עקרונות תכנות מונחה עצמים תרגול 6 - GUI

סיכום ביניים GUI:  Swing  Basic components  Event handling  Containers  Layouts

Outline  Game of Life  Painting

Case Study Game of Life

Conway’s Game of Life

Basic Rules  Each cell in the grid is either live or dead  The user determines the initial positions of all live cells.  The game proceeds in rounds. In each round some new organisms born, and others die, according to predefined evolution rules.

Neighbors  The neighbors of a cell are the cells that surround it.

Neighbors  The neighbors of a cell are the cells that surround it.

Evolution Rules  Any live cell with fewer than two live neighbors dies, as if caused by under-population.  Any live cell with two or three live neighbors lives on to the next generation.  Any live cell with more than three live neighbors dies as if by overcrowding.  Any dead cell with exactly three live neighbors becomes a live cell, as if by reproduction

Program clasess  Game – Main class that creates the graphical user interface.  Board – A class that represents the game board. Holds an array of integers and an array of buttons  ButtonPressed – An ActionListener for setting the initial position MODEL VIEW

Game Class

Board Class

public void next ( ) { int [ ] [ ] lastState = new int [ N +2] [ N +2] ; for(int i = 1 ; i <= N ; i++){ // copy current state to new array. for ( int j =1 ; j <= N ; j++){ lastState [i][j] = array [i-1][j-1]; } } // top and buttom row (i = 0,N+1), left and right culomn(j= 0,N+1) initiate to 0 for ( int i = 0 ; i < N ; i++){ // update current state. for(int j < 1; j <= N ; j++ ){ int count = 0; count = countNeighbors(lastState,i+1,j+1); if(count 3 ){ //check for under-population or overcrowding killCell(i,j); } if(count == 3) { // check for reproduction reviveCell(i,j); } private int countNeighbors(int[][] lastState,int x, int y){ int count = lastState[x-1][y-1] + lastState[x-1][y]+lastState[x-1][y+1] // all 3 neighbors left to current cell + lastState[x][y-1] + lastState[x][y+1] // the cell above current and the cell below + lastState[x+1][y-1] + lastState[x+1][y]+lastState[x+1][y+1] ; // all 3 neighbors left to current cell return count; } private void killCell( int i, int j ){ array [i][j] = 0; buttons [i][j].setIcon( null ); } private void reviveCell( int i, int j ){ array [i][j] = 1; buttons [i][j].setIcon( new ImageIcon( “button.gif” )); } }//end of Board class

ButtonPressed Class