Android games-Sudoku (2)

Android games-Sudoku (2)
> First, create a View class --> inherit SurfaceView and implement SurfaceHolder. callback interface --> SurfaceView. getHolder () obtains the SurfaceHolder object --> SurfaceHolder. addCallback (callback) adds a callback function --> SurfaceHolder. lockCanvas () Get the Canvas object and lock the Canvas --> Canvas painting --> SurfaceHolder. unlockCanvasAndPost (Canvas canvas) ends locking and submits changes to display the image. Public class GameSFView extends SurfaceView implements Callback {private SurfaceHolder surfaceHolder; private int selectedX = 0; private int selectedY = 0;/*** cell width */private float width; /*** cell height */private float height;/*** main. the surfaceview class constructor referenced in xml must use two form parameters */public GameSFView (Context context, AttributeSet attrs) {super (context, attrs); surfaceHolder = this. getHolder (); // get S UrfaceHolder object // listens to the life cycle of the Surface to give the current owner of SurfaceView a callback object. SurfaceHolder. addCallback (this); // Add callback} implement three callback functions // The @ Override public void surfaceChanged (SurfaceHolder holder, int format, int width, int height) {}// triggered during creation. Generally, the drawing thread is called here. // It is best to enable the drawing thread when the Surface is created. // The Sub-thread plot is cached to the surface @ Override public void surfaceCreated (SurfaceHolder holder) {draw () ;}// triggered upon destruction, generally, the drawing thread is stopped and released here. // It is best to destroy the drawing thread @ Override public void surfaceDestroyed (SurfaceHolder holder) when the Surface is destroyed) {} custom drawing method/*** custom Drawing Method */public void draw () {synchronized (surfaceHolder) {// get the Canvas object // lock the Canvas, generally, after locking the image, you can use its returned Canvas object to draw images on it. Canvas canvas = null; Paint paint = new Paint (); try {canvas = surfaceHolder. lockCanvas (); // lock the Canvas // clear the screen painting background initGameView (canvas, paint); // repaint surfaceview to fill in the new data inflateNewNum (canvas, paint );} catch (Exception e) {e. printStackTrace ();} finally {if (canvas! = Null) // Stop locking the drawing and submit the changes. SurfaceHolder. unlockCanvasAndPost (canvas); // unlock Canvas, update }} it is best to use a synchronization lock and use try catch finally for exception capture. Private void initGameView (Canvas canvas, Paint paint) {// bgBitmap = BitmapFactory. decodeResource (getResources (), R. drawable. background); // initialize the game background initGameBg (canvas, paint); // initialize the game line initGameLine (canvas, paint); // initialize the game data initFirstNumber (canvas, paint );} draw the private void initGameLine (Canvas canvas, Paint paint) on the checker {// set the paint color. setColor (Color. BLACK); // draw a horizontal line for (int I = 1; I <10; I ++) {canvas. drawLine (0, I * height, getWidth (), I * height, paint);} // draw a vertical line for (int I = 1; I <9; I ++) {canvas. drawLine (I * height, 0, I * height, getWidth (), paint);} // draw three horizontal and coarse line paints. setStrokeWidth (4); for (int I = 1; I <4; I ++) {canvas. drawLine (0, I * height * 3, getWidth (), I * height * 3, paint);} // draw three vertical and coarse lines for (int I = 1; I <9; I ++) {canvas. drawLine (I * height * 3, 0, I * height * 3, getWidth (), paint );}}