如何根据点数组列表画圆？

Question

我正在创建一个测试游戏，其中一个圆圈在被触摸时将移动到点数组列表中的选定位置。但是，单击时似乎无法移动到点的下一个位置。你能帮我找出问题出在哪里以及我可以使用什么解决方案吗？

public class EyeTestActivity extends AppCompatActivity  {

private GestureDetectorCompat mDetector;

@Override

protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,

            WindowManager.LayoutParams.FLAG_FULLSCREEN);

    this.requestWindowFeature(Window.FEATURE_NO_TITLE);

    setContentView(new TestView(this));

    // get the gesture detector

    mDetector = new GestureDetectorCompat(EyeTestActivity.this, new SwipeGestureDetector());

}

public boolean onTouchEvent(MotionEvent motionEvent) {

    this.mDetector.onTouchEvent(motionEvent);

    return super.onTouchEvent(motionEvent);

}

@Override

public boolean dispatchTouchEvent(MotionEvent ev) {

    super.dispatchTouchEvent(ev);

    return mDetector.onTouchEvent(ev);

}

public class TestView extends View {

    public ArrayList<Point> pointlist;

    Paint paint;

    public TestView(Context context) {

        super(context);

        init();

        setFocusable(true);

        setFocusableInTouchMode(true);

        createPointList();

    }

    public void init() {

        paint = new Paint();

        paint.setColor(Color.WHITE);

        paint.setStrokeWidth(5);

        paint.setStyle(Paint.Style.STROKE);

    }

我希望在打印时绘制下一个圆圈。

Answer 1

首先，您应该参考您的TestView布局。public class EyeTestActivity extends AppCompatActivity&nbsp; {&nbsp; &nbsp; private GestureDetectorCompat mDetector;&nbsp; &nbsp; private TestView tv;&nbsp; &nbsp; @Override&nbsp; &nbsp; protected void onCreate(Bundle savedInstanceState) {&nbsp; &nbsp; &nbsp;super.onCreate(savedInstanceState);&nbsp; &nbsp; &nbsp;getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,&nbsp; &nbsp; &nbsp; &nbsp; WindowManager.LayoutParams.FLAG_FULLSCREEN);&nbsp; &nbsp; &nbsp;this.requestWindowFeature(Window.FEATURE_NO_TITLE);&nbsp; &nbsp; &nbsp;tv = new TestView(this);&nbsp; &nbsp; &nbsp;setContentView(tv);&nbsp; &nbsp; &nbsp;// get the gesture detector&nbsp; &nbsp; &nbsp;mDetector = new GestureDetectorCompat(EyeTestActivity.this, new SwipeGestureDetector());}然后，在您的onScroll事件中，您应该测试e2而不是e1@Overridepublic boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {&nbsp; &nbsp; if (e2.getAction() == MotionEvent.ACTION_MOVE) {&nbsp; &nbsp; &nbsp; &nbsp; z++;&nbsp; &nbsp; &nbsp; &nbsp;if (z >= 120) {&nbsp; &nbsp;// zero based arraylist, so, >= 120&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;z = 0;&nbsp; &nbsp; &nbsp; &nbsp;}&nbsp; &nbsp; &nbsp; &nbsp;tv.invalidate; // this to redraw the point&nbsp; &nbsp; }&nbsp; &nbsp; return true;}我认为你createPointList没有做你想做的事。您正在创造 120 次相同的点！总计 120 * 5 * 24 = 14.400 点！它应该是for (int i = 1; i <= 5; i++) {&nbsp; &nbsp; float a = 100 * i;&nbsp; &nbsp; float b = 100 * i;&nbsp; &nbsp; for (int j = 1; j <= 24; j++) {&nbsp; &nbsp; &nbsp; &nbsp; float x = (float) (a * Math.sin(Math.toRadians(15 * j)));&nbsp; &nbsp; &nbsp; &nbsp; float y = (float) (b * Math.cos(Math.toRadians(15 * j)));&nbsp; &nbsp; &nbsp; &nbsp; pointlist.add(new Point((int)x, (int)y));&nbsp; &nbsp; }}