Android GridView - CRUD - ADD UPDATE DELETE

android crud

Android GridView CRUD tutorial.

Hello.We see how to perform basic CRUD operations against GridView.

  • We add,update and delete.
  • Our basic data source is an arraylist.
  • Our adapter is ArrayAdapter.

Let's start.

1. Build.Gradle**

  • Add dependencies for AppCompat and Design support libraries.
  • Our MainActivity shall derive from AppCompatActivity while we shall also use Floating action button from design support libraries.

 

apply plugin: 'com.android.application'

android {
    compileSdkVersion 24
    buildToolsVersion "24.0.1"

    defaultConfig {
        applicationId "com.tutorials.hp.gridview_crud"
        minSdkVersion 15
        targetSdkVersion 24
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:24.1.1'
    compile 'com.android.support:design:24.1.1'
}

 

2. CRUD.java**

  • Perform basic CRUD operations like adding,updating and deleting.
package com.tutorials.hp.gridview_crud;

import java.util.ArrayList;

public class CRUD {

    private ArrayList<String> names =new ArrayList<>();

    public void save(String name)
    {
       names.add(name);
    }

    public ArrayList<String> getNames()
    {

        return names;
    }

    public Boolean update(int position,String newName)
    {
       try {
           names.remove(position);
           names.add(position,newName);

           return true;
       }catch (Exception e)
       {
           e.printStackTrace();
          return false;
        }
    }

    public Boolean delete(int position)
    {
        try {
            names.remove(position);

            return true;
        }catch (Exception e)
        {
            e.printStackTrace();
            return false;

        }
    }
}

3. MainActivity.java**

  • Launcher activity.
  • ActivityMain.xml inflated as the contentview for this activity.
  • Reference our GridView.
package com.tutorials.hp.gridview_crud;

import android.app.Dialog;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.GridView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    GridView gv;
    ArrayAdapter<String> adapter;
    CRUD crud=new CRUD();
    Dialog d;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        gv= (GridView) findViewById(R.id.gv);

        gv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                if(d != null) {
                    if(!d.isShowing())
                    {
                        displayInputDialog(i);
                    }else
                    {
                        d.dismiss();
                    }
                }
            }
        });

        final FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
             //DISPLAY DIALOG FOR NEW DATA
                displayInputDialog(-1);
            }
        });
    }
    private void displayInputDialog(final int pos)
    {
        d=new Dialog(this);
        d.setTitle("GRIDVIEW CRUD");
        d.setContentView(R.layout.input_dialog);

        final EditText nameEditTxt= (EditText) d.findViewById(R.id.nameEditText);
        Button addBtn= (Button) d.findViewById(R.id.addBtn);
        Button updateBtn= (Button) d.findViewById(R.id.updateBtn);
        Button deleteBtn= (Button) d.findViewById(R.id.deleteBtn);

        if(pos== -1)
        {
            addBtn.setEnabled(true);
            updateBtn.setEnabled(false);
            deleteBtn.setEnabled(false);
        }else
        {
            addBtn.setEnabled(true);
            updateBtn.setEnabled(true);
            deleteBtn.setEnabled(true);
            nameEditTxt.setText(crud.getNames().get(pos));
        }

        addBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //GET DATA
                String name=nameEditTxt.getText().toString();

                //VALIDATE
                if(name.length()>0 && name != null)
                {
                    //save
                    crud.save(name);
                    nameEditTxt.setText("");
                    adapter=new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,crud.getNames());
                    gv.setAdapter(adapter);

                }else
                {
                    Toast.makeText(MainActivity.this, "Name cannot be empty", Toast.LENGTH_SHORT).show();
                }
            }
        });
        updateBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //GET DATA
                String newName=nameEditTxt.getText().toString();

                //VALIDATE
                if(newName.length()>0 && newName != null)
                {
                    //save
                    if(crud.update(pos,newName))
                    {
                        nameEditTxt.setText(newName);
                        adapter=new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,crud.getNames());
                        gv.setAdapter(adapter);
                    }

                }else
                {
                    Toast.makeText(MainActivity.this, "Name cannot be empty", Toast.LENGTH_SHORT).show();
                }
            }
        });
        deleteBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                //DELETE
                if( crud.delete(pos))
                {
                    nameEditTxt.setText("");
                    adapter=new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,crud.getNames());
                    gv.setAdapter(adapter);
                }
            }
        });

        d.show();
    }
}

4. ActivityMain.xml**

  • To contain our ContentMain.xml.
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context="com.tutorials.hp.gridview_crud.MainActivity">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay" />

    </android.support.design.widget.AppBarLayout>

    <include layout="@layout/content_main" />

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|end"
        android:layout_margin="@dimen/fab_margin"
        android:src="@android:drawable/ic_dialog_email" />

</android.support.design.widget.CoordinatorLayout>

 

5. ContentMain.xml**

  • To hold our adapterview.

 

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.tutorials.hp.gridview_crud.MainActivity"
    tools:showIn="@layout/activity_main">

    <GridView
        android:id="@+id/gv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:numColumns="3" />
</RelativeLayout>

 

6. InputDialog.xml**

  • handles inputs

 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="match_parent"
        android:layout_marginTop="?attr/actionBarSize"
        android:orientation="vertical"
        android:paddingLeft="15dp"
        android:paddingRight="15dp"
        android:paddingTop="10dp">

        <android.support.design.widget.TextInputLayout
            android:id="@+id/nameLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <EditText
                android:id="@+id/nameEditText"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:singleLine="true"
                android:hint= "Name" />
        </android.support.design.widget.TextInputLayout>

<LinearLayout
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
    <Button android:id="@+id/addBtn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="ADD"
        android:clickable="true"
        android:background="@color/colorAccent"
        android:layout_marginTop="20dp"
        android:textColor="@android:color/white"/>

    <Button android:id="@+id/updateBtn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="UPDATE"
        android:clickable="true"
        android:background="#009968"
        android:layout_marginTop="20dp"
        android:textColor="@android:color/white"/>

    <Button android:id="@+id/deleteBtn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="DELETE"
        android:clickable="true"
        android:background="#2fc1b9"
        android:layout_marginTop="20dp"
        android:textColor="@android:color/white"/>
</LinearLayout>
         </LinearLayout>

</LinearLayout>

How To Run

  1. Download the project.
  2. You'll get a zipped file,extract it.
  3. Open the Android Studio.
  4. Now close, already open project.
  5. From the Menu bar click on File >New> Import Project.
  6. Now Choose a Destination Folder, from where you want to import project.
  7. Choose an Android Project.
  8. Now Click on “OK“.
  9. Done, your done importing the project,now edit it.

More Resources

Resource Link
GitHub Browse Browse
GitHub Download Link Download

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