Android : Android Calendar Skeleton

I'm trying to create a Calendar app for Android using Android Studio and I was wondering if I could get some code hints regarding how to set up a grid that will have 7 columns and 5 rows

For the rows, I'd like to have like 3-4 dates on the first row and last one, whereas for the rest 7 elements.

Cheers!

What I got so far:

My main activity:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    tools:context=".MyActivity"
    android:weightSum="1">

    <LinearLayout
        android:id="@+id/buttonlayout"
        android:layout_width="220dp"
        android:layout_height="60sp"
        android:background="@drawable/topbar"
        android:orientation="horizontal"
        android:layout_gravity="center_horizontal">

        <ImageView
            android:id="@+id/prevMonth"
            android:layout_width="20sp"
            android:layout_height="fill_parent"
            android:layout_gravity="center"
            android:src="@drawable/calendar_left_arrow_selector"/>

        <TextView
            android:id="@+id/currentMonth"
            android:layout_width="180sp"
            android:layout_height="fill_parent"
            android:gravity="center"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:textColor="@color/fontColorUnselected"/>

        <ImageView
            android:id="@+id/nextMonth"
            android:layout_width="20sp"
            android:layout_height="fill_parent"
            android:src="@drawable/calendar_right_arrow_selector"
            android:layout_gravity="center"/>
    </LinearLayout>

    <GridView
        android:id="@+id/calendar"
        android:layout_width="fill_parent"
        android:layout_height="280dp"
        android:layout_marginTop="20sp"
        android:numColumns="7">
    </GridView>

    <ImageView
        android:layout_width="127dp"
        android:layout_height="100dp"
        android:src="@drawable/calendar"
        android:layout_gravity="center"
        android:layout_weight="0.50"
        android:layout_marginTop="15dp">

    </ImageView>

    </LinearLayout>


screen_gridcell.xml

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:background="@color/dataFieldUnselected">

    <Button
        android:id="@+id/calendar_day_gridcell"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:textColor="@color/fontColorUnselected"
        android:background="@drawable/calendar_button_selector"
        android:textSize="20dp"
        />

</RelativeLayout>

Using this, it fills up all the gap spaces, therefore I get 7 elements on each row. I would also like not to use pictures for the dates since it will load the application a bit, and try customizing things such as borders from the main activity