我实际上可以使用FingerPaint in API Demos
样本中提供的Android SDK
在我的应用中用手指绘制线条。但是如何仅用手指沿着屏幕上的点绘制这些线条。我想要这样的应用程序:https://play.google.com/store/apps/details?id=zok.android.dots
我只想用手指在第1点和第2点之间画线。必须仅在触摸点2时绘制1到2之间的线,否则不应绘制。同样,再次从第2点到第3点,依此类推。
请帮我一个代码。
提前致谢
P.S。在回答之前,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;
}
}
我还缺少什么吗?
答案 0 :(得分:8)
我做了类似的事情,但我不确定它是否正是你所期待的。试试PaintView
:
编辑:
将touch_move()
添加到手指移动的绘制线上。
EDIT2:
要通过一次移动绘制多行,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;
}
}
我在xml中使用它,但您也可以从代码中创建它,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>
答案 1 :(得分:0)
这里我将绘图对象的代码放在画布上。你可以画线,圆等。
<强> main.xml中强>
<?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>
<强> SampleCanvasActivity.java 强>
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();
}
}
}