2019.10.28

MainActivity.java

package edu.byuh.cis.cs203.hellocs203.sys;

import android.app.Activity;
import android.os.Bundle;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        LetiView lv = new LetiView(this);
        setContentView(lv);
    }
}

LetiView.java

package edu.byuh.cis.cs203.hellocs203.sys;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

import edu.byuh.cis.cs203.hellocs203.graphics.Duck;

public class LetiView extends View {

    //private Duck donald;
    private List<Duck> flock;
    private boolean init;
    private Paint bluePaint;
    private Paint pinkPaint;



    public /*static*/ class Timer extends Handler {

        public Timer() {
            sendMessageDelayed(obtainMessage(), 0);
        }

        @Override
        public void handleMessage(Message m) {
            //Log.d("CS203", "Hello, Altair!");
            //donald.dance();
            for (Duck d : flock) {
                d.dance();
            }
            invalidate();
            sendMessageDelayed(obtainMessage(), 100);
        }
    }


    public LetiView(Context c) {
        super(c);
        init = false;
        //donald = new Duck(getResources());
        flock = new ArrayList<>();
        Toast t = Toast.makeText(c, "This is another factory example!", Toast.LENGTH_LONG);
        t.show();
        bluePaint = new Paint();
        bluePaint.setColor(Color.BLUE);
        bluePaint.setStyle(Paint.Style.FILL);
        bluePaint.setTextSize(60);
        bluePaint.setTextAlign(Paint.Align.CENTER);
        pinkPaint = new Paint();
        pinkPaint.setColor(Color.rgb(255, 200, 200));
        Timer tim = new Timer();
}

    private void makeDucks(int n) {
        for (int i=0; i<n; i++) {
            flock.add(new Duck(getResources()));
        }
        float w = getWidth();
        float h = getHeight();
        for (Duck d : flock) {
            d.resize(w);
            float x = (float)(Math.random()*(w-d.width()));
            float y = (float)(Math.random()*(h-d.height()));
            d.setPosition(x,y);
        }
    }

    @Override
    public void onDraw(Canvas c) {
        float w = c.getWidth();
        float h = c.getHeight();
        if (init == false) {
            //donald.resize(w);
            //donald.setPosition(w/2, h/2);
            makeDucks(5);
            bluePaint.setStrokeWidth(w/50);
            init = true;
        }
        c.drawColor(Color.GREEN);
        c.drawRect(w/10, h/10, w*0.3f, h*0.4f, bluePaint);
        c.drawLine(w*0.8f, h*0.5f, w*0.5f, h*0.7f, bluePaint);
        c.drawCircle(w*0.3f, h*0.8f, w*0.1f, pinkPaint);
        c.drawText("General Conference was great!", w/2, h/2, bluePaint);
        //donald.draw(c);
        for (Duck d : flock) {
            d.draw(c);
        }
    }

    @Override
    public boolean onTouchEvent(MotionEvent m) {

        //this is a "local class"!
        //its scope is limited just to the onTouchEvent method.
        //it is invisible to all other methods in LetiView.
        /*class ClickOK implements DialogInterface.OnClickListener {

            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
                makeDucks(5);
            }
        }*/

        float x = m.getX();
        float y = m.getY();
        if (m.getAction() == MotionEvent.ACTION_DOWN) {
            //Log.d("CS203", "You just tapped at (" + x + "," + y + ")!");
            List<Duck> doomed = new ArrayList<>();
            for (Duck d : flock) {
                if (d.contains(x,y)) {
                    //flock.remove(d);
                    //break;
                    doomed.add(d);
                }
            }
            for (Duck d : doomed) {
                flock.remove(d);
            }
            if (flock.isEmpty()) {
                //ClickOK ivan = new ClickOK();
                AlertDialog.Builder ab = new AlertDialog.Builder(getContext());
                ab.setTitle("Duck World 3000")
                  .setMessage("Congratulations Captain! You have cleared the sector of all the ducks that were threatening our way of life. The federation is in need of a captain for a similar mission. Any volunteers?")
                  .setCancelable(false)
                  .setPositiveButton("Yes, sign me up!", (d, i) -> makeDucks(5))
                  .setNegativeButton("No, I'm done.", new DialogInterface.OnClickListener() {
                      @Override
                      public void onClick(DialogInterface dialogInterface, int i) {
                          Activity parent = (Activity)getContext();
                          parent.finish();
                      }
                  });
                AlertDialog box = ab.create();
                box.show();
            }
        }
        return true;
    }

}

Duck.java

package edu.byuh.cis.cs203.hellocs203.graphics;

import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.RectF;

import edu.byuh.cis.cs203.hellocs203.R;

public class Duck {
    private Bitmap image;
    private RectF bounds;

    /**
     * Create a new duck
     * @param res the Android resources object
     */
    public Duck(Resources res) {
        bounds = new RectF();
        image = BitmapFactory.decodeResource(res, R.drawable.duck);
    }

    /**
     * scale the duck to its correct on-screen size
     * @param screenWidth the width of the screen in pixels
     */
    public void resize(float screenWidth) {
        float duckSize = screenWidth * 0.2f;
        image = Bitmap.createScaledBitmap(image,
                (int)duckSize, (int)duckSize, true);
        bounds.set(0,0,duckSize, duckSize);
    }

    /**
     * Draw the duck at its predefined location
     * @param c the Android canvas object
     */
    public void draw(Canvas c) {
        c.drawBitmap(image, bounds.left, bounds.top, null);
    }

    /**
     * Sets the center of the duck to (x,y)
     * @param x the new center x coordinate
     * @param y the new center y coordinate
     */
    public void setPosition(float x, float y) {
        bounds.offsetTo(x,y);
    }

    public float width() {
        return bounds.width();
    }

    public void dance() {
        float dx = 5-(float)(Math.random() * 10);
        float dy = 5-(float)(Math.random() * 10);
        bounds.offset(dx,dy);
    }

    public boolean contains(float x, float y) {
        return bounds.contains(x,y);
    }

    public float height() {
        return bounds.height();
    }
}