crud_operations_java)
:::

## Goal

Our goal is to create an Android App that can process all data types provided by Parse Server.
Here is a preview of what we are gonna achive:

::Image[]{src="https://api.archbee.com/api/optimize/yD3zCY-NNBBIfd0uqcfR5/v8KoOA0ezaDkvt7ZT1nFr_image.png" size="30" width="346" height="750" position="center" showCaption="false"}

## Prerequisites

:::hint{type="info"}
**To complete this tutorial, we need:**

- [Android Studio](https://developer.android.com/studio/index.html)
- An app created on Back4App.
  - **Note:&#x20;**&#x46;ollow the [New Parse App tutorial](https://www.back4app.com/docs/get-started/new-parse-app) to learn how to create a Parse App on Back4App.
- An android app connected to Back4App.
  - **Note:&#x20;**&#x46;ollow the [Install Parse SDK tutoria](https://www.back4app.com/docs/android/parse-android-sdk)l to create an Android Studio Project connected to Back4App.
- A device (or[ virtual device](https://developer.android.com/studio/run/managing-avds.html)) running Android 4.1 (Jelly Bean) or newer.
:::

## Understanding our App

You will create an app for a better understanding of Parse <font color="#2166ae">`Data Types`</font>. In this <font color="#2166ae">`Android`</font> app, you will create all data types in a class named <font color="#2166ae">`DataTypes`</font> and assign values to this classes variables. Then we will read and update this data.

:::hint{type="info"}
**Note** The data types <font color="#2166ae">`Pointer`</font>, <font color="#2166ae">`Relation`</font>, <font color="#2166ae">`File`</font>, <font color="#2166ae">`Geopoint`</font> will be covered later in specific guides.
:::

## Let’s get started!

## 1 - Create App Template

Define the following variables in the <font color="#2166ae">`MainActivity`</font> and replace the code in the <font color="#2166ae">`onCreate`</font> method with the following code.

:::CodeblockTabs
```java
1     private ProgressDialog progressDialog;
2     private View popupInputDialogView;
3     private RecyclerView recyclerView;
4     private String objectId;
5     private static final String TAG = "MainActivity";
6
7     @Override
8     protected void onCreate(Bundle savedInstanceState) {
9         super.onCreate(savedInstanceState);
10        setContentView(R.layout.activity_main);
11
12        progressDialog = new ProgressDialog(MainActivity.this);
13
14        Button saveData = findViewById(R.id.saveData);
15        Button readData = findViewById(R.id.readData);
16        Button updateData = findViewById(R.id.updateData);
17
18        saveData.setOnClickListener(saveDataView -> {
19            try {
20                saveDataTypes();
21            } catch (JSONException e) {
22                e.printStackTrace();
23            }
24        });
25
26        readData.setOnClickListener(readDataView -> readObjects());
27
28        updateData.setOnClickListener(updateDataView -> updateObject());
29
30    }
```

```kotlin
1     private var progressDialog: ProgressDialog? = null
2     private var objectId: String? = null
3     private var popupInputDialogView: View? = null
4     private var recyclerView: RecyclerView? = null
5     private val TAG = "MainActivity"
6
7     override fun onCreate(savedInstanceState: Bundle?) {
8        super.onCreate(savedInstanceState)
9         setContentView(R.layout.activity_main)
10
11        progressDialog = ProgressDialog(this@MainActivity)
12        val saveData = findViewById<Button>(R.id.saveData)
13        val readData = findViewById<Button>(R.id.readData)
14        val updateData = findViewById<Button>(R.id.updateData)
15        
16        saveData.setOnClickListener {
17            try {
18                saveDataTypes()
19            } catch (e: JSONException) {
20                e.printStackTrace()
21            }
22        }
23        readData.setOnClickListener { readObjects() }
24        updateData.setOnClickListener { updateObject() }
25    }
```
:::

:::hint{type="info"}
Before next steps, we need to connect <font color="#2166ae">`Back4App`</font> to our application. You should save the <font color="#2166ae">`appId`</font> and <font color="#2166ae">`clientKey`</font> from the <font color="#2166ae">`Back4App`</font> to <font color="#2166ae">`string.xml`</font> file and then init <font color="#2166ae">`Parse`</font> in our <font color="#2166ae">`App.java`</font> or <font color="#2166ae">`App.kt`</font> file.
Follow the [New Parse App tutorial](https://www.back4app.com/docs/android/parse-android-sdk) if you don’t know how to init <font color="#2166ae">`Parse`</font> to your app.
:::

## 2 - Code for Save Object

The create function will create a new object in Back4app database. We define the <font color="#2166ae">`saveDataTypes`</font> function that we call in the <font color="#2166ae">`onCreate`</font> function and use the following code in this function. We will save all data types with this function to the DataTypes classes object.

:::CodeblockTabs
```java
1  private void saveDataTypes() throws JSONException{
2      ParseObject parseObject = new ParseObject("DataTypes");
3
4         parseObject.put("stringField", "String");
5         parseObject.put("doubleField", 1.5);
6         parseObject.put("intField", 2);
7         parseObject.put("boolField", true);
8         parseObject.put("dateField", Calendar.getInstance().getTime());
9
10        JSONObject myObject = new JSONObject();
11        myObject.put("number", 1);
12        myObject.put("string", "42");
13
14        parseObject.put("jsonObject", myObject);
15
16
17        JSONArray myArray = new JSONArray();
18        myArray.put(myObject);
19        myArray.put(myObject);
20        myArray.put(myObject);
21
22        parseObject.put("jsonArray", myArray);
23
24
25        List<String> list = new ArrayList<>();
26        list.add("string1");
27        list.add("string2");
28        parseObject.put("listStringField", list);
29
30        List<Integer> listInt = new ArrayList<>();
31        listInt.add(1);
32        listInt.add(2);
33        listInt.add(3);
34        parseObject.put("listIntField", listInt);
35
36        List<Boolean> listBool = new ArrayList<>();
37        listBool.add(true);
38        listBool.add(false);
39        parseObject.put("listBoolField", listBool);
40
41        progressDialog.show();
42        parseObject.saveInBackground(e -> {
43            progressDialog.dismiss();
44            if (e == null) {
45                Toast.makeText(this, "Object created successfully...", Toast.LENGTH_SHORT).show();
46                objectId = parseObject.getObjectId();
47            } else {
48                objectId = null;
49                Toast.makeText(this, e.getMessage(), Toast.LENGTH_LONG).show();
50            }
51        });
52    }
```

```kotlin
1     private fun saveDataTypes() {
2     val parseObject = ParseObject("DataTypes")
3
4         parseObject.put("stringField", "String")
5         parseObject.put("doubleField", 1.5)
6         parseObject.put("intField", 2)
7         parseObject.put("boolField", true)
8         parseObject.put("dateField", Calendar.getInstance().time)
9
10
11        val myObject = JSONObject()
12        myObject.put("number", 1)
13        myObject.put("string", "42")
14
15        parseObject.put("jsonObject", myObject)
16
17        val myArray = JSONArray()
18        myArray.put(myObject)
19        myArray.put(myObject)
20        myArray.put(myObject)
21
22        parseObject.put("jsonArray", myArray)
23
24        val list: MutableList<String> = ArrayList()
25        list.add("string1")
26        list.add("string2")
27        parseObject.put("listStringField", list)
28
29        val listInt: MutableList<Int> = ArrayList()
30        listInt.add(1)
31        listInt.add(2)
32        listInt.add(3)
33        parseObject.put("listIntField", listInt)
34
35        val listBool: MutableList<Boolean> = ArrayList()
36        listBool.add(true)
37        listBool.add(false)
38        parseObject.put("listBoolField", listBool)
39
40        progressDialog?.show()
41        parseObject.saveInBackground {
42            progressDialog?.dismiss()
43            if (it == null) {
44                Toast.makeText(this, "Object created successfully...", Toast.LENGTH_SHORT).show()
45                objectId = parseObject.objectId
46            } else {
47                objectId = null
48                Toast.makeText(this, it.message, Toast.LENGTH_LONG).show()
49            }
50        }
51   }
```
:::

## 3 - Code for Read Object

We will give the <font color="#2166ae">`objectId`</font> variable that we have assigned in the <font color="#2166ae">`saveDataTypes`</font> function as a parameter to the query and read the data that we have saved in the <font color="#2166ae">`saveDataTypes`</font> function with the <font color="#2166ae">`readObjects`</font> function.

:::CodeblockTabs
```java
1 private void readObjects() {
2    if (objectId == null) {
3             Toast.makeText(this, "No object. Click on the 'Save Data' button before.", Toast.LENGTH_SHORT).show();
4             return;
5         }
6
7         ParseQuery<ParseObject> query = new ParseQuery<>("DataTypes");
8
9         progressDialog.show();
10        query.getInBackground(objectId, (object, e) -> {
11            progressDialog.dismiss();
12            if (e == null) {
13                List<Data> list = new ArrayList<>();
14                list.add(new Data("Int list field",object.get("listIntField").toString()));
15                list.add(new Data("String field",object.get("stringField").toString()));
16                list.add(new Data("Double field",object.get("doubleField").toString()));
17                list.add(new Data("Int field",object.get("intField").toString()));
18                list.add(new Data("String list field",object.get("listStringField").toString()));
19                list.add(new Data("Date field",object.get("dateField").toString()));
20                list.add(new Data("Bool field",object.get("boolField").toString()));
21                list.add(new Data("List Bool field",object.get("listBoolField").toString()));
22                list.add(new Data("Json Object field",object.get("jsonObject").toString()));
23                list.add(new Data("Json Array field",object.get("jsonArray").toString()));
24
25                showDataTypes(list);
26
27            } else {
28                Toast.makeText(this, e.getMessage(), Toast.LENGTH_SHORT).show();
29            }
30        });
31 }
```

```kotlin
1 private fun readObjects() {
2    if (objectId == null) {
3             Toast.makeText(
4                 this,
5                 "No object. Click on the 'Save Data' button before.",
6                 Toast.LENGTH_SHORT
7             ).show()
8             return
9         }
10
11        val query = ParseQuery<ParseObject>("DataTypes")
12
13
14        progressDialog?.show()
15        query.getInBackground(
16            objectId
17        ) { obj, e ->
18            progressDialog?.dismiss()
19            if (e == null) {
20
21                val list: MutableList<Data> = ArrayList()
22                list.add(Data("Int list field", obj.get("listIntField").toString()))
23                list.add(Data("String field",obj.get("stringField").toString()))
24                list.add(Data("Double field", obj.get("doubleField").toString()))
25                list.add(Data("Int field", obj.get("intField").toString()))
26                list.add(Data("String list field", obj.get("listStringField").toString()))
27                list.add(Data("Date field",obj.get("dateField").toString()))
28                list.add(Data("Bool field", obj.get("boolField").toString()))
29                list.add(Data("List Bool field", obj.get("listBoolField").toString()))
30                list.add(Data("Json Object field", obj.get("jsonObject").toString()))
31                list.add(Data("Json Array field", obj.get("jsonArray").toString()))
32                showDataTypes(list)
33            } else {
34                Toast.makeText(this, e.message, Toast.LENGTH_SHORT).show()
35            }
36
37        }
38 }
```
:::

In this section, we have created a model class called <font color="#2166ae">`Data`</font>. We use the data we get in the <font color="#2166ae">`readObjects`</font> function to create objects from this model class. We give these objects as elements to the list we created in <font color="#2166ae">`Data`</font> type. Then we give this list as a parameter to the <font color="#2166ae">`showDataTypes`</font> function and list it in the <font color="#2166ae">`AlertDialog`</font>.

This is the <font color="#2166ae">`Data`</font> model.&#x20;

:::CodeblockTabs
```java
1   public class Data {
2    private String type;
3    private String value;
4
5    public Data(String type, String value) {
6        this.type = type;
7        this.value = value;
8    }
9
10    public String getType() {
11        return type;
12    }
13
14    public Data setType(String type) {
15        this.type = type;
16        return this;
17    }
18
19    public String getValue() {
20        return value;
21    }
22
23    public Data setValue(String value) {
24        this.value = value;
25        return this;
26    }
27   }
```

```kotlin
1   class Data(val type:String?=null,val value:String?=null) {
2
3   }
```
:::

This is the <font color="#2166ae">`showDataTypes`</font> function.

:::CodeblockTabs
```java
1   private void showDataTypes(List<Data> list){
2        AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(MainActivity.this);
3        alertDialogBuilder.setTitle("Data types");
4        alertDialogBuilder.setCancelable(true);
5        initPopupViewControls(list);
6        //We are setting our custom popup view by AlertDialog.Builder
7        alertDialogBuilder.setView(popupInputDialogView);
8        final AlertDialog alertDialog = alertDialogBuilder.create();
9        alertDialog.show();
10    }
11
12    private void initPopupViewControls(List<Data> list) {
13        LayoutInflater layoutInflater = LayoutInflater.from(MainActivity.this);
14        popupInputDialogView = layoutInflater.inflate(R.layout.custom_alert_dialog, null);
15        recyclerView = popupInputDialogView.findViewById(R.id.recyclerView);
16        ItemAdapter adapter = new ItemAdapter(list,this);
17        recyclerView.setLayoutManager(new LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false));
18        recyclerView.setAdapter(adapter);
19    }
```

```kotlin
1    private fun showDataTypes(list: List<Data>) {
2         val alertDialogBuilder = AlertDialog.Builder(this@MainActivity)
3         alertDialogBuilder.setTitle("Data types")
4         alertDialogBuilder.setCancelable(true)
5         initPopupViewControls(list)
6         //We are setting our custom popup view by AlertDialog.Builder
7         alertDialogBuilder.setView(popupInputDialogView)
8         val alertDialog = alertDialogBuilder.create()
9         alertDialog.show()
10    }
11
12    @SuppressLint("InflateParams")
13    private fun initPopupViewControls(list: List<Data>) {
14        val layoutInflater = LayoutInflater.from(this@MainActivity)
15        popupInputDialogView = layoutInflater.inflate(R.layout.custom_alert_dialog, null)
16        recyclerView = popupInputDialogView?.findViewById(R.id.recyclerView)
17        val adapter = ItemAdapter(this@MainActivity, list)
18        recyclerView?.layoutManager = LinearLayoutManager(
19            this,
20            LinearLayoutManager.VERTICAL,
21            false
22        )
23        recyclerView?.adapter = adapter
24    }
```
:::

## 4 - Code for Update Object

The <font color="#2166ae">`updateObject`</font> function is responsible for updating data in the object created on the <font color="#2166ae">`saveDataTypes`</font> function. We are using <font color="#2166ae">`objectId`</font> again for update object.

:::CodeblockTabs
```java
1   public void updateObject() {
2      if (objectId == null) {
3           Toast.makeText(this, "No object. Click on the 'Save Data' button before.", Toast.LENGTH_SHORT).show();
4           return;
5       }
6
7       ParseObject parseObject = new ParseObject("DataTypes");
8       parseObject.setObjectId(objectId);
9       parseObject.put("intField", 5);
10      parseObject.put("stringField", "new String");
11
12      progressDialog.show();
13
14      parseObject.saveInBackground(e -> {
15          progressDialog.dismiss();
16          if (e == null) {
17              Toast.makeText(this, "Object updated successfully...", Toast.LENGTH_SHORT).show();
18          } else {
19              Toast.makeText(this, e.getMessage(), Toast.LENGTH_SHORT).show();
20          }
21      });
22  }
```

```kotlin
1   private fun updateObject() {
2      if (objectId == null) {
3           Toast.makeText(
4               this,
5               "No object. Click on the 'Save Data' button before.",
6               Toast.LENGTH_SHORT
7           ).show()
8           return
9       }
10
11      val parseObject = ParseObject("DataTypes")
12      parseObject.objectId = objectId
13      parseObject.put("intField", 5)
14      parseObject.put("stringField", "new String")
15
16      progressDialog?.show()
17
18      parseObject.saveInBackground {
19          progressDialog?.dismiss()
20          if (it == null) {
21              Toast.makeText(this, "Object updated successfully...", Toast.LENGTH_SHORT).show()
22          } else {
23              Toast.makeText(this, it.message, Toast.LENGTH_SHORT).show()
24          }
25      }
26  }
```
:::

## 5 - Using Counters

The above example contains a common use case. The <font color="#2166ae">`intField`</font> field can be a counter that we’ll need to update continually. The above solution works, but it’s cumbersome and can lead to problems if we have multiple clients trying to update the same counter. Parse provides methods that atomically increment any number field to help with storing counter-type data. So, the same update can be rewritten as:

:::CodeblockTabs
```java
1    ParseObject parseObject = new ParseObject("DataTypes");
2    parseObject.setObjectId(objectId);
3    parseObject.increment("intField",1);
```

```kotlin
1    val parseObject = ParseObject("DataTypes")
2    parseObject.objectId = objectId
3    parseObject.increment("intField",1)
```
:::

## 6 - Using Lists

Parse also provides methods to help in storing list data. There are three operations that can be used to change a list field atomically:

- <font color="#2166ae">`setAdd`</font>and <font color="#2166ae">`setAddAll`</font>: append the given objects to the end of an array field.
- <font color="#2166ae">`setAddUnique`</font>and <font color="#2166ae">`setAddAllUnique`</font>\:add only the given objects which aren’t already contained in an array field to that field. The position of the insert is not guaranteed.
- <font color="#2166ae">`remove`</font>and <font color="#2166ae">`removeAll`</font>: removes all instances of the given objects from an array field.

### 6.1 - Examples with add and addAll

<font color="#2166ae">`listStringField`</font> has the value:

:::BlockQuote
\["a","b","c","d","e","f","g","g"]
:::

Running the code below:

:::CodeblockTabs
```java
1        ParseObject parseObject = new ParseObject("DataTypes");
2        parseObject.setObjectId(objectId);
3        parseObject.add("listStringField","e");
4        parseObject.addAll("listStringField", Arrays.asList("e", "f", "g", "g"));
5        parseObject.save();
```

```kotlin
1        val parseObject = ParseObject("DataTypes")
2        parseObject.objectId = objectId
3        parseObject.add("listStringField", "e")
4        parseObject.addAll("listStringField", Arrays.asList("e", "f", "g", "g"))
5        parseObject.save()
```
:::

After this command the result of the stringList field will be:

:::BlockQuote
\["a","b","c","d","e","e","f","g","g"]
:::

### 6.2 - Examples with addUnique and addAllUnique

<font color="#2166ae">`listStringField`</font> has the value:

:::BlockQuote
\["a","b","c","d","e"]
:::

Running the code below:

:::CodeblockTabs
```java
1        ParseObject parseObject = new ParseObject("DataTypes");
2        parseObject.setObjectId(objectId);
3        parseObject.addUnique("listStringField","e");
4        parseObject.addAllUnique("listStringField",Arrays.asList("c", "d", "e", "f"));
5        parseObject.save();
```

```kotlin
1        val parseObject = ParseObject("DataTypes")
2        parseObject.objectId = objectId
3        parseObject.addUnique("listStringField", "e")
4        parseObject.addAllUnique("listStringField", Arrays.asList("c", "d", "e", "f"))
5        parseObject.save()
```
:::

After this command the result of the<font color="#2166ae">`stringList`</font> field will be:

:::BlockQuote
\["a","b","c","d","e","f"]
:::

No values were repeated.

### 6.3 - Examples with removeAll

<font color="#2166ae">`listStringField`</font> has the value:

:::BlockQuote
\["a","b","c","d","e","f"]
:::

Running the code below:

:::CodeblockTabs
```java
1        ParseObject parseObject = new ParseObject("DataTypes");
2        parseObject.setObjectId(objectId);
3        parseObject.removeAll("listStringField",Arrays.asList("c", "d", "e", "f"));
4        parseObject.save();
```

```kotlin
1        val parseObject = ParseObject("DataTypes")
2        parseObject.objectId = objectId
3        parseObject.removeAll("listStringField", Arrays.asList("c", "d", "e", "f"))
4        parseObject.save()
```
:::

After this command the result of the<font color="#2166ae">`stringList`</font> field will be:

:::BlockQuote
\["a","b"]
:::

:::hint{type="info"}
**Note** that it is not currently possible to atomically add and remove items from an array in the same save. We will have to call the save for every different array operation we want to perform separately.
:::

## 7 - Remove single field from ParseObject

You can delete a single field from an object by using the <font color="#2166ae">`remove`</font> operation:

:::CodeblockTabs
```java
1    ParseObject parseObject = new ParseObject("DataTypes");
2    parseObject.remove("stringField");
3    parseObject.save();
```

```kotlin
1       val parseObject = ParseObject("DataTypes")
2       parseObject.remove("stringField")
3       parseObject.save()
```
:::

## It’s done!

At this point, we have learned <font color="#2166ae">`Parse Data Types`</font> on <font color="#2166ae">`Android`</font>.