I am writing a solitaire app. I use a canvas to draw everything on the
screen. Sometimes a pile of cards will get big and extend below the
bottom of the screen. I would like to make the canvas scrollable so
the user can access those cards.
Main Activity.
Java:
package com.maulinpathare.solitaire;
public class Solitaire extends Activity{
/** Called when the activity is first created. */
private Context mContext;
private GameView mG;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mContext = this;
setContentView(R.layout.main);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
boolean result = super.onCreateOptionsMenu(menu);
menu.add(0, 1, 0, R.string.newGame);
menu.add(0, 2, 0, R.string.exitGame);
return result;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case 1:
mG = new GameView(this);
setContentView(mG);
return true;
case 2:
finish();
return true;
}
return false;
}
}//end class
GameView Class
This is where everything happens
I have removed most of the game logic…
Java:
package com.maulinpathare.solitaire;
public class GameView extends ScrollView implements OnTouchListener{
private Deck mD;
private boolean mInit, mDone;
private Stack mPile1, mPile2, mPile3, mPile4, mPile5,
mPile6, mPile7,
mOpenPile, mEndPile1, mEndPile2,
mEndPile3, mEndPile4, mTemp;
private Canvas mCanvas;
private int mPile;
private boolean mPickUp, mVictory;
private Card mCard;
private final int mSpacing = 22;
private Paint rectPaint, wonPaint1, wonPaint2;
public GameView(Context context) {
super(context);
//initialize everything needed for the game
}
@Override
protected void onDraw(Canvas canvas) {
mCanvas = canvas;
if(mInit){
initialize();
mInit = false;
}
//draw stuff...
}//end onDraw
public boolean onTouch(View v, MotionEvent event){
int eventAction = event.getAction();
int x = Math.round(event.getX());
int y = Math.round(event.getY());
switch(eventAction){
case MotionEvent.ACTION_DOWN:
//check if touch has happened on one of the card
piles
break; //end case action_touch
case MotionEvent.ACTION_MOVE:
//if card touched move it
break; //end case action_move
case MotionEvent.ACTION_UP:
//check if legal move has been made
break; //end case action_up
}//end switch(event)
invalidate();
return true;
}//end onTouch
}
Where and how should I implement screen scrolling? I would like the
user to be able to slide their finger across the screen in the
direction they want to scroll.