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How to Add and Remove Grids in GridView Dynamically


In this post, I will show you how to add and remove grids in GridView. And also, I am explained about SharedPreferences.
Project Structure:
Create a new Project in Eclipse/Android Studio with the required Specifications.
Codes:
activity_main.xml
Create activity_main.xml and replace it with the following code
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:weightSum="5"
android:orientation="vertical">

<GridView
android:id="@+id/gridView1"
android:layout_width="match_parent"
android:layout_height="0dp"
android:columnWidth="100dp"
android:gravity="center"
android:numColumns="auto_fit"
android:stretchMode="columnWidth"
android:layout_weight="4.5"/>

<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="0.5"
android:orientation="horizontal"
android:weightSum="2" >

<Button
android:id="@+id/btn_add"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:background="@null"
android:text="@string/hint_add"/>

<Button
android:id="@+id/btn_remove"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:background="@null"
android:text="@string/hint_remove"/>

</LinearLayout>

</LinearLayout>

activity_main_single.xml
Create activity_main_single.xml and replace it with the following code
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="5dp"
android:orientation="vertical"
android:gravity="center">

<ImageView
android:id="@+id/grid_item_image"
android:layout_width="50dp"
android:layout_height="50dp"
android:src="@mipmap/ic_launcher"
android:contentDescription="@string/app_name"
android:gravity="center" />

<TextView
android:id="@+id/grid_item_label"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/label"
android:textSize="15sp"
android:gravity="center" />

</LinearLayout>

MainActivity.java
Open MainActivity.java and replace it with the following code
package com.example.grid;

import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.GridView;
import android.widget.Toast;

import com.example.grid.adapter.ImageAdapter;

import java.util.ArrayList;

public class MainActivity extends Activity {

GridView gridView;
Button btn_add, btn_remove;
ImageAdapter adapter;
ArrayList<String> list;
SharedPreferences sharedPreferences;
SharedPreferences.Editor editor;
String Pref_Name = "Grid";
int count = 3;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

gridView = (GridView) findViewById(R.id.gridView1);
btn_add = (Button) findViewById(R.id.btn_add);
btn_remove = (Button) findViewById(R.id.btn_remove);

sharedPreferences = getSharedPreferences(Pref_Name, MODE_PRIVATE);
count = sharedPreferences.getInt("count", 3);

list = new ArrayList<>();

for (int i = 0; i < count; i++) {
list.add("");
}

adapter = new ImageAdapter(this, list);
gridView.setAdapter(adapter);

btn_add.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
list.add("");
adapter.notifyDataSetChanged();
gridView.setAdapter(adapter);

editor = sharedPreferences.edit();
editor.putInt("count", count + 1);
editor.apply();

Toast.makeText(getApplicationContext(), "One Image Added", Toast.LENGTH_SHORT).show();

}
});

btn_remove.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
list.remove("");
adapter.notifyDataSetChanged();
gridView.setAdapter(adapter);

editor = sharedPreferences.edit();
editor.putInt("count", count - 1);
editor.apply();

Toast.makeText(getApplicationContext(), "One Image Removed", Toast.LENGTH_SHORT).show();
}
});
}
}
ImageAdapter.java
Open ImageAdapter.java and replace it with the following code
package com.example.grid.adapter;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.grid.R;

import java.util.ArrayList;

public class ImageAdapter extends BaseAdapter {

private Context context;
private ArrayList list = new ArrayList<>();

public ImageAdapter(Context context, ArrayList list) {
this.context = context;
this.list = list;
}

@Override
public int getCount() {
return list.size();
}

@Override
public Object getItem(int position) {
return null;
}

@Override
public long getItemId(int position) {
return 0;
}

public View getView(int position, View convertView, ViewGroup parent) {

LayoutInflater inflater = (LayoutInflater) Context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.activity_main_single, null);
TextView textView = (TextView) convertView.findViewById(R.id.grid_item_label);
ImageView imageView = (ImageView) convertView.findViewById(R.id.grid_item_image);

int option = ((position+1)%3);

switch (option) {
case 0:
textView.setText("Windows");
imageView.setImageResource(R.drawable.windows_logo);
break;
case 1:
textView.setText("Android");
imageView.setImageResource(R.drawable.android_logo);
break;
case 2:
textView.setText("IOS");
imageView.setImageResource(R.drawable.ios_logo);
break;
default:
textView.setText("Android");
imageView.setImageResource(R.drawable.android_logo);
break;
}

return convertView;

}

}

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