how to Set text, text color, image in Android using Java

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="vertical"
  android:background="#004444" >
<TextView
  android:id="@+id/textView1"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:textSize="30sp"
  android:textColor="#000"
  android:text="saturday"
/>
<ImageView
  android:id="@+id/imageView1"
  android:layout_width="200dp"
  android:layout_height="200dp"
/>
</LinearLayout>

//put any image to res/drawable folder

MainActivity.java

import android.os.Bundle;
import android.widget.ImageView;
import android.widget.TextView; 
import android.app.Activity;
import android.graphics.Color;

public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  //set layout
  setContentView(R.layout.activity_main);
  //initialize text view object
  TextView tv=(TextView)findViewById(R.id.textView1);
  //set text color
  tv.setTextColor(Color.RED);
  //set text
  tv.setText("This is my first app");
  //initialize image view object
  ImageView im=(ImageView)findViewById(R.id.imageView1);
  //set image resource
  im.setImageResource(R.drawable.myimage);
  }
}