How to set the background colour of individual gridview cells

The key to solving this problem is to first understand how ListView and GridView work. GridView creates and destroys child views as you scroll up and down. If you can't see an item in a GridView that means there is no child view for it, it will be created when the user actually scrolls to it. GridView uses an Adapter to create the views and GridView recycles views when they go offscreen and asks the Adapter to reuse the recycled views for new views that come on screen. The Adapter usually inflates a resource layout to create new views.

So what this means is that GridView will call getView(...) on the Adapter each time it wants to display a child view on screen, it may pass a recycled View called convertView.

The solution is to override getView(...), call super to let the Adapter create and populate the view with data from the String array normally but add a bit of code at the end before we give the view back to GridView that sets the color of the view.

new ArrayAdapter<String>(context, android.R.layout.simple_list_item_1, student_array) { @Override public View getView(int position, View convertView, ViewGroup parent) { View view = super.getView(position, convertView, parent); int color = 0x00FFFFFF; // Transparent if (someCondition) { color = 0xFF0000FF; // Opaque Blue } view.setBackgroundColor(color); return view; } }; 

Main activity where you have to create array of hexadecimal color code and and pass to custom adapter class

public class MainActivity extends Activity { GridView gridView; String[] gridColor ={ "#008B8B", "#00FF00", "#48D1CC", "#556B2F", "#696969", "#6B8E23", "#8FBC8F", "#AFEEEE", "#B8860B", "#BDB76B", "#D8BFD8", "#DEB887", "#FFFF00", "#FFF0F5", "#EE82EE", "#DC143C", "#C0C0C0" }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Grid adapter = new Grid(MainActivity.this,gridColor); gridView=(GridView)findViewById(R.id.grid_view); gridView.setAdapter(adapter); gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { Toast.makeText(MainActivity.this, "You Clicked On " +gridcolor[+ position], Toast.LENGTH_SHORT).show(); } }); } } 

Custom adapter code should be like this where color codes are parsed.

public class Grid extends BaseAdapter { private Context mContext; private final String[] menu; private final int[] Imageid; private final String[] gridcolor; public Grid(Context context,String[] menu,int[] Imageid,String[] gridcolor) { mContext=context; this.gridcolor=gridcolor; } @Override public int getCount() { return gridcolor.length; } @Override public Object getItem(int i) { return null; } @Override public long getItemId(int i) { return 0; } @Override public View getView(int i, View view, ViewGroup viewGroup) { View grid; LayoutInflater inflater = (LayoutInflater) mContext .getSystemService(Context.LAYOUT_INFLATER_SERVICE); if (view == null) { grid = new View(mContext); grid = inflater.inflate(R.layout.grid_layout, null); grid.setBackgroundColor(Color.parseColor(gridcolor[i])); } else { grid = view; } return grid; } } 

You need to create a custom layout and use it in your adapter instead of android.R.layout.simple_list_item_1. For example:

<TextView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@android:id/text1" android:layout_width="match_parent" android:layout_height="wrap_content" android:textAppearance="?android:attr/textAppearanceListItemSmall" android:gravity="center_vertical" android:paddingLeft="?android:attr/listPreferredItemPaddingLeft" android:paddingRight="?android:attr/listPreferredItemPaddingRight" android:minHeight="?android:attr/listPreferredItemHeightSmall" android:background="#18A608" /> 

(I simply copied the latest version of simple_list_item_1.xml and added the new background color at the end.)

Save this as grid_layout.xml in res/layout and change your adapter's constructor to:

ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.grid_layout, student_array);