I'm struggeling with following problem: I'm developing a small 2D Adroid game on Eclipse ( I'm a greenhorn). The basic idea is too keep a figure on the screen and when it leaves it , it's Game Over. The basic classes are the GameActivity, the GameView, the Figure and a GameOverActivity. Since my gaming-background is drawn on a simple RecF I check when the figure leaves the screen by
public class Figure{
public RectF getBounds(){
return new RectF(x, y, x + width, y+ height);
}
}
---------------------------------
public class GameView extends SurfaceView {
private GameActivity theGameActivity = new GameActivity();
private RectF figurebounds;
public void checkifout() {
figurebounds = figure.getBounds();
if (!(background.intersect(figurebounds))) {
theGameActivity.GameOver();
}
}
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public class GameActivity extends Activity {
public void GameOver() {
Intent theNextIntent = new Intent(getApplicationContext(), GameOverActivity.class);
startActivity(theNextIntent);
this.finish();
}
}
The GameOverActivity is just a Layout with 2 buttons which allows to get back to the menu or replay
public class GameOverActivity extends Activity implements OnClickListener {
Button bReplay;
Button bBack;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.gameoverscreen);
initialize();
}
public void onClick(View v) {
switch (v.getId()) {
case R.id.bReplay:
Intent newGameScreen= new Intent(this, GameActivity.class);
startActivity(newGameScreen);
this.finish();
break;
case R.id.bBack:
Intent newGameScreen2 = new Intent(this, MenuActivity.class);
startActivity(newGameScreen2);
this.finish();
break;
}
}
public void initialize(){
bReplay = (Button) findViewById(R.id.bReplay);
bReplay.setOnClickListener(this);
bBack = (Button) findViewById(R.id.bBack);
bBack.setOnClickListener(this);
}
At first I had the checkifout()-method within my onTouch-method (which is used to create another figures which have no influence on this issue) in the GameView-class , so I had to touch the screen after the figure fell off to get to the Gameover-screen, but at least it worked all fine:
public boolean onTouchEvent(MotionEvent event) {
if (System.currentTimeMillis() - lastClick > 300) {
lastClick = System.currentTimeMillis();
synchronized (getHolder()) {
xcor = event.getX();
ycor = event.getY();
checkifout();
}
}
return true;
}
But I'd like the GameOver-screen appear without another Touchevent.
Now when I call the checkifout()-method within my draw-method (also within the GameView class):
public void draw(Canvas canvas) {
drawBackGround(canvas);
figure.draw(canvas);
checkifout();
}
I get following problem: When my figure falls off the screen I do get the GameOver-screen, but after about a second it displays another time and when I go back to the main menu and try to exit the game I get back to the GameOverscreen, while replay stills works fine. I don't get those issues when I implement checkifout() in the OnTouchevent...
I thought it might be a problem of calling the checkifout()-method multiple times, so I tried to fix the issue by using a boolean like this :
private boolean gameover = false;
public void draw(Canvas canvas) {
drawBackGround(canvas);
figure.draw(canvas);
if (!gameover)
checkifout();
}
public void checkifout() {
figurebounds = figure.getBounds();
if (!(background.intersect(figurebounds))) {
theGameActivity.GameOver();
gameover=true;
}
But that gave me a NullPointerException.I also tried to create the checkifout-method within the Figure class and call it in the draw-method of the Figure-class, but that caused the same errors. So I hope someone has got an idea or just knows the mistake I've done here. Thanks for taking the time.
PS: Here is the MenuActivity (Layout with 2 buttons) in case it's needed:
public class MenuActivity extends Activity implements OnClickListener {
ImageButton bPlay;
ImageButton bExit;
@Override
public void onClick(View v) {
switch(v.getId()){
case R.id.bPlay:
Intent newGameScreen = new Intent(this, GameActivity.class);
startActivity(newGameScreen);
this.finish();
break;
case R.id.bExit:
this.finish();
break;
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mainmenu);
initialize();
}
public void initialize(){
bPlay = (ImageButton) findViewById(R.id.bPlay);
bPlay.setOnClickListener(this);
bExit = (ImageButton) findViewById(R.id.bExit);
bExit.setOnClickListener(this);
}
}