问题
I am trying two draw digital signature using Bezier as show in above image.when i touch and try to draw line then the result is dot line but not getting continuous line. Simple signature done by using simple signature but I want to create more a smooth curve using Bezier with touch pressure. tried with this link
SignatureViewDemo.java
public class SignatureViewDemo extends View {
private int color = Color.BLACK;
private Bitmap m_Bitmap;
private final Paint m_BorderPaint;
private Canvas m_Canvas;
private Point m_CropBotRight;
private Point m_CropTopLeft;
private float m_CurrentX;
private float m_CurrentY;
private final float m_DesiredDash;
private float m_LastWidth = 6.5F;
private Paint m_PenPaint;
private int m_PointIndex = 0;
private ArrayList<Point> m_Points = new ArrayList<Point>();
private final float m_StrokeWidth;
boolean m_Empty;
public SignatureViewDemo(Context paramContext) {
this(paramContext, null);
}
public SignatureViewDemo(Context paramContext,
AttributeSet paramAttributeSet) {
this(paramContext, paramAttributeSet, 0);
}
public SignatureViewDemo(Context paramContext,
AttributeSet paramAttributeSet, int paramInt) {
super(paramContext, paramAttributeSet, paramInt);
setFocusable(true);
this.m_PenPaint = new Paint();
this.m_PenPaint.setAntiAlias(true);
this.m_PenPaint.setColor(Color.BLACK);
this.m_PenPaint.setStrokeWidth(5.0F);
this.m_PenPaint.setStrokeJoin(Paint.Join.ROUND);
this.m_PenPaint.setStrokeCap(Paint.Cap.ROUND);
this.m_CurrentY = (0.0F / 0.0F);
this.m_CurrentX = (0.0F / 0.0F);
this.m_StrokeWidth = 5.0F;
this.m_DesiredDash = 10.0F;
this.m_BorderPaint = new Paint();
this.m_BorderPaint.setColor(Color.BLACK);
this.m_BorderPaint.setStyle(Paint.Style.STROKE);
this.m_BorderPaint.setStrokeWidth(this.m_StrokeWidth);
}
public void addBezier(Bezier paramBezier, float paramFloat1,
float paramFloat2) {
if (this.m_Bitmap == null) {
this.m_Bitmap = Bitmap.createBitmap(getWidth(), getHeight(),
Bitmap.Config.ARGB_8888);
this.m_Canvas = new Canvas(this.m_Bitmap);
}
paramBezier.draw(this.m_Canvas, this.m_PenPaint, paramFloat1,
paramFloat2);
}
public void addPoint(Point paramPoint) {
if ((paramPoint.getX() < this.m_CropTopLeft.getX())
&& (paramPoint.getX() >= 0.0F))
this.m_CropTopLeft.setX(paramPoint.getX());
if ((paramPoint.getY() < this.m_CropTopLeft.getY())
&& (paramPoint.getY() >= 0.0F))
this.m_CropTopLeft.setY(paramPoint.getY());
if ((paramPoint.getX() > this.m_CropBotRight.getX())
&& (paramPoint.getX() <= this.m_Canvas.getWidth()))
this.m_CropBotRight.setX(paramPoint.getX());
if ((paramPoint.getY() > this.m_CropBotRight.getY())
&& (paramPoint.getY() <= this.m_Canvas.getHeight()))
this.m_CropBotRight.setY(paramPoint.getY());
this.m_Points.add(paramPoint);
drawPoints();
}
// public void clear() {
// if (this.m_Canvas == null)
// this.m_Canvas.drawColor(0, PorterDuff.Mode.CLEAR);
// invalidate();
// // return;
// }
public void clear() {
if (this.m_Canvas == null)
return;
while (m_Empty) {
m_Canvas.drawColor(0, PorterDuff.Mode.CLEAR);
m_Empty = true;
invalidate();
return;
}
}
public void drawBitmap(Bitmap paramBitmap) {
clear();
if ((paramBitmap != null) && (this.m_Canvas != null)
&& (this.m_Canvas.getWidth() != 0)
&& (this.m_Canvas.getHeight() != 0)) {
Matrix localMatrix = new Matrix();
localMatrix.setRectToRect(
new RectF(0.0F, 0.0F, paramBitmap.getWidth(), paramBitmap
.getHeight()),
new RectF(0.0F, 0.0F, this.m_Canvas.getWidth(),
this.m_Canvas.getHeight()),
Matrix.ScaleToFit.CENTER);
this.m_Canvas.drawBitmap(paramBitmap, localMatrix, null);
m_Empty = false;
}
invalidate();
}
public void drawPoints() {
if ((m_Points.size() >= 4)
&& (4 + this.m_PointIndex <= this.m_Points.size())) {
Point localPoint1 = (Point) this.m_Points.get(this.m_PointIndex);
Point localPoint2 = (Point) this.m_Points
.get(1 + this.m_PointIndex);
Point localPoint3 = (Point) this.m_Points
.get(2 + this.m_PointIndex);
Point localPoint4 = (Point) this.m_Points
.get(3 + this.m_PointIndex);
Bezier localBezier = new Bezier(localPoint1, localPoint2,
localPoint3, localPoint4);
localBezier.setColor(Color.GREEN);
float f = strokeWidth(8.0F / localPoint4.velocityFrom(localPoint1));
addBezier(localBezier, this.m_LastWidth, f);
invalidate();
this.m_LastWidth = f;
this.m_PointIndex = (3 + this.m_PointIndex);
m_Empty = false;
}
}
public boolean isEmpty() {
return m_Empty;
}
public Bitmap getBitmap() {
return this.m_Bitmap;
}
public int getColor() {
return this.color;
}
protected void onDraw(Canvas paramCanvas) {
if (this.m_Bitmap != null)
paramCanvas.drawBitmap(this.m_Bitmap, 0.0F, 0.0F, null);
}
protected void onMeasure(int paramInt1, int paramInt2) {
int i = View.MeasureSpec.getSize(paramInt1);
int j = View.MeasureSpec.getSize(paramInt2);
this.m_CropTopLeft = new Point(i, j);
this.m_CropBotRight = new Point(0.0F, 0.0F);
setMeasuredDimension(i, j);
}
protected void onSizeChanged(int paramInt1, int paramInt2, int paramInt3,
int paramInt4) {
Bitmap localBitmap = Bitmap.createBitmap(paramInt1, paramInt2,
Bitmap.Config.ARGB_8888);
this.m_Canvas = new Canvas(localBitmap);
float f1 = 2.0F * (this.m_Canvas.getWidth() + this.m_Canvas.getHeight() - 2.0F * this.m_StrokeWidth);
float f2 = f1
* this.m_DesiredDash
/ (Math.round(f1 / (4.0F * this.m_DesiredDash)) * (4.0F * this.m_DesiredDash));
Paint localPaint = this.m_BorderPaint;
float[] arrayOfFloat = new float[2];
arrayOfFloat[0] = f2;
arrayOfFloat[1] = f2;
localPaint.setPathEffect(new DashPathEffect(arrayOfFloat, f2 / 2.0F));
clear();
if (this.m_Bitmap != null) {
Rect localRect = new Rect(0, 0, this.m_Canvas.getWidth(),
this.m_Canvas.getHeight());
this.m_Canvas.drawBitmap(this.m_Bitmap, null, localRect, null);
m_Empty = false;
}
this.m_Bitmap = localBitmap;
}
public boolean onTouchEvent(MotionEvent paramMotionEvent) {
int i = 0xFF & paramMotionEvent.getAction();
if (i == 0) {
this.m_CurrentX = paramMotionEvent.getX();
this.m_CurrentY = paramMotionEvent.getY();
addPoint(new Point(this.m_CurrentX, this.m_CurrentY,
paramMotionEvent.getEventTime()));
getParent().requestDisallowInterceptTouchEvent(true);
}
// while (m_Empty) {
if ((i == 1) || (i == 3)) {
this.m_CurrentY = (0.0F / 0.0F);
this.m_CurrentX = (0.0F / 0.0F);
this.m_Points.clear();
this.m_PointIndex = 0;
getParent().requestDisallowInterceptTouchEvent(false);
}
// if ((this.m_Points.size() < 4) || (4 + this.m_PointIndex >
// this.m_Points.size()))
// while (1 + this.m_PointIndex <= this.m_Points.size())
drawPoints();
if ((i == 2) || (i == 1)) {
for (int j = 0; j < paramMotionEvent.getHistorySize(); j++)
addPoint(new Point(paramMotionEvent.getHistoricalX(j),
paramMotionEvent.getHistoricalY(j),
paramMotionEvent.getHistoricalEventTime(j)));
addPoint(new Point(paramMotionEvent.getX(),
paramMotionEvent.getY(), paramMotionEvent.getEventTime()));
}
// }
return true;
}
public void setColor(int paramInt) {
this.color = Color.BLACK;
}
public Point getCropBotRight() {
return this.m_CropBotRight;
}
public Point getCropTopLeft() {
return this.m_CropTopLeft;
}
// public float strokeWidth(float paramFloat) {
// if (paramFloat > 11.0F)
// paramFloat = 10.0F;
// if (paramFloat < 5.0F)
// paramFloat = 6.0F;
// return paramFloat;
// }
public float strokeWidth(float paramFloat) {
if (paramFloat > 11.0F)
paramFloat = 10.0F;
while (m_Empty) {
if (paramFloat < 5.0F)
paramFloat = 6.0F;
return paramFloat;
}
return paramFloat;
}
}
Point.java
private long time;
private float x;
private float y;
public Point(float paramFloat1, float paramFloat2) {
this.x = paramFloat1;
this.y = paramFloat2;
}
public Point(float paramFloat1, float paramFloat2, long paramLong) {
this.x = paramFloat1;
this.y = paramFloat2;
this.time = paramLong;
}
protected float distanceTo(Point paramPoint) {
float f1 = this.x - paramPoint.getX();
float f2 = this.y - paramPoint.getY();
return FloatMath.sqrt(f1 * f1 + f2 * f2);
}
public long getTime() {
return this.time;
}
public float getX() {
return this.x;
}
public float getY() {
return this.y;
}
public void setX(float paramFloat) {
this.x = paramFloat;
}
public void setY(float paramFloat) {
this.y = paramFloat;
}
public float velocityFrom(Point paramPoint) {
return distanceTo(paramPoint) / (this.time - paramPoint.time);
}
}
Bezier.java
public class Bezier {
private Point controlPointOne;
private Point controlPointTwo;
private int drawSteps;
private Point endPoint;
private int mColor;
private Point startPoint;
public Bezier() {
}
public Bezier(Point paramPoint1, Point paramPoint2, Point paramPoint3,
Point paramPoint4) {
this.startPoint = paramPoint1;
this.controlPointOne = paramPoint2;
this.controlPointTwo = paramPoint3;
this.endPoint = paramPoint4;
this.drawSteps = ((int) (paramPoint1.distanceTo(paramPoint2)
+ paramPoint2.distanceTo(paramPoint3) + paramPoint3
.distanceTo(paramPoint4)));
}
public void draw(Canvas paramCanvas, Paint paramPaint, float paramFloat1,
float paramFloat2) {
float f1 = paramFloat2 - paramFloat1;
for (int i = 0; i < this.drawSteps; i++) {
float f2 = i / this.drawSteps;
float f3 = f2 * f2;
float f4 = f3 * f2;
float f5 = 1.0F - f2;
float f6 = f5 * f5;
float f7 = f6 * f5;
float f8 = f7 * this.startPoint.getX() + f2 * (3.0F * f6)
* this.controlPointOne.getX() + f3 * (3.0F * f5)
* this.controlPointTwo.getX() + f4 * this.endPoint.getX();
float f9 = f7 * this.startPoint.getY() + f2 * (3.0F * f6)
* this.controlPointOne.getY() + f3 * (3.0F * f5)
* this.controlPointTwo.getY() + f4 * this.endPoint.getY();
paramPaint.setColor(getColor());
paramPaint.setStrokeWidth(paramFloat1 + f4 * f1);
paramCanvas.drawPoint(f8, f9, paramPaint);
}
}
public int getColor() {
return this.mColor;
}
public Point getControlPointOne() {
return this.controlPointOne;
}
public Point getControlPointTwo() {
return this.controlPointTwo;
}
public int getDrawSteps() {
return this.drawSteps;
}
public Point getEndPoint() {
return this.endPoint;
}
public Point getStartPoint() {
return this.startPoint;
}
public void setColor(int paramInt) {
this.mColor = Color.BLACK;
}
public void setControlPointOne(Point paramPoint) {
this.controlPointOne = paramPoint;
}
public void setControlPointTwo(Point paramPoint) {
this.controlPointTwo = paramPoint;
}
public void setDrawSteps(int paramInt) {
this.drawSteps = paramInt;
}
public void setEndPoint(Point paramPoint) {
this.endPoint = paramPoint;
}
public void setStartPoint(Point paramPoint) {
this.startPoint = paramPoint;
}
}
回答1:
Change draw method in Bezier class to:
public void draw(Canvas canvas, Paint paint, float startWidth, float endWidth) {
float originalWidth = paint.getStrokeWidth();
float widthDelta = endWidth - startWidth;
for (int i = 0; i < drawSteps; i++) {
float t = ((float) i) / drawSteps;
float tt = t * t;
float ttt = tt * t;
float u = 1 - t;
float uu = u * u;
float uuu = uu * u;
float x = uuu * startPoint.x;
x += 3 * uu * t * getControlPointOne().x;
x += 3 * u * tt * getControlPointTwo().x;
x += ttt * endPoint.x;
float y = uuu * startPoint.y;
y += 3 * uu * t * getControlPointOne().y;
y += 3 * u * tt * getControlPointTwo().y;
y += ttt * endPoint.y;
paint.setStrokeWidth(startWidth + ttt * widthDelta);
canvas.drawPoint(x, y, paint);
}
paint.setStrokeWidth(originalWidth);
}
回答2:
You need to see how many points are drawn in Bezier class and add them up.
From your code: You are collecting 4 points and draw a Bezier curve over them. This means that the algorithm - by design - will miss half of the sampled points.
Other options: 1. Create your own Bezier curve or lower order (say - order 3) - and then you'll miss only 1/3 of the points. This kinda renders the issue useless, as you want to conserve less data than sampled. 2. Create a high order Bezier curve that can approximate the whole signature.
You can, however, try to figure out what points you would like to select in order to get a Bezier curve which is closer to the signature : select the top of the letter 'l' as an end point of one Bezier curve and the start of another will yield better results.
回答3:
You can use simple
code
public class MySignatureView extends View
{
private Path mPath;
private Paint mPaint;
private Bitmap mBitmap;
private Canvas mCanvas;
private int bgColor;
private float curX, curY;
private boolean isDragged = false;
private static final int TOUCH_TOLERANCE = 4;
private static final int STROKE_WIDTH = 2;
public MySignatureView(Context context) {
super(context);
init();
}
public MySignatureView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public MySignatureView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() {
setFocusable(true);
bgColor = Color.WHITE;
mPath = new Path();
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setColor(bgColor ^ 0x00FFFFFF);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeWidth(STROKE_WIDTH);
}
public void setSigColor(int color) {
mPaint.setColor(color);
}
public void setSigColor(int a, int r, int g, int b) {
mPaint.setARGB(a, r, g, b);
}
public void clearSig() {
if (mCanvas != null) {
mCanvas.drawColor(bgColor);
mCanvas.drawPaint(mPaint);
mPath.reset();
invalidate();
}
}
public Bitmap getImage() {
return this.mBitmap;
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
int bitW = mBitmap != null ? mBitmap.getWidth() : 0;
int bitH = mBitmap != null ? mBitmap.getWidth() : 0;
if (bitW >= w && bitH >= h) {
return;
}
if (bitW < w)
bitW = w;
if (bitH < h)
bitH = h;
Bitmap newBitmap = Bitmap.createBitmap(bitW, bitH,
Bitmap.Config.ARGB_8888);
Canvas newCanvas = new Canvas();
newCanvas.setBitmap(newBitmap);
if (mBitmap != null) {
newCanvas.drawBitmap(mBitmap, 0, 0, null);
}
mBitmap = newBitmap;
mCanvas = newCanvas;
}
@Override
protected void onDraw(Canvas canvas) {
canvas.drawBitmap(mBitmap, 0, 0, mPaint);
canvas.drawPath(mPath, mPaint);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
float x = event.getX();
float y = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
touchDown(x, y);
break;
case MotionEvent.ACTION_MOVE:
touchMove(x, y);
break;
case MotionEvent.ACTION_UP:
touchUp();
break;
}
invalidate();
return true;
}
private void touchDown(float x, float y) {
mPath.reset();
mPath.moveTo(x, y);
curX = x;
curY = y;
isDragged = false;
}
private void touchMove(float x, float y) {
float dx = Math.abs(x - curX);
float dy = Math.abs(y - curY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
mPath.quadTo(curX, curY, (x + curX) / 2, (y + curY) / 2);
curX = x;
curY = y;
isDragged = true;
}
}
private void touchUp() {
if (isDragged) {
mPath.lineTo(curX, curY);
} else {
mPath.lineTo(curX+2, curY+2);
}
mCanvas.drawPath(mPath, mPaint);
mPath.reset();
}
}
回答4:
You can use this,I have also attached the xml at the bottom:
import java.io.File;
import java.io.FileOutputStream;
import java.util.Calendar;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.ContextWrapper;
import android.content.DialogInterface;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.RectF;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore.Images;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup.LayoutParams;
import android.view.Window;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.Toast;
public class SignatureCapture extends Activity {
public LinearLayout mContent;
public signature mSignature;
public Button mClear, mGetSign, mCancel;
public static String tempDir;
public int count = 1;
public String current = null;
public static Bitmap mBitmap;
public View mView;
public File mypath;
private String uniqueId;
private EditText yourName;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.signature);
// tempDir = Environment.getExternalStorageDirectory() + "/" +
// getResources().getString(R.string.external_dir) + "/";
ContextWrapper cw = new ContextWrapper(getApplicationContext());
// File directory =
// cw.getDir(getResources().getString(R.string.external_dir),
// Context.MODE_PRIVATE);
File directory = new File(Environment.getExternalStorageDirectory()
+ "/GLP_Images");
if (!directory.exists())
directory.mkdir(); // directory is created;
// prepareDirectory();
uniqueId = getTodaysDate() + "_" + getCurrentTime();
current = uniqueId + ".png";
mypath = new File(directory, current);
mContent = (LinearLayout) findViewById(R.id.linearLayout);
mSignature = new signature(this, null);
mSignature.setBackgroundColor(Color.WHITE);
mContent.addView(mSignature, LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT);
mClear = (Button) findViewById(R.id.clear);
mGetSign = (Button) findViewById(R.id.getsign);
mGetSign.setEnabled(false);
mCancel = (Button) findViewById(R.id.cancel);
mView = mContent;
// yourName = (EditText) findViewById(R.id.yourName);
mClear.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Log.v("log_tag", "Panel Cleared");
mSignature.clear();
mGetSign.setEnabled(false);
}
});
mGetSign.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Log.v("log_tag", "Panel Saved");
// boolean error = captureSignature();
// if(error){
mView.setDrawingCacheEnabled(true);
mSignature.save(mView);
// Bundle b = new Bundle();
// b.putString("status", "done");
/*
* Intent intent = new
* Intent(SignatureCapture.this,SigntuareCaptureActivity.class);
* // intent.putExtra("imagePath",mypath);
* startActivity(intent); //intent.putExtra("status", "done");
* //setResult(RESULT_OK,intent); finish(); // }
*/
AlertDialog.Builder dialog = new AlertDialog.Builder(
SignatureCapture.this);
dialog.setMessage("Details saved");
dialog.setPositiveButton("OK",
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog,
int which) {
dialog.dismiss();
}
});
dialog.show();
}
});
mCancel.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Log.v("log_tag", "Panel Canceled");
Bundle b = new Bundle();
b.putString("status", "cancel");
Intent intent = new Intent();
intent.putExtras(b);
setResult(RESULT_OK, intent);
finish();
}
});
}
@Override
protected void onDestroy() {
Log.w("GetSignature", "onDestory");
super.onDestroy();
}
// private boolean captureSignature()
// {
//
// boolean error = false;
// String errorMessage = "";
//
//
// if(yourName.getText().toString().equalsIgnoreCase(""))
// {
// errorMessage = errorMessage + "Please enter your Name\n";
// error = true;
// }
//
// if(error)
// {
// Toast toast = Toast.makeText(this, errorMessage, Toast.LENGTH_SHORT);
// toast.setGravity(Gravity.TOP, 105, 50);
// toast.show();
// }
//
// return error;
// }
private String getTodaysDate() {
final Calendar c = Calendar.getInstance();
int todaysDate = (c.get(Calendar.YEAR) * 10000)
+ ((c.get(Calendar.MONTH) + 1) * 100)
+ (c.get(Calendar.DAY_OF_MONTH));
Log.w("DATE:", String.valueOf(todaysDate));
return (String.valueOf(todaysDate));
}
private String getCurrentTime() {
final Calendar c = Calendar.getInstance();
int currentTime = (c.get(Calendar.HOUR_OF_DAY) * 10000)
+ (c.get(Calendar.MINUTE) * 100) + (c.get(Calendar.SECOND));
Log.w("TIME:", String.valueOf(currentTime));
return (String.valueOf(currentTime));
}
private boolean prepareDirectory() {
try {
if (makedirs()) {
return true;
} else {
return false;
}
} catch (Exception e) {
e.printStackTrace();
Toast.makeText(
this,
"Could not initiate File System.. Is Sdcard mounted properly?",
1000).show();
return false;
}
}
private boolean makedirs() {
File tempdir = new File(tempDir);
if (!tempdir.exists())
tempdir.mkdirs();
if (tempdir.isDirectory()) {
File[] files = tempdir.listFiles();
for (File file : files) {
if (!file.delete()) {
System.out.println("Failed to delete " + file);
}
}
}
return (tempdir.isDirectory());
}
public class signature extends View {
private static final float STROKE_WIDTH = 5f;
private static final float HALF_STROKE_WIDTH = STROKE_WIDTH / 2;
private Paint paint = new Paint();
private Path path = new Path();
private float lastTouchX;
private float lastTouchY;
private final RectF dirtyRect = new RectF();
public signature(Context context, AttributeSet attrs) {
super(context, attrs);
paint.setAntiAlias(true);
paint.setColor(Color.BLACK);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeWidth(STROKE_WIDTH);
}
public void save(View v) {
Log.v("log_tag", "Width: " + v.getWidth());
Log.v("log_tag", "Height: " + v.getHeight());
if (mBitmap == null) {
mBitmap = Bitmap.createBitmap(mContent.getWidth(),
mContent.getHeight(), Bitmap.Config.RGB_565);
}
Canvas canvas = new Canvas(mBitmap);
try {
FileOutputStream mFileOutStream = new FileOutputStream(mypath);
v.draw(canvas);
mBitmap.compress(Bitmap.CompressFormat.PNG, 90, mFileOutStream);
mFileOutStream.flush();
mFileOutStream.close();
String url = Images.Media.insertImage(getContentResolver(),
mBitmap, "title", null);
// Log.v("log_tag","url: " + url);
// //In case you want to delete the file
// boolean deleted = mypath.delete();
// Log.v("log_tag","deleted: " + mypath.toString() + deleted);
// //If you want to convert the image to string use base64
// converter
} catch (Exception e) {
Log.v("log_tag", e.toString());
}
}
public void clear() {
path.reset();
invalidate();
}
@Override
protected void onDraw(Canvas canvas) {
canvas.drawPath(path, paint);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
float eventX = event.getX();
float eventY = event.getY();
mGetSign.setEnabled(true);
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
path.moveTo(eventX, eventY);
lastTouchX = eventX;
lastTouchY = eventY;
return true;
case MotionEvent.ACTION_MOVE:
case MotionEvent.ACTION_UP:
resetDirtyRect(eventX, eventY);
int historySize = event.getHistorySize();
for (int i = 0; i < historySize; i++) {
float historicalX = event.getHistoricalX(i);
float historicalY = event.getHistoricalY(i);
expandDirtyRect(historicalX, historicalY);
path.lineTo(historicalX, historicalY);
}
path.lineTo(eventX, eventY);
break;
default:
debug("Ignored touch event: " + event.toString());
return false;
}
invalidate((int) (dirtyRect.left - HALF_STROKE_WIDTH),
(int) (dirtyRect.top - HALF_STROKE_WIDTH),
(int) (dirtyRect.right + HALF_STROKE_WIDTH),
(int) (dirtyRect.bottom + HALF_STROKE_WIDTH));
lastTouchX = eventX;
lastTouchY = eventY;
return true;
}
private void debug(String string) {
}
private void expandDirtyRect(float historicalX, float historicalY) {
if (historicalX < dirtyRect.left) {
dirtyRect.left = historicalX;
} else if (historicalX > dirtyRect.right) {
dirtyRect.right = historicalX;
}
if (historicalY < dirtyRect.top) {
dirtyRect.top = historicalY;
} else if (historicalY > dirtyRect.bottom) {
dirtyRect.bottom = historicalY;
}
}
private void resetDirtyRect(float eventX, float eventY) {
dirtyRect.left = Math.min(lastTouchX, eventX);
dirtyRect.right = Math.max(lastTouchX, eventX);
dirtyRect.top = Math.min(lastTouchY, eventY);
dirtyRect.bottom = Math.max(lastTouchY, eventY);
}
}
}
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/linearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/header_bg"
android:gravity="center"
android:text="Signature"
android:textColor="@android:color/white"
android:textSize="20dp"
android:textStyle="bold" />
<LinearLayout
android:id="@+id/linearLayout"
android:layout_width="match_parent"
android:layout_weight="1"
android:layout_height="wrap_content"
android:orientation="vertical" />
<LinearLayout
android:id="@+id/linearLayout2"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<Button
android:id="@+id/cancel"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight=".30"
android:text="Cancel"
android:visibility="gone" />
<Button
android:id="@+id/clear"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Clear" />
<Button
android:id="@+id/getsign"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Save" />
</LinearLayout>
</LinearLayout>
来源：https://stackoverflow.com/questions/16455896/android-digital-signature-using-bezier