Drawing on canvas not working - android

I have the following xml setup:
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/content"
android:orientation="vertical">
</LinearLayout>
<ListView
android:id="#+id/navList"
android:layout_width="250dp"
android:layout_height="match_parent"
android:layout_gravity="left|start"
android:background="#cccccc"/>
</android.support.v4.widget.DrawerLayout>
I now would like to draw a canvas in that linear layout, therefore I do that:
Radar radar = new Radar(this, this.width);
content.addView(radar);
and here is the radar class:
private int width;
public Radar(Context context, int width){
super(context);
this.width = width;
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
Paint circlePaint = new Paint();
circlePaint.setColor(0xFF00FF00);
circlePaint.setStyle(Paint.Style.FILL);
Rect rect = new Rect();
rect.set(0, 0, canvas.getWidth(), canvas.getHeight() / 2);
canvas.drawRect(rect, circlePaint);
//canvas.drawCircle(0, 0, this.width, circlePaint);
}
The problem I encounter is that the canvas doesn't show up
How can I fix that?

I found the answer by adding setWillNotDraw(false);

It worked below code for me. you can also try similarly.
1) Add layout
<com.example.canvas.DrawingArea
android:id="#+id/drawing"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_marginBottom="3dp"
android:layout_weight="1"
android:background="#FFFFFFFF" />
2) Code
public class DrawingArea extends View {
private Path drawPath;
private Paint drawPaint, canvasPaint;
private int paintColor = 0xFF660000;
private Canvas drawCanvas;
private Bitmap canvasBitmap;
private boolean erase = false;
public DrawingArea(Context context) {
super(context);
setupDrawing();
}
public DrawingArea(Context context, AttributeSet attrs) {
super(context, attrs);
setupDrawing();
}
public void setupDrawing() {
drawPath = new Path();
drawPaint = new Paint();
drawPaint.setAntiAlias(true);
drawPaint.setStrokeWidth(20);
drawPaint.setStyle(Paint.Style.STROKE);
drawPaint.setStrokeJoin(Paint.Join.ROUND);
drawPaint.setStrokeCap(Paint.Cap.ROUND);
canvasPaint = new Paint(Paint.DITHER_FLAG);
}
public void setColor(String newColor) {
invalidate();
paintColor = Color.parseColor(newColor);
drawPaint.setColor(paintColor);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawBitmap(canvasBitmap, 0, 0, canvasPaint);
canvas.drawPath(drawPath, drawPaint);
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
canvasBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
drawCanvas = new Canvas(canvasBitmap);
}
#Override
public boolean onTouchEvent(MotionEvent event) {
float eventX = event.getX();
float eventY = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
drawPath.moveTo(eventX, eventY);
break;
case MotionEvent.ACTION_MOVE:
drawPath.lineTo(eventX, eventY);
break;
case MotionEvent.ACTION_UP:
drawCanvas.drawPath(drawPath, drawPaint);
drawPath.reset();
break;
default:
return false;
}
// Makes our view repaint and call onDraw
invalidate();
return true;
}
public void setErase() {
canvasBitmap.eraseColor(Color.TRANSPARENT);
drawPath.reset();
invalidate();
}
public void startNew() {
drawCanvas.drawColor(0, PorterDuff.Mode.CLEAR);
invalidate();
}
}
3) create drawing object
DrawingArea mDrawView = (DrawingArea) findViewById(R.id.drawing);

Related

How to clear previously drawn canvas on custom ImageView android?

I have a custom ImageView where user can draw using some colors.
I load image from server then allow user to draw on top of it.
When i load the next image , i want the previously drawn colors to be gone before user can draw again.
I tried many thing from internet but not able to achieve the same.
below is code for custom ImageView:
public class DrawingView extends androidx.appcompat.widget.AppCompatImageView {
//drawing path
static Path drawPath;
//drawing and canvas paint
private Paint drawPaint, canvasPaint;
//initial color
static int paintColor = 0xFFFFFFFF;
//stroke width
private float STROKE_WIDTH = 5f;
//canvas
private Canvas drawCanvas;
//canvas bitmap
private Bitmap canvasBitmap;
//eraser mode
private boolean erase = false;
private boolean cc = false;
//constructor
public DrawingView(Context context, AttributeSet attrs) {
super(context, attrs);
setupDrawing();
setErase(erase);
}
private void setupDrawing() {
drawPath = new Path();
drawPaint = new Paint();
drawPaint.setColor(paintColor);
drawPaint.setAntiAlias(true);
drawPaint.setStrokeWidth(STROKE_WIDTH);
drawPaint.setStyle(Paint.Style.STROKE);
drawPaint.setStrokeJoin(Paint.Join.ROUND);
drawPaint.setStrokeCap(Paint.Cap.ROUND);
canvasPaint = new Paint(Paint.DITHER_FLAG);
}
//*************************************** View assigned size ****************************************************
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
canvasBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
drawCanvas = new Canvas(canvasBitmap);
}
public void setPaintColor(int paintColor) {
this.paintColor = paintColor;
setupDrawing();
}
public void setImageOnImageview(Bitmap canvasBitmap) {
this.canvasBitmap = canvasBitmap;
}
#Override
public void setImageResource(int resId) {
super.setImageResource(resId);
}
public void setErase(boolean isErase) {
erase = isErase;
drawPaint = new Paint();
if (erase) {
setupDrawing();
int srcColor = getResources().getColor(R.color.white);
PorterDuff.Mode mode = PorterDuff.Mode.CLEAR;
PorterDuffColorFilter porterDuffColorFilter = new PorterDuffColorFilter(srcColor, mode);
drawPaint.setColorFilter(porterDuffColorFilter);
drawPaint.setColor(srcColor);
drawPaint.setXfermode(new PorterDuffXfermode(mode));
} else {
setupDrawing();
}
}
//************************************ draw view *************************************************************
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (cc) {
canvas.drawBitmap(canvasBitmap, 0, 0, canvasPaint);
canvas.drawPath(drawPath, drawPaint);
cc = false;
} else {
canvas.drawBitmap(canvasBitmap, 0, 0, canvasPaint);
canvas.drawPath(drawPath, drawPaint);
}
}
public void clearCanvas() {
setupDrawing();
setErase(false);
cc = true;
invalidate();
}
//*************************** respond to touch interaction **************************************************
#Override
public boolean onTouchEvent(MotionEvent event) {
canvasPaint.setColor(paintColor);
float touchX = event.getX();
float touchY = event.getY();
//respond to down, move and up events
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
drawPath.moveTo(touchX, touchY);
break;
case MotionEvent.ACTION_MOVE:
drawCanvas.drawPath(drawPath, drawPaint);
drawPath.lineTo(touchX, touchY);
break;
case MotionEvent.ACTION_UP:
drawPath.lineTo(touchX, touchY);
drawCanvas.drawPath(drawPath, drawPaint);
drawPath.reset();
break;
default:
return false;
}
//redraw
invalidate();
return true;
}
//*********************************** return current alpha ***********************************************
public int getPaintAlpha() {
return Math.round((float) STROKE_WIDTH / 255 * 100);
}
//************************************** set alpha ******************************************************
public void setPaintAlpha(int newAlpha) {
STROKE_WIDTH = Math.round((float) newAlpha / 100 * 255);
drawPaint.setStrokeWidth(newAlpha);
}
}
I tried many solutions like clear path or clear paint.
Could any please help me with this ?
I assume you want to remove the drawn color on first image upon loading the new image
I think you can draw the color over canvas
Canvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR)
or reset the path itself
Path.reset();

eraser not working on transparent canvas view android

I made canvas view transparent and code is following;
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.OVERLAY);
}
The following code for eraser and its not working
if (this.mode == Mode.ERASER) {
// Eraser
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
paint.setARGB(0, 255, 0, 0);
paint.setColor(eraserColor);
paint.setStrokeWidth(DrawingActivity.eraserSize);
}
here is full code. Try it.
public class TryDraw extends View {
private Path drawPath;
private Paint drawPaint;
private Paint canvasPaint;
private Canvas drawCanvas;
public static Bitmap canvasBitmap;
private boolean erase=false;
float touchX;
float touchY;
float strokeWidth;
public TryDraw(Context context, AttributeSet attrs) {
super(context, attrs);
}
public void setupDrawing(){
strokeWidth=getResources().getDimension(R.dimen.medium_brush);
drawPath = new CustomPath();
drawPaint = new Paint(Paint.ANTI_ALIAS_FLAG|Paint.DITHER_FLAG);
drawPaint.setColor(Color.RED);
drawPaint.setAntiAlias(true);
drawPaint.setStrokeWidth(strokeWidth);
drawPaint.setStyle(Paint.Style.STROKE);
drawPaint.setStrokeJoin(Paint.Join.ROUND);
drawPaint.setStrokeCap(Paint.Cap.ROUND);
canvasPaint = new Paint(Paint.DITHER_FLAG);
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
canvasBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
drawCanvas = new Canvas(canvasBitmap);
drawCanvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.OVERLAY);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawBitmap(canvasBitmap,0,0, canvasPaint);
canvas.drawPath(drawPath, drawPaint);
}
#Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
drawPath.moveTo(event.getX(),event.getY());
touchX = event.getX();
touchY = event.getY();
drawPath.lineTo(touchX,touchY);
break;
case MotionEvent.ACTION_MOVE:
drawPath.lineTo(event.getX(), event.getY());
touchX = event.getX();
touchY = event.getY();
break;
case MotionEvent.ACTION_UP:
drawCanvas.drawPath(drawPath, drawPaint);
drawPath=new Path();
break;
default:
return false;
}
invalidate();
return true;
}
public void setColor(int newColor){
invalidate();
drawPaint.setColor(newColor);
}
public void setErase(boolean isErase){
if(!isErase) {
drawPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
drawPaint.setStrokeWidth(45.0f);
erase=true;
}else {
drawPaint.setXfermode(null);
drawPaint.setStrokeWidth(strokeWidth);
erase=false;
}
}
public void startNew(){
mDrawingList.clear();
drawCanvas.drawColor(0, PorterDuff.Mode.CLEAR);
invalidate();
}
}

Creating a custom edittext to add functinality of drawing in it

I have created my own custom edittext class so that i can draw in it and also add text...
Everything is working fine regarding the drawing part but when i type no text is visible,,,,,,
How can i fix this
my customview
public class MyCustomView extends View
{
private Path drawPath;
//drawing and canvas paint
private Paint drawPaint, canvasPaint;
//initial color
private int paintColor = 0xFF660000;
//canvas
private Canvas drawCanvas;
//canvas bitmap
private Bitmap canvasBitmap;
private float brushSize ;
private boolean erase=false;
public MyCustomView(Context c, AttributeSet attr){
super(c,attr);
setupdraw();
}
public MyEditText(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void setupdraw()
{
drawPath = new Path();
drawPaint = new Paint();
brushSize = 15;
drawPaint.setColor(paintColor);
drawPaint.setAntiAlias(true);
drawPaint.setStrokeWidth(brushSize);
drawPaint.setStyle(Paint.Style.STROKE);
drawPaint.setStrokeJoin(Paint.Join.ROUND);
drawPaint.setStrokeCap(Paint.Cap.ROUND);
canvasPaint = new Paint(Paint.DITHER_FLAG);
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
//view given size
super.onSizeChanged(w, h, oldw, oldh);
canvasBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
drawCanvas = new Canvas(canvasBitmap);
}
#Override
protected void onDraw(Canvas canvas) {
//draw view
canvas.drawBitmap(canvasBitmap, 0, 0, canvasPaint);
canvas.drawPath(drawPath, drawPaint);
}
#Override
public boolean onTouchEvent(MotionEvent event) {
//detect user touch
float touchX = event.getX();
float touchY = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
drawPath.moveTo(touchX, touchY);
break;
case MotionEvent.ACTION_MOVE:
drawPath.lineTo(touchX, touchY);
break;
case MotionEvent.ACTION_UP:
drawCanvas.drawPath(drawPath, drawPaint);
drawPath.reset();
break;
default:
return false;
}
invalidate();
return true;
}
public void setColor(String newColor){
//set color
invalidate();
paintColor = Color.parseColor(newColor);
drawPaint.setColor(paintColor);
}
public void setBrushSize(float newSize){
//update size
float pixelAmount = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
newSize, getResources().getDisplayMetrics());
brushSize=pixelAmount;
drawPaint.setStrokeWidth(brushSize);
}
}
}
my main activity
public class MainActivity extends Activity
{
private MyCustomView myView;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
MyCustomView myView = (MyCustomView) findViewById(R.id.myCustomView);
}
}
main.xml
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:padding="10dp"
android:background="#D06C65">
<com.mycompany.myapp.MyCustomView
android:id="#+id/myCustomView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#EAEAEA"/>
<Button
android:layout_height="wrap_content"
android:text="T"
android:layout_width="wrap_content"
android:layout_gravity="bottom|center"/>
</FrameLayout>
You should call super.onDraw(canvas) after drawing your background stuff. The TextView drawing methods will subsequently handle all the drawing text features (you don't want to recode that).
#Override
protected void onDraw(Canvas canvas) {
canvas.drawBitmap(canvasBitmap, 0, 0, canvasPaint);
canvas.drawPath(drawPath, drawPaint);
super.onDraw(canvas);
}

Load a Image from SDCard to DrawingView

I'm a newbie for android development. I need some help with loading image from SDCard to a drawingView. What I'm trying to achieve here is after loading the image i want to modify the image and save.
So my primary task is to load the image to DrawingView.
Appreciate your help on this.
Thank you.
please use something like this ..this worked for me
YourDrawingView jpgView = (YourDrawingView)findViewById(R.id.imageView);
Bitmap bitmap = BitmapFactory.decodeFile("/sdcard/sample-1.jpg");
jpgView.setImageBitmap(bitmap);
setContentView(R.layout.main);
and here is my DrawingView
public class DrawingView extends ImageView {
private boolean erase = false;
//drawing path
private Path drawPath;
//drawing and canvas paint
private Paint drawPaint, canvasPaint;
//initial color
private int paintColor = 0xFF660000;
//canvas
private Canvas drawCanvas;
//canvas bitmap
private Bitmap canvasBitmap;
private float brushSize, lastBrushSize;
public DrawingView(Context context, AttributeSet attrs) {
super(context, attrs);
setUpDrawing();
}
public DrawingView(Context context) {
super(context);
}
private void setUpDrawing() {
drawPath = new Path();
drawPaint = new Paint();
drawPaint.setColor(paintColor);
drawPaint.setAntiAlias(true);
drawPaint.setStrokeWidth(20);
drawPaint.setStyle(Paint.Style.STROKE);
drawPaint.setStrokeJoin(Paint.Join.ROUND);
drawPaint.setStrokeCap(Paint.Cap.ROUND);
canvasPaint = new Paint(Paint.DITHER_FLAG);
brushSize = getResources().getInteger(R.integer.medium_size);
lastBrushSize = brushSize;
drawPaint.setStrokeWidth(brushSize);
}
public void setErase(boolean isErase) {
//set erase true or false
erase = isErase;
if (erase) drawPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
else drawPaint.setXfermode(null);
}
public void setBrushSize(float newSize) {
//update size
float pixelAmount = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
newSize, getResources().getDisplayMetrics());
brushSize = pixelAmount;
drawPaint.setStrokeWidth(brushSize);
}
public void setLastBrushSize(float lastSize) {
lastBrushSize = lastSize;
}
public float getLastBrushSize() {
return lastBrushSize;
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
canvasBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
drawCanvas = new Canvas(canvasBitmap);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawBitmap(canvasBitmap, 0, 0, canvasPaint);
canvas.drawPath(drawPath, drawPaint);
}
#Override
public boolean onTouchEvent(MotionEvent event) {
float touchX = event.getX();
float touchY = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
drawPath.moveTo(touchX, touchY);
break;
case MotionEvent.ACTION_MOVE:
drawPath.lineTo(touchX, touchY);
break;
case MotionEvent.ACTION_UP:
drawCanvas.drawPath(drawPath, drawPaint);
drawPath.reset();
break;
default:
break;
}
invalidate();
return true;
}
public void setColor(String color) {
invalidate();
paintColor = Color.parseColor(color);
drawPaint.setColor(paintColor);
}
public void startNew() {
drawCanvas.drawColor(0, PorterDuff.Mode.CLEAR);
invalidate();
}
}
Not sure what is DrawingView, or do you mean ImageView?
File imageFile = new File("/sdcard/my_photo_1.jpg");
Bitmap bitmap = BitmapFactory.decodeFile(imageFile.getAbsolutePath());
imageView.setImageBitmap(bitmap);
You can use canvas to draw image, Below is code :
public class Keypaint extends View {
Paint p;
Bitmap bitmap = null;
public Keypaint(Context context) {
super(context);
File imageFile = new File("/sdcard/my_photo_1.jpg");
bitmap = BitmapFactory.decodeFile(imageFile.getAbsolutePath());
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
p=new Paint();
p.setColor(Color.RED);
canvas.drawBitmap(bitmap, 0, 0, p);
}
}

android capture gesture and draw on canvas, incomplete draw

I'm creating an app where the user draws a letter on canvas and it gets validated if the draw is an actual letter. I'm using a GestureOverlayView with a canvas inside to capture both the gesture and the path, the problem is that the canvas is not drawing the whole path/gesture i do with my hands. I need help to find the solution. I need the path/gesture to be fully drawn.
XML:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<android.gesture.GestureOverlayView
android:id="#+id/gestures"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:eventsInterceptionEnabled="true"
android:gestureStrokeType="multiple"
android:layout_alignParentRight="true"
android:fadeOffset="500"
android:background="#000000">
<cohen.projetoTEA.com.DrawLetter
android:id="#+id/drawing"
android:layout_width="wrap_content"
android:layout_alignParentRight="true"
android:layout_height="wrap_content"
android:background="#FFFFFF"
/>
</android.gesture.GestureOverlayView>
</RelativeLayout>
Activity
public class Reconhecimento extends Activity implements OnGesturePerformedListener {
GestureLibrary mLibrary;
private final File mStoreFile = new File(Environment.getExternalStorageDirectory(), "gestures");
/**
* Called when the activity is first created.
*/
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.reconhecimento);
//mLibrary = GestureLibraries.fromRawResource(this, R.raw.gestures);
mLibrary = GestureLibraries.fromFile(mStoreFile);
if (!mLibrary.load()) {
finish();
}
GestureOverlayView gestures = (GestureOverlayView) findViewById(R.id.gestures);
gestures.addOnGesturePerformedListener(this);
gestures.setGestureVisible(false);
}
public void onGesturePerformed(GestureOverlayView overlay, Gesture gesture) {
ArrayList<Prediction> predictions = mLibrary.recognize(gesture);
if (predictions.size() > 0 && predictions.get(0).score > 1.0) {
String result = predictions.get(0).name;
Toast.makeText(this, result, Toast.LENGTH_LONG).show();
if ("open".equalsIgnoreCase(result)) {
Toast.makeText(this, "Opening the document", Toast.LENGTH_LONG).show();
} else if ("save".equalsIgnoreCase(result)) {
Toast.makeText(this, "Saving the document", Toast.LENGTH_LONG).show();
}
}
}
}
DrawLetter app
public class DrawLetter extends View {
//drawing path
private Path drawPath;
//drawing and canvas paint
private Paint drawPaint, canvasPaint;
//initial color
private int paintColor = 0xFF660000;
//canvas
private Canvas drawCanvas;
//canvas bitmap
private Bitmap canvasBitmap;
private boolean erase=false;
public DrawLetter(Context context, AttributeSet attrs){
super(context, attrs);
setupDrawing();
}
private void setupDrawing(){
drawPath = new Path();
drawPaint = new Paint();
drawPaint.setColor(paintColor);
drawPaint.setAntiAlias(true);
drawPaint.setStrokeWidth(5);
drawPaint.setStyle(Paint.Style.STROKE);
drawPaint.setStrokeJoin(Paint.Join.ROUND);
drawPaint.setStrokeCap(Paint.Cap.ROUND);
canvasPaint = new Paint(Paint.DITHER_FLAG);
}
public void setErase(boolean isErase){
erase=isErase;
if(erase){
drawPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
drawPaint.setStrokeWidth(10);
}
else{
drawPaint.setXfermode(null);
drawPaint.setStrokeWidth(5);
}
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
//view given size
super.onSizeChanged(w, h, oldw, oldh);
canvasBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
drawCanvas = new Canvas(canvasBitmap);
}
#Override
protected void onDraw(Canvas canvas) {
//draw view
canvas.drawBitmap(canvasBitmap, 0, 0, canvasPaint);
canvas.drawPath(drawPath, drawPaint);
}
#Override
public boolean onTouchEvent(MotionEvent event) {
//detect user touch
float touchX = event.getX();
float touchY = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
drawPath.moveTo(touchX, touchY);
break;
case MotionEvent.ACTION_MOVE:
drawPath.lineTo(touchX, touchY);
break;
case MotionEvent.ACTION_UP:
drawCanvas.drawPath(drawPath, drawPaint);
drawPath.reset();
break;
default:
return false;
}
invalidate();
return true;
}
public boolean getErase(){ return erase; }
}
You can do it in another way.
Like this
<android.gesture.GestureOverlayView
android:id="#+id/g1"
android:layout_width="fill_parent"
android:layout_height="200dp"
android:background="#ffffff"
android:fadeOffset="999999"
android:gestureColor="#0000FF"
android:gestureStrokeType="multiple"
android:gestureStrokeWidth="5" >
<android.gesture.GestureOverlayView
android:id="#+id/g2"
android:layout_width="fill_parent"
android:layout_height="200dp"
android:gestureStrokeType="multiple"
android:fadeOffset="001"
android:gestureColor="#000"
android:gestureStrokeAngleThreshold="0.0"
android:gestureStrokeLengthThreshold="0.0"
android:gestureStrokeSquarenessThreshold="0.0"
>
</android.gesture.GestureOverlayView>
</android.gesture.GestureOverlayView>
Here GestureOverlayView g2 is within g1.
g2 is used to recognize letters and it fades once the letter is written.
But g1 does not fades.
If you don't want the letter you can clear the GestureOverlayView.

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