為什么繪制時Log.i沒有在drawCourt（）方法下記錄任何內容（位於SquashCourtView類下）？

Question

為什么繪制時Log.i沒有在drawCourt（）方法下記錄任何內容（位於SquashCourtView類下）？ 我只能在updateCourt（）下看到Log.i結果； 方法。 我試圖記錄每一個步驟，以更好地了解這個簡單的游戲在后台的工作方式。

包com.packetpub.retrosquash;

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.app.Activity;
import android.content.Context;
import android.content.res.AssetFileDescriptor;
import android.content.res.AssetManager;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Point;
import android.media.AudioManager;
import android.media.SoundPool;
import android.os.Bundle;
import android.view.Display;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import java.io.IOException;
import java.util.Random;

public class MainActivity extends Activity {

    Canvas canvas;
    SquashCourtView squashCourtView;
    //Sound
    //initialize sound variables

    private SoundPool soundPool;
    int sample1 = -1;
    int sample2 = -1;
    int sample3 = -1;
    int sample4 = -1;
    //For getting display details like the number of pixels
    Display display;
    Point size;
    int screenWidth;
    int screenHeight;
    //Game objects
    int racketWidth;
    int racketHeight;
    Point racketPosition;
    Point ballPosition;
    int ballWidth;
    //for ball movement
    boolean ballIsMovingLeft;
    boolean ballIsMovingRight;
    boolean ballIsMovingUp;
    boolean ballIsMovingDown;
    //for racket movement
    boolean racketIsMovingLeft;
    boolean racketIsMovingRight;
    //stats
    long lastFrameTime;
    int fps;
    int score;
    int lives;






    @Override
    protected void onCreate(Bundle savedInstanceState)
    {

        Log.i("Step 1: onCreate ", "");


        super.onCreate(savedInstanceState);
        //setContentView(R.layout.activity_main);

        squashCourtView = new SquashCourtView(this);
        setContentView(squashCourtView);



        //Sound code

        soundPool = new SoundPool(10,
                AudioManager.STREAM_MUSIC, 0);

        Log.i("Step 1: onCreate  ", " Loading Music Files");
        try {
            //Create objects of the 2 required classes
            AssetManager assetManager = getAssets();
            AssetFileDescriptor descriptor;
            //create our three fx in memory ready for use
            descriptor =
                    assetManager.openFd("sample1.ogg");
            sample1 = soundPool.load(descriptor, 0);
            descriptor =
                    assetManager.openFd("sample2.ogg");
            sample2 = soundPool.load(descriptor, 0);
            descriptor =
                    assetManager.openFd("sample3.ogg");

            sample3 = soundPool.load(descriptor, 0);
            descriptor =
                    assetManager.openFd("sample4.ogg");
            sample4 = soundPool.load(descriptor, 0);
        } catch (IOException e) {  }





            //Could this be an object with getters and setters
            //Don't want just anyone changing screen size.
            //Get the screen size in pixels
        Log.i("Step 1: onCreate  ", " Getting Display Size");
            display = getWindowManager().getDefaultDisplay();
        Log.i("Step 1: onCreate  ", " display = " + display);
            size = new Point();
            display.getSize(size);
        Log.i("Step 1: onCreate  ", " display.getSize(size) = " + display);
            screenWidth = size.x;
        Log.i("Step 1: onCreate  ", " screenWidth = " + screenWidth);
            screenHeight = size.y;
        Log.i("Step 1: onCreate  ", " screenHeight = " + screenHeight);
            //The game objects
            racketPosition = new Point();
        Log.i("Step 1: onCreate  ", " racketPosition = " + racketPosition);
            racketPosition.x = screenWidth / 2;
        Log.i("Step 1: onCreate  ", " racketPosition.x = " + racketPosition.x);
            racketPosition.y = screenHeight - 45;
        Log.i("Step 1: onCreate  ", " racketPosition.y = " + racketPosition.y);
            racketWidth = screenWidth / 8;
        Log.i("Step 1: onCreate  ", " racketWidth = " + racketWidth);
            racketHeight = 10;
        Log.i("Step 1: onCreate  ", " racketHeight = " + racketHeight);
            ballWidth = screenWidth / 35;
        Log.i("Step 1: onCreate  ", " ballWidth = " + ballWidth);

            ballPosition = new Point();
        Log.i("Step 1: onCreate  ", " ballPosition = " + ballPosition);
            ballPosition.x = screenWidth / 2;
        Log.i("Step 1: onCreate  ", " ballPosition.x = " + ballPosition.x);
            ballPosition.y = 1 + ballWidth;
        Log.i("Step 1: onCreate  ", " ballPosition.y = " + ballPosition.y);
            lives = 3;
        Log.i("Step 1: onCreate  ", " lives= " + lives);



    }




    class SquashCourtView extends SurfaceView implements Runnable
    {



        Thread ourThread = null;
        SurfaceHolder ourHolder;
        volatile boolean playingSquash;
        Paint paint;




        public SquashCourtView(Context context) {
            super(context);

            Log.i("Step 2/1: SCourtView: ", " SquashCourtView(Context context)");
            ourHolder = getHolder();
            Log.i("Step 2/1: SCourtView: ", " ourHolder" + ourHolder);
            paint = new Paint();
            Log.i("Step 2/1: SCourtView: ", " paint = " + paint);
            ballIsMovingDown = true;
            Log.i("Step 2: SCourtView:", " ballIsMovingDown = " + ballIsMovingDown);


            //Send the ball in random direction

            Log.i("Step 2/1: SCourtView:", " Send the ball in random direction");

            Random randomNumber = new Random();
            Log.i("Step 2/1: SCourtView: ", " randomNumber = " + randomNumber);
            int ballDirection = randomNumber.nextInt(3);
            Log.i("Step 2/1: SCourtView: ", " ballDirection  = " + ballDirection);
            switch (ballDirection) {
                case 0:
                    Log.i("Step 2: Switch: ", " Case 0");
                    ballIsMovingLeft = true;
                    ballIsMovingRight = false;
                    Log.i("Step 2: Switch: ", " ballIsMovingLeft  = " + ballIsMovingLeft);
                    Log.i("Step 2: Switch: ", " ballIsMovingRight  = " + ballIsMovingRight);
                    break;
                case 1:
                    Log.i("Step 2/1: Switch:  ", " Case 1");
                    ballIsMovingRight = true;
                    ballIsMovingLeft = false;
                    Log.i("Step 2/1: Switch: ", " ballIsMovingLeft  = " + ballIsMovingLeft);
                    Log.i("Step 2/1: Switch: ", " ballIsMovingRight  = " + ballIsMovingRight);
                    break;
                case 2:
                    Log.i("Step 2/1: Switch:  ", " Case 2");
                    ballIsMovingLeft = false;
                    ballIsMovingRight = false;
                    Log.i("Step 2/1: Switch: ", " ballIsMovingLeft  = " + ballIsMovingLeft);
                    Log.i("Step 2/1: Switch: ", " ballIsMovingRight  = " + ballIsMovingRight);
                    break;
            }
        }

        @Override
        public void run()
        {

            Log.i("Step 2/2: Run:", " ");

            while (playingSquash) {

                Log.i("Step 2/2: Run: ", "While loop (playingSquash)  = " + playingSquash);

                drawCourt();
                updateCourt();
                controlFPS();


            }
        }


        public void updateCourt()
        {

            Log.i("Step 2/2/1:updateC: ", "");
            Log.i("Step 2/2/1:updateC: ", "racketIsMovingRight = " + racketIsMovingRight);
            Log.i("Step 2/2/1:updateC: ", "racketIsMovingLeft = " + racketIsMovingLeft);



            if (racketIsMovingRight) {
                racketPosition.x = racketPosition.x + 10;

                Log.i("Step 2/2/1:updateC: ", "1- IF");
                Log.i("Step 2/2/1:updateC: ", "if (racketIsMovingRight) = True");
                Log.i("Step 2/2/1:updateC: ", "racketPosition.x + 10 = " + racketPosition.x );

            }
            if (racketIsMovingLeft) {
                racketPosition.x = racketPosition.x - 10;

                Log.i("Step 2/2/1:updateC: ", " 2- IF");
                Log.i("Step 2/2/1:updateC: ", "if (racketIsMovingLeft) = True");
                Log.i("Step 2/2/1:updateC: ", "racketPosition.x - 10 = " + racketPosition.x );
            }
            //detect collisions

            Log.i("Step 2/2/1:updateC: ", " detect collisions");

            //hit right of screen



            if (ballPosition.x + ballWidth > screenWidth) {
                ballIsMovingLeft = true;
                ballIsMovingRight = false;
                soundPool.play(sample1, 1, 1, 0, 0, 1);

                Log.i("Step 2/2/1:updateC: ", " 3- IF - hit right of screen");
                Log.i("Step 2/2/1:updateC: ", "if ballPosition.x + ballWidth > screenWidth ");
                Log.i("Step 2/2/1:updateC: ", "ballPosition.x = " + ballPosition.x);
                Log.i("Step 2/2/1:updateC: ", "ballWidth = " + ballWidth);
                Log.i("Step 2/2/1:updateC: ", "screenWidth= " + screenWidth);
                Log.i("Step 2/2/1:updateC: ", "ballIsMovingLeft= " + ballIsMovingLeft);
                Log.i("Step 2/2/1:updateC: ", "ballIsMovingRight= " + ballIsMovingRight);


            }
            //hit left of screen
            if (ballPosition.x < 0) {
                ballIsMovingLeft = false;
                ballIsMovingRight = true;
                soundPool.play(sample1, 1, 1, 0, 0, 1);

                Log.i("Step 2/2/1:updateC: ", " 4- IF - hit Left of screen");
                Log.i("Step 2/2/1:updateC: ", "if ballPosition.x < 0 ");
                Log.i("Step 2/2/1:updateC: ", "ballPosition.x = " + ballPosition.x);
                Log.i("Step 2/2/1:updateC: ", "ballIsMovingLeft= " + ballIsMovingLeft);
                Log.i("Step 2/2/1:updateC: ", "ballIsMovingRight= " + ballIsMovingRight);
            }
            //Edge of ball has hit bottom of screen




           if (ballPosition.y > screenHeight - ballWidth)



            //if (ballPosition.y > screenHeight)

           {
               Log.i("Step 2/2/1:updateC: ", " Edge of ball has hit bottom of screen");
               Log.i("Step 2/2/1:updateC: ", " LookLook  **************************");
               Log.i("Step 2/2/1:updateC: ", " 5- IF - Edge of ball has hit bottom of screen");
                Log.i("Step 2/2/1:updateC: ", "if (ballPosition.y > screenHeight - ballWidth) ");
                Log.i("Step 2/2/1:updateC: ", "ballPosition.y = " + ballPosition.y);
                Log.i("Step 2/2/1:updateC: ", "screenHeight= " + screenHeight);
                Log.i("Step 2/2/1:updateC: ", "ballWidth= " + ballWidth);
               Log.i("Step 2/2/1:updateC: ", "if "  + ballPosition.y + " > " +  (screenHeight - ballWidth));
                lives = lives - 1;
                Log.i("Step 2/2/1:updateC: ", "lives - 1= " + lives);


                if (lives == 0)
                {
                    Log.i("Step 2/2/1:updateC: ", "5/1 -  IF= ");
                    Log.i("Step 2/2/1:updateC: ", "if (lives == 0");
                    lives = 3;
                    score = 0;
                    soundPool.play(sample4, 1, 1, 0, 0, 1);
                    Log.i("Step 2/2/1:updateC: ", "lives = " + lives);
                    Log.i("Step 2/2/1:updateC: ", "score = " + score);
                }



                Log.i("Step 2/2/1:updateC: ", "End of IF 5 - maybe an else");
                Log.i("Step 2/2/1:updateC: ", "back to top of screen");
                Log.i("Step 2/2/1:updateC: ", "ballPosition.y = 1 + ballWidth");
                ballPosition.y = 1 + ballWidth;//back to top of screen

                Log.i("Step 2/2/1:updateC: ", "ballPosition.y = " + ballPosition.y);
                Log.i("Step 2/2/1:updateC: ", "ballWidth = " + ballWidth);
                //what horizontal direction should we use
                //for the next falling ball


                Log.i("Step 2/2/1:updateC: ", "End of all IFs");
                Log.i("Step 2/2/1:updateC: ", "what horizontal direction should we use for the next falling ball ");


                Random randomNumber = new Random();
                Log.i("Step 2/2/1:updateC: ", "randomNumber = " + randomNumber);

                int startX = randomNumber.nextInt(screenWidth - ballWidth) + 1;
                Log.i("Step 2/2/1:updateC: ", "startX = " + startX);
                ballPosition.x = startX + ballWidth;
                Log.i("Step 2/2/1:updateC: ", "ballPosition.x (startX + ballWidth) = " + ballPosition.x);

                int ballDirection = randomNumber.nextInt(3);
                Log.i("Step 2/2/1:updateC: ", "switch (ballDirection) = " + ballDirection);
                switch (ballDirection) {

                    case 0:
                        ballIsMovingLeft = true;
                        ballIsMovingRight = false;
                        Log.i("Step 2/2/1:switch: ", "Case 0");
                        Log.i("Step 2/2/1:switch: ", "ballIsMovingLeft = " + ballIsMovingLeft);
                        Log.i("Step 2/2/1:switch: ", "ballIsMovingRight = " + ballIsMovingRight);
                        break;
                    case 1:
                        ballIsMovingRight = true;
                        ballIsMovingLeft = false;
                        Log.i("Step 2/2/1:switch: ", "Case 1");
                        Log.i("Step 2/2/1:switch: ", "ballIsMovingLeft = " + ballIsMovingLeft);
                        Log.i("Step 2/2/1:switch: ", "ballIsMovingRight = " + ballIsMovingRight);
                        break;
                    case 2:
                        ballIsMovingLeft = false;
                        ballIsMovingRight = false;
                        Log.i("Step 2/2/1:switch: ", "Case 2");
                        Log.i("Step 2/2/1:switch: ", "ballIsMovingLeft = " + ballIsMovingLeft);
                        Log.i("Step 2/2/1:switch: ", "ballIsMovingRight = " + ballIsMovingRight);
                        break;
                }


            }


            //we hit the top of the screen
            if (ballPosition.y <= 0) {
                ballIsMovingDown = true;
                ballIsMovingUp = false;
                ballPosition.y = 1;
                soundPool.play(sample2, 1, 1, 0, 0, 1);

                Log.i("Step 2/2/1:updateC: ", " 6- IF - we hit the top of the screen");
                Log.i("Step 2/2/1:updateC: ", "if (ballPosition.y <= 0)");
                Log.i("Step 2/2/1:updateC: ", "ballIsMovingDown = " + ballIsMovingDown);
                Log.i("Step 2/2/1:updateC: ", "ballPosition.y = " + ballPosition.y );

            }
            //depending upon the two directions we should
            //be moving in adjust our x any positions
            if (ballIsMovingDown) {ballPosition.y += 6;

                Log.i("Step 2/2/1:updateC: ", " 7- IF - depending upon the two directions we should be moving in adjust our x any positions");
                Log.i("Step 2/2/1:updateC: ", "(ballIsMovingDown) ballPosition.y += 6;");
                Log.i("Step 2/2/1:updateC: ", "ballIsMovingDown = " + ballIsMovingDown);
                Log.i("Step 2/2/1:updateC: ", "ballPosition.y = " + ballPosition.y );
            }
            if (ballIsMovingUp) {ballPosition.y -= 10;
                Log.i("Step 2/2/1:updateC: ", " 8- IF - depending upon the two directions we should be moving in adjust our x any positions");
                Log.i("Step 2/2/1:updateC: ", "if (ballIsMovingUp) {ballPosition.y -= 10;");
                Log.i("Step 2/2/1:updateC: ", "ballIsMovingDown = " + ballIsMovingDown);
                Log.i("Step 2/2/1:updateC: ", "ballPosition.y = " + ballPosition.y );
            }
            if (ballIsMovingLeft) {ballPosition.x -= 12;
                Log.i("Step 2/2/1:updateC: ", " 9- IF - depending upon the two directions we should be moving in adjust our x any positions");
                Log.i("Step 2/2/1:updateC: ", "if (ballIsMovingLeft) {ballPosition.x -= 12;");
                Log.i("Step 2/2/1:updateC: ", "ballIsMovingLeft = " + ballIsMovingLeft);
                Log.i("Step 2/2/1:updateC: ", "ballPosition.y = " + ballPosition.y );
            }
            if (ballIsMovingRight) {ballPosition.x += 12;
                Log.i("Step 2/2/1:updateC: ", " 10- IF - depending upon the two directions we should be moving in adjust our x any positions");
                Log.i("Step 2/2/1:updateC: ", " if (ballIsMovingRight) {ballPosition.x += 12;");
                Log.i("Step 2/2/1:updateC: ", "ballIsMovingRight = " + ballIsMovingRight);
                Log.i("Step 2/2/1:updateC: ", "ballPosition.y = " + ballPosition.y );
            }

            //Has ball hit racket?

            //if (ballPosition.y + ballWidth >= (racketPosition.y - racketHeight / 2))


            if ((ballPosition.y + ballWidth) - 45>= (racketPosition.y))
            //if (ballPosition.y + ballWidth >= (screenHeight - 200))
            {

                Log.i("Step 2/2/1:updateC: ", " 11- IF -  ball hit the racket");
                Log.i("Step 2/2/1:updateC: ", " if (ballPosition.y >= (racketPosition.y))");
                Log.i("Step 2/2/1:updateC: ", "ballPosition.y = " + ballPosition.y );
                Log.i("Step 2/2/1:updateC: ", "racketPosition.y = " + racketPosition.y );
                Log.i("Step 2/2/1:updateC: ", "ballWidth = " + ballWidth);
                Log.i("Step 2/2/1:updateC: ", " if " + (ballPosition.y) + ">=" + (racketPosition.y));


               int halfRacket = racketWidth / 2;
                Log.i("Step 2/2/1:updateC: ", "halfRacket = " + halfRacket);
                if (ballPosition.x + ballWidth > (racketPosition.x - halfRacket) && ballPosition.x - ballWidth < (racketPosition.x + halfRacket))



                {
                    //rebound the ball vertically and play a sound
                    Log.i("Step 2/2/1:updateC: "," rebound the ball vertically and play a sound");
                    soundPool.play(sample3, 1, 1, 0, 0, 1);
                    score++;
                    ballIsMovingUp = true;
                    ballIsMovingDown = false;
                    Log.i("Step 2/2/1:updateC: ", "score++ = " + score);
                    Log.i("Step 2/2/1:updateC: ", "ballIsMovingUp = " + ballIsMovingUp);
                    Log.i("Step 2/2/1:updateC: ", "ballIsMovingDown =" + ballIsMovingDown);

                    Log.i("Step 2/2/1:updateC: ", " 11/1-  rebound the ball vertically and play a sound");
                    Log.i("Step 2/2/1:updateC: "," if (ballPosition.x + ballWidth > (racketPosition.x - halfRacket) && ballPosition.x - ballWidth < (racketPosition.x + halfRacket))");
                    Log.i("Step 2/2/1:updateC: ", "ballPosition.x = " + ballPosition.x );
                    Log.i("Step 2/2/1:updateC: ", "ballWidth = " + ballWidth);
                    Log.i("Step 2/2/1:updateC: ", "racketPosition.x = " + racketPosition.x );
                    Log.i("Step 2/2/1:updateC: ", "halfRacket = " + halfRacket);
                    Log.i("Step 2/2/1:updateC: ", "if " + (ballPosition.x + ballWidth) + " > " + (racketPosition.x - halfRacket) + " && " + (ballPosition.x - ballWidth) + " < " + (racketPosition.x + halfRacket));


                    //now decide how to rebound the ball horizontally
                    if (ballPosition.x > racketPosition.x)
                    {
                        Log.i("Step 2/2/1:updateC: ", " 11/1/1 If- now decide how to rebound the ball horizontally");

                        ballIsMovingRight = true;
                        ballIsMovingLeft = false;
                        Log.i("Step 2/2/1:updateC: ", "ballIsMovingRight = " + ballIsMovingRight);
                        Log.i("Step 2/2/1:updateC: ", "ballIsMovingLeft = " + ballIsMovingLeft);
                    } else
                    {
                        Log.i("Step 2/2/1:updateC: ", " 11/1/1 Else- now decide how to rebound the ball horizontally");
                        ballIsMovingRight = false;
                        ballIsMovingLeft = true;
                        Log.i("Step 2/2/1:updateC: ", "ballIsMovingRight = " + ballIsMovingRight);
                        Log.i("Step 2/2/1:updateC: ", "ballIsMovingLeft = " + ballIsMovingLeft);
                    }
                }
            }

        }


        public void drawCourt() {

            Log.i("Step 2/2/2:drawCourt: ", "");

            if (ourHolder.getSurface().isValid()) {
                canvas = ourHolder.lockCanvas();
                //Paint paint = new Paint();
                canvas.drawColor(Color.BLACK);//the background
                Log.i("Step 2/2/2:drawCourt: ", "");
                paint.setColor(Color.argb(255, 255, 255, 255));
                paint.setTextSize(45);
                canvas.drawText("Score:" + score + " Lives:" + lives + " fps: " + fps, 20, 40, paint);
                //Draw the squash racket
                Log.i("Step 33:drawCourt: ", "");
                canvas.drawRect(racketPosition.x - (racketWidth / 2), racketPosition.y - (racketHeight / 2), racketPosition.x + (racketWidth / 2), racketPosition.y + racketHeight, paint);
                //canvas.drawRect(racketPosition.x - (racketWidth / 2), screenHeight - 200, racketPosition.x + (racketWidth / 2), screenHeight - 190, paint);
                //canvas.drawRect(racketPosition.x - (racketWidth / 2),1100, racketPosition.x + (racketWidth / 2),1110, paint);
                //canvas.drawRect(336,1000,432,1174, paint);

//                int a = (racketPosition.x - (racketWidth / 2));
//                int b = racketPosition.y - (racketHeight / 2);
//                int c = racketPosition.x + (racketWidth / 2);
//                int d = racketPosition.y + racketHeight;


                //canvas.drawRect(a,b,c,d, paint);

                //Draw the ball
                canvas.drawRect(ballPosition.x, ballPosition.y, ballPosition.x + ballWidth, ballPosition.y + ballWidth, paint);
                Log.i("Step 2/2/2:drawCourt: ", "");
                ourHolder.unlockCanvasAndPost(canvas);
                Log.i("Step 2/2/2:drawCourt: ", "");
            }


        }


        public void controlFPS() {

            Log.i("Step 2/2/2:controlFPS: ", "");

            long timeThisFrame =
                    (System.currentTimeMillis() - lastFrameTime);
            long timeToSleep = 15 - timeThisFrame;
            if (timeThisFrame > 0) {
                fps = (int) (1000 / timeThisFrame);
            }
            if (timeToSleep > 0) {
                try {
                    ourThread.sleep(timeToSleep);
                } catch (InterruptedException e) {
                }
            }
            lastFrameTime = System.currentTimeMillis();
        }

        public void pause()
        {


            playingSquash = false;
            try {
                ourThread.join();
            } catch (InterruptedException e) {
            }
        }


        public void resume()
        {

            playingSquash = true;
            ourThread = new Thread(this);
            ourThread.start();


        }

    }





    @Override
    public boolean onTouchEvent(MotionEvent motionEvent)
    {

        switch (motionEvent.getAction() &
                MotionEvent.ACTION_MASK) {
            case MotionEvent.ACTION_DOWN:
                if (motionEvent.getX() >= screenWidth /
                        2) {
                    racketIsMovingRight = true;
                    racketIsMovingLeft = false;
                } else {
                    racketIsMovingLeft = true;
                    racketIsMovingRight = false;
                }
                break;
            case MotionEvent.ACTION_UP:
                racketIsMovingRight = false;
                racketIsMovingLeft = false;
                break;
        }
        return true;


    }


    @Override
    protected void onStop() {


        super.onStop();
        while (true) {
            squashCourtView.pause();
            break;
        }
        finish();
    }


    @Override
    protected void onPause() {


        super.onPause();
        squashCourtView.pause();
    }

    @Override
    protected void onResume() {


        super.onResume();
        squashCourtView.resume();
    }

    public boolean onKeyDown(int keyCode, KeyEvent event) {


        if (keyCode == KeyEvent.KEYCODE_BACK) {
            squashCourtView.pause();
            finish();
            return true;
        }
        return false;


    }
}

Answer 1

問題在這里： Log.i("Step 2/2/2:drawCourt: ", "");

Log.i(tag, msg)有兩個參數。

標簽 -用於標識日志消息的來源。 它通常標識發生日志調用的類或活動。
msg-您想要記錄的消息。

tag是找到日志起源的方法。 如果您的msg為空，則日志中將不會顯示任何內容。 因此，這不會記錄。 因此，要記錄Log.i或Log.d等，您需要具有一個非空的msg 。