Aim:
To develop a Simple Android Application that draws basic Graphical Primitives on the screen.
Procedure:
Creating a New project:
- Open Android Studio and then click on File -> New -> New project.
- Then type the Application name as “ex.no.4″ and click Next.
- Then select the Minimum SDK as shown below and click Next.
- Then select the Empty Activity and click Next.
- Finally click Finish.
- It will take some time to build and load the project.
- After completion it will look as given below.
Designing layout for the Android Application:
- Click on app -> res -> layout -> activity_main.xml.
- Now click on Text as shown below.
- Then delete the code which is there and type the code as given below.
Code for Activity_main.xml:
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <ImageView android:layout_width="match_parent" android:layout_height="match_parent" android:id="@+id/imageView" /> </RelativeLayout>
- Now click on Design and your application will look as given below.
- So now the designing part is completed.
Java Coding for the Android Application:
- Click on app -> java -> com.example.exno4 -> MainActivity.
- Then delete the code which is there and type the code as given below.
Code for MainActivity.java:
package com.example.exno4; import android.app.Activity; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.drawable.BitmapDrawable; import android.os.Bundle; import android.widget.ImageView; public class MainActivity extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //Creating a Bitmap Bitmap bg = Bitmap.createBitmap(720, 1280, Bitmap.Config.ARGB_8888); //Setting the Bitmap as background for the ImageView ImageView i = (ImageView) findViewById(R.id.imageView); i.setBackgroundDrawable(new BitmapDrawable(bg)); //Creating the Canvas Object Canvas canvas = new Canvas(bg); //Creating the Paint Object and set its color & TextSize Paint paint = new Paint(); paint.setColor(Color.BLUE); paint.setTextSize(50); //To draw a Rectangle canvas.drawText("Rectangle", 420, 150, paint); canvas.drawRect(400, 200, 650, 700, paint); //To draw a Circle canvas.drawText("Circle", 120, 150, paint); canvas.drawCircle(200, 350, 150, paint); //To draw a Square canvas.drawText("Square", 120, 800, paint); canvas.drawRect(50, 850, 350, 1150, paint); //To draw a Line canvas.drawText("Line", 480, 800, paint); canvas.drawLine(520, 850, 520, 1150, paint); } }
- So now the Coding part is also completed.
- Now run the application to see the output.
Output:
Result:
Thus a Simple Android Application that draws basic Graphical Primitives on the screen is developed and executed successfully.