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使用手指在点之间画线

android
8
我可以使用Android SDK的示例中提供的FingerPaint in API Demos在我的应用程序中用手指画线。但是如何仅沿着屏幕上放置的点用手指绘制这些线条。我想要像此应用程序中的内容：https://play.google.com/store/apps/details?id=zok.android.dots enter image description here 我只想用手指在点1和点2之间绘制一条线。仅当触摸到点2时，才绘制1和2之间的线条，否则不应绘制。同样，从点2到点3等。 请帮我编写这个代码。 先谢谢了！
P.S. 在回答问题之前，请仔细查看链接中的应用程序，以便您对我的要求有一个清晰的了解。
更新：
public class PaintView extends View {

private Bitmap mBitmap;
private Canvas mCanvas;
private Path mPath;
private Paint mPaint;
private static final int TOUCH_TOLERANCE_DP = 20;
private static final int BACKGROUND = 0xFFDDDDDD;
private List<Point> mPoints = new ArrayList<Point>();
private int mLastPointIndex = 0;
private int mTouchTolerance;
private boolean isPathStarted = false;

public PaintView(Context context) {
    super(context);
    mCanvas = new Canvas();
    mPath = new Path();
    mPaint = new Paint();
    mPaint.setAntiAlias(true);
    mPaint.setDither(true);
    mPaint.setColor(Color.BLACK);
    mPaint.setStyle(Paint.Style.STROKE);
    mPaint.setStrokeJoin(Paint.Join.ROUND);
    mPaint.setStrokeCap(Paint.Cap.ROUND);
    mPaint.setStrokeWidth(12);
    mTouchTolerance = dp2px(TOUCH_TOLERANCE_DP);

    // TODO just test points
    Point p1 = new Point(133, 123);
    Point p2 = new Point(149, 136);
    Point p3 = new Point(182, 136);
    Point p4 = new Point(206, 118);
    Point p5 = new Point(208, 87);
    Point p6 = new Point(187, 71);
    Point p7 = new Point(144, 78);
    Point p8 = new Point(124, 101);
    Point p9 = new Point(113, 128);
    Point p10 = new Point(112, 157);
    Point p11 = new Point(119, 188);
    Point p12 = new Point(134, 209);
    Point p13 = new Point(162, 228);
    Point p14 = new Point(194, 238);
    Point p15 = new Point(232, 240);
    Point p16 = new Point(263, 237);
    Point p17 = new Point(289, 224);
    Point p18 = new Point(315, 204);
    Point p19 = new Point(332, 174);
    Point p20 = new Point(339, 128);
    Point p21 = new Point(329, 95);
    Point p22 = new Point(304, 73);
    Point p23 = new Point(280, 69);
    Point p24 = new Point(254, 87);
    Point p25 = new Point(248, 116);
    Point p26 = new Point(259, 143);
    Point p27 = new Point(278, 153);
    Point p28 = new Point(241, 157);
    Point p29 = new Point(192, 160);
    Point p30 = new Point(150, 159);
    mPoints.add(p1);
    mPoints.add(p2);
    mPoints.add(p3);
    mPoints.add(p4);
    mPoints.add(p5);
    mPoints.add(p6);
    mPoints.add(p7);
    mPoints.add(p8);
    mPoints.add(p9);
    mPoints.add(p10);
    mPoints.add(p11);
    mPoints.add(p12);
    mPoints.add(p13);
    mPoints.add(p14);
    mPoints.add(p15);
    mPoints.add(p16);
    mPoints.add(p17);
    mPoints.add(p18);
    mPoints.add(p19);
    mPoints.add(p20);
    mPoints.add(p21);
    mPoints.add(p22);
    mPoints.add(p23);
    mPoints.add(p24);
    mPoints.add(p25);
    mPoints.add(p26);
    mPoints.add(p27);
    mPoints.add(p28);
    mPoints.add(p29);
    mPoints.add(p30);
}

public PaintView(Context context, AttributeSet attrs) {
    super(context, attrs);
    mCanvas = new Canvas();
    mPath = new Path();
    mPaint = new Paint();
    mPaint.setAntiAlias(true);
    mPaint.setDither(true);
    mPaint.setColor(Color.BLACK);
    mPaint.setStyle(Paint.Style.STROKE);
    mPaint.setStrokeJoin(Paint.Join.ROUND);
    mPaint.setStrokeCap(Paint.Cap.ROUND);
    mPaint.setStrokeWidth(12);
    mTouchTolerance = dp2px(TOUCH_TOLERANCE_DP);

    // TODO just test points
    Point p1 = new Point(133, 123);
    Point p2 = new Point(149, 136);
    Point p3 = new Point(182, 136);
    Point p4 = new Point(206, 118);
    Point p5 = new Point(208, 87);
    Point p6 = new Point(187, 71);
    Point p7 = new Point(144, 78);
    Point p8 = new Point(124, 101);
    Point p9 = new Point(113, 128);
    Point p10 = new Point(112, 157);
    Point p11 = new Point(119, 188);
    Point p12 = new Point(134, 209);
    Point p13 = new Point(162, 228);
    Point p14 = new Point(194, 238);
    Point p15 = new Point(232, 240);
    Point p16 = new Point(263, 237);
    Point p17 = new Point(289, 224);
    Point p18 = new Point(315, 204);
    Point p19 = new Point(332, 174);
    Point p20 = new Point(339, 128);
    Point p21 = new Point(329, 95);
    Point p22 = new Point(304, 73);
    Point p23 = new Point(280, 69);
    Point p24 = new Point(254, 87);
    Point p25 = new Point(248, 116);
    Point p26 = new Point(259, 143);
    Point p27 = new Point(278, 153);
    Point p28 = new Point(241, 157);
    Point p29 = new Point(192, 160);
    Point p30 = new Point(150, 159);
    mPoints.add(p1);
    mPoints.add(p2);
    mPoints.add(p3);
    mPoints.add(p4);
    mPoints.add(p5);
    mPoints.add(p6);
    mPoints.add(p7);
    mPoints.add(p8);
    mPoints.add(p9);
    mPoints.add(p10);
    mPoints.add(p11);
    mPoints.add(p12);
    mPoints.add(p13);
    mPoints.add(p14);
    mPoints.add(p15);
    mPoints.add(p16);
    mPoints.add(p17);
    mPoints.add(p18);
    mPoints.add(p19);
    mPoints.add(p20);
    mPoints.add(p21);
    mPoints.add(p22);
    mPoints.add(p23);
    mPoints.add(p24);
    mPoints.add(p25);
    mPoints.add(p26);
    mPoints.add(p27);
    mPoints.add(p28);
    mPoints.add(p29);
    mPoints.add(p30);
}

public PaintView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    mCanvas = new Canvas();
    mPath = new Path();
    mPaint = new Paint();
    mPaint.setAntiAlias(true);
    mPaint.setDither(true);
    mPaint.setColor(Color.BLACK);
    mPaint.setStyle(Paint.Style.STROKE);
    mPaint.setStrokeJoin(Paint.Join.ROUND);
    mPaint.setStrokeCap(Paint.Cap.ROUND);
    mPaint.setStrokeWidth(12);
    mTouchTolerance = dp2px(TOUCH_TOLERANCE_DP);
}

@Override
protected void onSizeChanged(int width, int height, int oldWidth, int oldHeight) {
    super.onSizeChanged(width, height, oldWidth, oldHeight);
    clear();

}

@Override
protected void onDraw(Canvas canvas) {
    canvas.drawColor(BACKGROUND);
    canvas.drawBitmap(mBitmap, 0, 0, null);
    canvas.drawPath(mPath, mPaint);

    // TODO remove if you dont want points to be drawn
    for (Point point : mPoints) {
        canvas.drawPoint(point.x, point.y, mPaint);
    }
}

@Override
public boolean onTouchEvent(MotionEvent event) {
    float x = event.getX();
    float y = event.getY();

    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            touch_start(x, y);
            invalidate();
            break;
        case MotionEvent.ACTION_MOVE:
            touch_move(x, y);
            invalidate();
            break;
        case MotionEvent.ACTION_UP:
            touch_up(x, y);
            invalidate();
            break;
    }
    return true;
}

private void touch_start(float x, float y) {

    if (checkPoint(x, y, mLastPointIndex)) {
        mPath.reset();
        // user starts from given point so path can beis started
        isPathStarted = true;
    } else {
        // user starts move from point which doen's belongs to mPinst list
        isPathStarted = false;
    }

}

//ADDED WITH LAST EDIT
private void touch_move(float x, float y) {
    // draw line with finger move
    if (isPathStarted) {
        mPath.reset();
        Point p = mPoints.get(mLastPointIndex);
        mPath.moveTo(p.x, p.y);
        if (checkPoint(x, y, mLastPointIndex + 1)) {
            p = mPoints.get(mLastPointIndex + 1);
            mPath.lineTo(p.x, p.y);
            mCanvas.drawPath(mPath, mPaint);
            mPath.reset();
            ++mLastPointIndex;
        } else {
            mPath.lineTo(x, y);
        }
    }
}

/**
 * Draws line.
 */
private void touch_up(float x, float y) {
    mPath.reset();
    if (checkPoint(x, y, mLastPointIndex + 1) && isPathStarted) {
        // move finished at valid point so draw whole line

        // start point
        Point p = mPoints.get(mLastPointIndex);
        mPath.moveTo(p.x, p.y);
        // end point
        p = mPoints.get(mLastPointIndex + 1);
        mPath.lineTo(p.x, p.y);
        mCanvas.drawPath(mPath, mPaint);
        mPath.reset();
        // increment point index
        ++mLastPointIndex;
        isPathStarted = false;
    }

}

/**
 * Sets paint
 * 
 * @param paint
 */
public void setPaint(Paint paint) {
    this.mPaint = paint;
}

/**
 * Returns image as bitmap
 * 
 * @return
 */
public Bitmap getBitmap() {
    return mBitmap;
}

/**
 * Clears canvas
 */
public void clear() {
    mBitmap = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);
    mBitmap.eraseColor(BACKGROUND);
    mCanvas.setBitmap(mBitmap);
    invalidate();
}

/**
 * Checks if user touch point with some tolerance
 */
private boolean checkPoint(float x, float y, int pointIndex) {
    if (pointIndex == mPoints.size()) {
        // out of bounds
        return false;
    }
    Point point = mPoints.get(pointIndex);
    if (x > (point.x - mTouchTolerance) && x < (point.y + mTouchTolerance)) {
        if (y > (point.y - mTouchTolerance) && y < (point.y + mTouchTolerance)) {
            return true;
        }
    }
    return false;
}

public List<Point> getPoints() {
    return mPoints;
}

public void setPoints(List<Point> points) {
    this.mPoints = points;
}

private int dp2px(int dp) {
    Resources r = getContext().getResources();
    float px = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, r.getDisplayMetrics());
    return (int) px;
}
}

我是否还遗漏了什么？

2
https://dev59.com/q2gv5IYBdhLWcg3wFs2m - Nirav Ranpara
1
@sulemankhan：好的，我会给你演示。请等一会儿。 - Nirav Ranpara
@SulemanKhan：你得到了答案吗？ - Nirav Ranpara
@NiravRanpara 我已经知道如何做了。但是我的想法是想放置一些隐藏的点，并让用户触摸这些点来画出经过这些点的图像，就像在问题中给出的游戏链接中那样。在那里，这些点是可见的，但我希望它们除了第一个点以外都是不可见的。 - Suleman Khan
@NiravRanpara，我想知道如何在两个点之间画线，它必须从给定的点开始，并且只能结束于给定的点，有一个条件是如果那个点被触碰到，那么它们之间的线才会被画出。请帮帮我，我非常需要它。谢谢。 - Suleman Khan
显示剩余2条评论
2个回答
12

我做了类似的事情，但我不确定它是否正是您期望的。尝试这个PaintView的实现：

编辑： 添加touch_move()以沿手指移动绘制线条。

编辑2： 要使用一次移动绘制多条线，请将touch_move()方法更改为此方法：

private void touch_move(float x, float y) {
// draw line with finger move
if (isPathStarted) {
    mPath.reset();
    Point p = mPoints.get(mLastPointIndex);
    mPath.moveTo(p.x, p.y);
    if (checkPoint(x, y, mLastPointIndex + 1)) {
        p = mPoints.get(mLastPointIndex + 1);
        mPath.lineTo(p.x, p.y);
        mCanvas.drawPath(mPath, mPaint);
        mPath.reset();
        ++mLastPointIndex;
    } else {
        mPath.lineTo(x, y);
    }
}
}

_

public class PaintView extends View {

private Bitmap mBitmap;
private Canvas mCanvas;
private Path mPath;
private Paint mPaint;
private static final int TOUCH_TOLERANCE_DP = 24;
private static final int BACKGROUND = 0xFFDDDDDD;
private List<Point> mPoints = new ArrayList<Point>();
private int mLastPointIndex = 0;
private int mTouchTolerance;
private boolean isPathStarted = false;

public PaintView(Context context) {
    super(context);
    mCanvas = new Canvas();
    mPath = new Path();
    mPaint = new Paint();
    mPaint.setAntiAlias(true);
    mPaint.setDither(true);
    mPaint.setColor(Color.BLACK);
    mPaint.setStyle(Paint.Style.STROKE);
    mPaint.setStrokeJoin(Paint.Join.ROUND);
    mPaint.setStrokeCap(Paint.Cap.ROUND);
    mPaint.setStrokeWidth(12);
    mTouchTolerance = dp2px(TOUCH_TOLERANCE_DP);

    // TODO just test points
    Point p1 = new Point(20, 20);
    Point p2 = new Point(100, 100);
    Point p3 = new Point(200, 250);
    Point p4 = new Point(280, 400);
    Point p5 = new Point(350, 600);
    Point p6 = new Point(400, 500);
    mPoints.add(p1);
    mPoints.add(p2);
    mPoints.add(p3);
    mPoints.add(p4);
    mPoints.add(p5);
    mPoints.add(p6);
}

public PaintView(Context context, AttributeSet attrs) {
    super(context, attrs);
    mCanvas = new Canvas();
    mPath = new Path();
    mPaint = new Paint();
    mPaint.setAntiAlias(true);
    mPaint.setDither(true);
    mPaint.setColor(Color.BLACK);
    mPaint.setStyle(Paint.Style.STROKE);
    mPaint.setStrokeJoin(Paint.Join.ROUND);
    mPaint.setStrokeCap(Paint.Cap.ROUND);
    mPaint.setStrokeWidth(12);
    mTouchTolerance = dp2px(TOUCH_TOLERANCE_DP);

    // TODO just test points
    Point p1 = new Point(20, 20);
    Point p2 = new Point(100, 100);
    Point p3 = new Point(200, 250);
    Point p4 = new Point(280, 400);
    Point p5 = new Point(350, 600);
    Point p6 = new Point(400, 500);
    mPoints.add(p1);
    mPoints.add(p2);
    mPoints.add(p3);
    mPoints.add(p4);
    mPoints.add(p5);
    mPoints.add(p6);
}

public PaintView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    mCanvas = new Canvas();
    mPath = new Path();
    mPaint = new Paint();
    mPaint.setAntiAlias(true);
    mPaint.setDither(true);
    mPaint.setColor(Color.BLACK);
    mPaint.setStyle(Paint.Style.STROKE);
    mPaint.setStrokeJoin(Paint.Join.ROUND);
    mPaint.setStrokeCap(Paint.Cap.ROUND);
    mPaint.setStrokeWidth(12);
    mTouchTolerance = dp2px(TOUCH_TOLERANCE_DP);
}

@Override
protected void onSizeChanged(int width, int height, int oldWidth, int oldHeight) {
    super.onSizeChanged(width, height, oldWidth, oldHeight);
    clear();

}

@Override
protected void onDraw(Canvas canvas) {
    canvas.drawColor(BACKGROUND);
    canvas.drawBitmap(mBitmap, 0, 0, null);
    canvas.drawPath(mPath, mPaint);

    // TODO remove if you dont want points to be drawn
    for (Point point : mPoints) {
        canvas.drawPoint(point.x, point.y, mPaint);
    }
}

@Override
public boolean onTouchEvent(MotionEvent event) {
    float x = event.getX();
    float y = event.getY();

    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            touch_start(x, y);
            invalidate();
            break;
        case MotionEvent.ACTION_MOVE:
            touch_move(x, y);
            invalidate();
            break;
        case MotionEvent.ACTION_UP:
            touch_up(x, y);
            invalidate();
            break;
    }
    return true;
}

private void touch_start(float x, float y) {

    if (checkPoint(x, y, mLastPointIndex)) {
        mPath.reset();
        // user starts from given point so path can beis started
        isPathStarted = true;
    } else {
        // user starts move from point which doen's belongs to mPinst list
        isPathStarted = false;
    }

}

//ADDED WITH LAST EDIT
private void touch_move(float x, float y) {
    // draw line with finger move
    if (isPathStarted) {
        mPath.reset();
        Point p = mPoints.get(mLastPointIndex);
        mPath.moveTo(p.x, p.y);
        mPath.lineTo(x, y);
    }
}

/**
 * Draws line.
 */
private void touch_up(float x, float y) {
    mPath.reset();
    if (checkPoint(x, y, mLastPointIndex + 1) && isPathStarted) {
        // move finished at valid point so draw whole line

        // start point
        Point p = mPoints.get(mLastPointIndex);
        mPath.moveTo(p.x, p.y);
        // end point
        p = mPoints.get(mLastPointIndex + 1);
        mPath.lineTo(p.x, p.y);
        mCanvas.drawPath(mPath, mPaint);
        mPath.reset();
        // increment point index
        ++mLastPointIndex;
        isPathStarted = false;
    }

}

/**
 * Sets paint
 * 
 * @param paint
 */
public void setPaint(Paint paint) {
    this.mPaint = paint;
}

/**
 * Returns image as bitmap
 * 
 * @return
 */
public Bitmap getBitmap() {
    return mBitmap;
}

/**
 * Clears canvas
 */
public void clear() {
    mBitmap = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);
    mBitmap.eraseColor(BACKGROUND);
    mCanvas.setBitmap(mBitmap);
    invalidate();
}

/**
 * Checks if user touch point with some tolerance
 */
private boolean checkPoint(float x, float y, int pointIndex) {
    if (pointIndex == mPoints.size()) {
        // out of bounds
        return false;
    }
    Point point = mPoints.get(pointIndex);
    //EDIT changed point.y to poin.x in the first if statement
    if (x > (point.x - mTouchTolerance) && x < (point.x + mTouchTolerance)) {
        if (y > (point.y - mTouchTolerance) && y < (point.y + mTouchTolerance)) {
            return true;
        }
    }
    return false;
}

public List<Point> getPoints() {
    return mPoints;
}

public void setPoints(List<Point> points) {
    this.mPoints = points;
}

private int dp2px(int dp) {
    Resources r = getContext().getResources();
    float px = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, r.getDisplayMetrics());
    return (int) px;
}

我从XML中使用它，但你也可以通过代码创建，简单的XML：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

    <com.example.lecho.PaintView
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

</RelativeLayout>
是的，这几乎是我所需要的，但我们不能使用相同的功能沿着手指绘制吗？在这里，线条是在 action_up 之后绘制的，我们不能沿着手指做到这一点吗？ - Suleman Khan
1
在 checkPoint() 方法中，将第 if (x > (point.x - mTouchTolerance) && x < (point.y + mTouchTolerance)) 行中的 point.y 改为 point.x，回答已编辑 :) - Leszek
抱歉打扰您了。但只有一个最后的疑问。如何根据屏幕大小更改这些点？ - Suleman Khan
@leszek，是否可以使用手指触摸路径而不是直线在两个点之间绘制线条？ - Parul
现在是2022年，你的回答仍然对我有所帮助。 处理画布上的直线的好方法。 - Ammar
显示剩余6条评论
0

这里我放置了在画布上绘制对象的代码。你可以绘制线条、圆形等等。

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello" />

</LinearLayout>

SampleCanvasActivity.java

public class SampleCanvasActivity extends Activity implements OnTouchListener {

    DrawPanel dp;
    private ArrayList<Path> pointsToDraw = new ArrayList<Path>();
    private Paint mPaint;
    Path path;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.main);
        dp = new DrawPanel(this); 
        dp.setOnTouchListener(this);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
        mPaint = new Paint();
        mPaint.setDither(true);
        mPaint.setColor(Color.WHITE);
        mPaint.setStyle(Paint.Style.STROKE);
        mPaint.setStrokeJoin(Paint.Join.ROUND);
        mPaint.setStrokeCap(Paint.Cap.ROUND);

        mPaint.setStrokeWidth(3);
        FrameLayout fl = new FrameLayout(this);  
        fl.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));  
        fl.addView(dp);  
        setContentView(fl);  
    }


    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        dp.pause();
    }
    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        dp.resume();
    }

    public boolean onTouch(View v, MotionEvent me) {
        // TODO Auto-generated method stub
                synchronized(pointsToDraw)
                {
        if(me.getAction() == MotionEvent.ACTION_DOWN){
            path = new Path();
            path.moveTo(me.getX(), me.getY());
            Log.e("Location", String.valueOf("x : "+ me.getX()+ "y : " +me.getY()));
            //path.lineTo(me.getX(), me.getY());
            pointsToDraw.add(path);
        }else if(me.getAction() == MotionEvent.ACTION_MOVE){
            path.lineTo(me.getX(), me.getY());
        }else if(me.getAction() == MotionEvent.ACTION_UP){
            //path.lineTo(me.getX(), me.getY());
        }
        }       
        return true;
    }


    public class DrawPanel extends SurfaceView implements Runnable{

        Thread t = null;
        SurfaceHolder holder;
        boolean isItOk = false ;

        public DrawPanel(Context context) {
            super(context);
            // TODO Auto-generated constructor stub
            holder = getHolder();
        }

        public void run() {
            // TODO Auto-generated method stub
            while( isItOk == true){

                if(!holder.getSurface().isValid()){
                    continue;
                }

                Canvas c = holder.lockCanvas();

                c.drawARGB(255, 0, 0, 0);
                onDraw(c);
                holder.unlockCanvasAndPost(c);
            }
        }

        @Override
        protected void onDraw(Canvas canvas) {
            // TODO Auto-generated method stub
            super.onDraw(canvas);
                        synchronized(pointsToDraw)
                        {
            for (Path path : pointsToDraw) {
                canvas.drawPath(path, mPaint);
            }
                        }
        }

        public void pause(){
            isItOk = false;
            while(true){
                try{
                    t.join();
                }catch(InterruptedException e){
                    e.printStackTrace();
                }
                break;
            }
            t = null;
        }

        public void resume(){
            isItOk = true;  
            t = new Thread(this);
            t.start();

        }
    }
}
我已经知道如何做了。但是我想做的是，我想放一些看不见的点，让用户触摸这些点来画出这些点，就像问题中给出的游戏链接那样。那里的点是可见的，但是在这里，除了第一个点外，我希望它们都是看不见的。 - Suleman Khan
我没有看到绘制线条、圆形等图形的方法。目前我只能进行自由绘制。 - Dyno Cris
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