Question

I have been researching and struggling with my code to get a textview to update the score when a “ghost” is touched.

This is my first Android application and so far as i can tell(i added Log.w() to the ontouch but a log is never posted as well as the score not being incremented or even appearing) the onTouch(View v, MotionEvent event) is never called. Below is my code.

package com.cs461.Ian;

//TODO:Add accelerometer support
//TODO:Add Clickable ghosts
//TODO:Add camera background
/*Completed:(As of 2:30am 4/16)
 * Activity launches
 * Ghost appears on screen
 * Ghost will randomly move around the screen
 */

import java.util.Random;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.View;
import android.widget.TextView;

public class CameraActivity extends Activity{

Bitmap g;
Ghost a;
Ghost still;
SurfaceHolder mSurfaceHolder;
boolean firsttime=true;
int draw_x,draw_y,xSpeed,ySpeed,score=0;
TextView t;




@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.game);
    a = new Ghost(getApplicationContext());
    still = new Ghost(getApplicationContext());
    //requestWindowFeature(Window.FEATURE_NO_TITLE);
    a.Initalize(BitmapFactory.decodeResource(getResources(), R.drawable.ghost), 20, 20);
    still.Initalize(BitmapFactory.decodeResource(getResources(), R.drawable.ghost), 120, 120);
    t = (TextView) findViewById(R.id.t);
    t.setText("TEST SCORE TO SEE IF TEXTVIEW SHOWS UP");

    a.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            if (event.getAction() == MotionEvent.ACTION_DOWN){
                score++;
                t.setText("Score: "+score);

            }
            return true;
        }
    });
    still.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            if (event.getAction() == MotionEvent.ACTION_DOWN){
                score++;
                t.setText("Score: "+score);
                Log.w("CLICKED","Clicked on ghost "+score+" times");

            }
            return true;
        }
    });



    setContentView(new Panel(this));
}


class Panel extends View {
    public Panel(Context context) {
        super(context);
    }

    @Override
    public void onDraw(Canvas canvas) {
        //g.Initalise(BitmapFactory.decodeFile("/res/drawable-hdpi/ghost.png"), 200, 150, 5, 5);;
        update(canvas);
        invalidate();
    }

    /*Places ghost on screen and bounces it around in the screen. My phone is apparently only API level 4(the most up to date is 15) so i didn't code it
     *for the accelerometer yet.
     */
    public void update(Canvas canvas) {
        Random rand = new Random();
        if(firsttime){
            draw_x = Math.round(System.currentTimeMillis() % (this.getWidth()*2)) ;
            draw_y = Math.round(System.currentTimeMillis() % (this.getHeight()*2)) ;
            xSpeed = rand.nextInt(10);
            ySpeed = rand.nextInt(10);

            firsttime=false;
        }
         draw_x+=xSpeed;
         draw_y+=ySpeed;
        draw_x = Math.round(System.currentTimeMillis() % (this.getWidth()*2)) ;
        draw_y = Math.round(System.currentTimeMillis() % (this.getHeight()*2)) ;
         if (draw_x>this.getWidth()){
          draw_x = (this.getWidth()*2)-draw_x;
          xSpeed = rand.nextInt(10);
          if(xSpeed >=5)
              xSpeed=-xSpeed;
         }
         if (draw_y>this.getHeight()){
          draw_y = (this.getHeight()*2)-draw_y;
          ySpeed = rand.nextInt(10);
          if(ySpeed >=5)
              ySpeed=-ySpeed;
         }
         g = BitmapFactory.decodeResource(getResources(), R.drawable.ghost);
         canvas.drawBitmap(g, draw_x, draw_y, null);
         still.draw(canvas);
         a.update(canvas);


        }
    }


}

Forgot to add class Ghost:

package com.cs461.Ian;

import java.util.Random;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;

public class Ghost extends View implements View.OnTouchListener{
public Ghost(Context context) {
    super(context);
    // TODO Auto-generated constructor stub
}

private Bitmap mAnimation;
private int mXPos;
private int mYPos;
private Rect mSRectangle;
private int mSpriteHeight;
private int mSpriteWidth;
View v;
Rect dest;
int score = 0;

/*public Ghost() {
    mSRectangle = new Rect(0,0,0,0);
    mXPos = 80;
    mYPos = 200;
}*/



public void Initalize(Bitmap theBitmap, int Height, int Width) {
    mSRectangle = new Rect(0,0,0,0);
    mXPos = 80;
    mYPos = 200;
    mAnimation = theBitmap;
    mSpriteHeight = Height;
    mSpriteWidth = Width;
    mSRectangle.top = 0;
    mSRectangle.bottom = mSpriteHeight;
    mSRectangle.left = 0;
    mSRectangle.right = mSpriteWidth;
    dest = new Rect(mXPos, mYPos, mXPos + mSpriteWidth,
            mYPos + mSpriteHeight);

}
public void draw(Canvas canvas) {


    canvas.drawBitmap(mAnimation, mXPos, mYPos, null);
}

public void update(Canvas canvas) {
    new Random();

    mXPos = Math.round(System.currentTimeMillis() % (canvas.getWidth()*2)) ;
    mYPos = Math.round(System.currentTimeMillis() % (canvas.getHeight()*2)) ;
    if (mXPos>canvas.getWidth())
      mXPos = (canvas.getWidth()*2)-mXPos;
    if (mYPos>canvas.getHeight())
      mYPos = (canvas.getHeight()*2)-mYPos;

     draw(canvas);


}

public Rect getRect() {
    return mSRectangle;
}
@Override
public boolean onTouch(View v, MotionEvent event) {
    score++;
    //CameraActivity.t.setText("Score: "+CameraActivity.score);
    Log.w("CLICKED","Clicked on ghost "+score+" times");
    return true; //doesn't work if returns false either
}


}

Answer 1

Override dispatchTouchEvent(MotionEvent event) in your Activity to handle all the touch events that may occur. Return false to pass down the MotionEvent to the next view\layout in the hierachy if they they handle events.