sql database android studio sqlite example

Searching a SQLite Database in Android Studio - Example

In this practical, you should be familiar with the basics of Android development and have a good understanding of how to use Android Studio. This course is now deprecated, but a new version is available at 'Android Developer Fundamentals course (Version 2)' or go directly to Lesson 11: Sharing Data with Content Providers.

If you're just starting out, it's recommended that you complete the following lessons before proceeding:

1.1A: Implementing a Minimalist Content Provider

1.1B: Adding a Content Provider to Your Database

2.1: Loading and Displaying Fetched Data

Once you have a basic understanding of content providers, you can move on to this practical. In this lesson, we'll learn how to search a SQLite database in Android Studio.

Firstly, let's create a new project in Android Studio. Go to File > New > New Project and follow the prompts to create a new Android application. Name your project 'SQLite Search' for example.

Next, open the res/layout/activity_main.xml file and add the following code:

```xml

xmlns:app='http://schemas.android.com/apk/res-auto'

android:layout_width='match_parent'

android:layout_height='match_parent'

android:orientation='vertical'>

android:id='@+id/search_edit_text'

android:layout_width='match_parent'

android:layout_height='wrap_content'

android:hint='Search for a name' />

android:id='@+id/search_results_list_view'

android:layout_width='match_parent'

android:layout_height='wrap_content' />

```

This will create an activity with an edit text field and a list view where we'll display the search results.

Next, open the res/values/strings.xml file and add the following code:

```xml

SQLite Search

Search for a name

```

This will create some default strings for our app.

Now, let's move on to the Java code. Open the MainActivity.java file and add the following code:

```java

import android.app.Activity;

import android.content.ContentResolver;

import android.database.Cursor;

import android.os.Bundle;

import android.provider.ContactsContract;

import android.view.View;

import android.widget.EditText;

import android.widget.ListView;

import java.util.ArrayList;

import java.util.List;

public class MainActivity extends Activity {

private EditText searchEditText;

private ListView searchResultsListView;

private List searchResults = new ArrayList<>();

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

searchEditText = (EditText) findViewById(R.id.search_edit_text);

searchResultsListView = (ListView) findViewById(R.id.search_results_list_view);

searchEditText.addTextChangedListener(new TextWatcher() {

@Override

public void beforeTextChanged(CharSequence s, int start, int count, int after) {

}

@Override

public void onTextChanged(CharSequence s, int start, int before, int count) {

}

@Override

public void afterTextChanged(Editable s) {

searchEditText(s.toString());

}

});

}

private void searchEditText(String query) {

ContentResolver contentResolver = getContentResolver();

Cursor cursor = contentResolver.query(ContactsContract.Contacts.CONTENT_URI, null, null, null, null);

if (cursor != null && cursor.moveToFirst()) {

do {

String name = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));

if (name.toLowerCase().contains(query.toLowerCase())) {

searchResults.add(name);

}

} while (cursor.moveToNext());

cursor.close();

}

searchResultsListView.setAdapter(new ArrayAdapter(this, android.R.layout.simple_list_item_1, searchResults));

}

```

This code will create an activity with a search edit text field and a list view where we'll display the search results. When the user enters a query in the edit text field and presses enter, it will search for contacts in the SQLite database that match the query and display them in the list view.

Finally, run your app on an emulator or physical device to test it out. You can use the following steps to test:

1. Open the app on your device.

2. Type a name in the edit text field and press enter.

3. The app should search for contacts that match the query and display them in the list view.

That's it! This is a basic example of how to search a SQLite database in Android Studio using an EditText field and a ListView.