Develop Reference

How to draw a custom shape using multiple lines

I wanted to draw the custom shape using multiple straight lines. For that, i used the canvas. But I can draw only one line. When I draw second, previous disappears.
My code is given.
public class CanvasBackground extends View {
public Paint paint;
public Context context;
public Canvas canvas;
public ScaleGestureDetector scaleGestureDetector;
float scalfactor = 1f;
boolean isDrawing;
private PointF startPoint, endPoint;
public CanvasBackground(Context context) {
super(context);
this.context = context;
paint = new Paint();
scaleGestureDetector = new ScaleGestureDetector(context, new CanvasScale());
setDrawingCacheEnabled(true);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
this.canvas = canvas;
paint.setColor(Color.WHITE);
canvas.drawPaint(paint);
canvas.save();
DrawingZoomingCanvas(canvas);
DrawingLine(canvas);
canvas.restore();
Log.e("OnDraw >>>", "CALLING");
}
#Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
startPoint = new PointF(event.getX(), event.getY());
endPoint = new PointF();
isDrawing = true;
break;
case MotionEvent.ACTION_MOVE:
if (isDrawing) {
endPoint.x = event.getX();
endPoint.y = event.getY();
invalidate();
}
break;
case MotionEvent.ACTION_UP:
if (isDrawing) {
endPoint.x = event.getX();
endPoint.y = event.getY();
//isDrawing = false;
invalidate();
}
break;
default:
break;
}
//scaleGestureDetector.onTouchEvent(event);
Log.e("OnTouch >>>", "CALLING" + isDrawing);
return true;
}
//drawing Matrix Canvas With Zoom
private void DrawingZoomingCanvas(Canvas canvas) {
//drawing Matarix
canvas.translate(scalfactor * 10, scalfactor * 10);
canvas.scale(scalfactor, scalfactor);
paint.setColor(Color.rgb(220, 220, 220));
for (int i = 0; i <= canvas.getHeight() * scalfactor; i += 10) {
canvas.drawLine(i, 0, i, canvas.getHeight(), paint);
canvas.drawLine(0, i, canvas.getWidth(), i, paint);
}
}
//drawing a line
private void DrawingLine(Canvas canvas) {
paint = new Paint();
paint.setColor(Color.RED);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(2);
paint.setAntiAlias(true);
if (isDrawing)
canvas.drawLine(startPoint.x, startPoint.y, endPoint.x, endPoint.y, paint);
}
private class CanvasScale extends ScaleGestureDetector.SimpleOnScaleGestureListener {
#Override
public boolean onScale(ScaleGestureDetector detector) {
scalfactor *= scaleGestureDetector.getScaleFactor();
scalfactor = Math.max(0.1f, Math.min(scalfactor, 10.0f));
invalidate();
return true;
}
}
}

You are clearing your canvas each time you draw a line, so the previous line will be erased as you draw the new one.
You need to store the previous lines in a bitmap so you can draw these when you draw the new one.

Android - How to change color in setColor

I want to create a drawing app, and it works clearly but it is still far away from my goal.
Here's my code:
public class MainActivity extends Activity {
DrawingView dv;
private Paint mPaint;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
dv = new DrawingView(this);
setContentView(dv);
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setDither(true);
mPaint.setColor(Color.BLUE);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(5);
}
public class DrawingView extends View {
public int width;
public int height;
private Bitmap mBitmap;
private Canvas mCanvas;
private Path mPath;
private Paint mBitmapPaint;
Context context;
private Paint circlePaint;
private Path circlePath;
public DrawingView(Context c) {
super(c);
context = c;
mPath = new Path();
mBitmapPaint = new Paint(Paint.DITHER_FLAG);
circlePaint = new Paint();
circlePath = new Path();
circlePaint.setAntiAlias(true);
circlePaint.setColor(Color.RED);
circlePaint.setStyle(Paint.Style.STROKE);
circlePaint.setStrokeJoin(Paint.Join.MITER);
circlePaint.setStrokeWidth(4f);
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
//mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
mBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.asd) //-->here load your image
.copy(Bitmap.Config.ARGB_8888, true);
mCanvas = new Canvas(mBitmap);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
canvas.drawPath(mPath, mPaint);
canvas.drawPath(circlePath, circlePaint);
}
private float mX, mY;
private static final float TOUCH_TOLERANCE = 4;
private void touch_start(float x, float y) {
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
}
private void touch_move(float x, float y) {
float dx = Math.abs(x - mX);
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
mPath.quadTo(mX, mY, (x + mX) / 2, (y + mY) / 2);
mX = x;
mY = y;
circlePath.reset();
circlePath.addCircle(mX, mY, 30, Path.Direction.CW);
}
}
private void touch_up() {
mPath.lineTo(mX, mY);
circlePath.reset();
// commit the path to our offscreen
mCanvas.drawPath(mPath, mPaint);
// kill this so we don't double draw
mPath.reset();
}
#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();
invalidate();
break;
}
return true;
}
}
}
public class FingerPaintActivity extends Activity
implements ColorPickerDialog.OnColorChangedListener{
MyView mv;
AlertDialog dialog;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mv= new MyView(this);
mv.setDrawingCacheEnabled(true);
mv.setBackgroundResource(R.drawable.afor);//set the back ground if you wish to
setContentView(mv);
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setDither(true);
mPaint.setColor(0xFFFF0000);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(20);
mEmboss = new EmbossMaskFilter(new float[] { 1, 1, 1 },
0.4f, 6, 3.5f);
mBlur = new BlurMaskFilter(8, BlurMaskFilter.Blur.NORMAL);
}
private Paint mPaint;
private MaskFilter mEmboss;
private MaskFilter mBlur;
public void colorChanged(int color) {
mPaint.setColor(color);
}
public class MyView extends View {
private static final float MINP = 0.25f;
private static final float MAXP = 0.75f;
private Bitmap mBitmap;
private Canvas mCanvas;
private Path mPath;
private Paint mBitmapPaint;
Context context;
public MyView(Context c) {
super(c);
context=c;
mPath = new Path();
mBitmapPaint = new Paint(Paint.DITHER_FLAG);
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
//mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
mBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.asd) //-->here load your image
.copy(Bitmap.Config.ARGB_8888, true);
mCanvas = new Canvas(mBitmap);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
canvas.drawPath(mPath, mPaint);
}
private float mX, mY;
private static final float TOUCH_TOLERANCE = 4;
private void touch_start(float x, float y) {
//showDialog();
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
}
private void touch_move(float x, float y) {
float dx = Math.abs(x - mX);
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
mPath.quadTo(mX, mY, (x + mX)/2, (y + mY)/2);
mX = x;
mY = y;
}
}
private void touch_up() {
mPath.lineTo(mX, mY);
// commit the path to our offscreen
mCanvas.drawPath(mPath, mPaint);
// kill this so we don't double draw
mPath.reset();
mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SCREEN));
//mPaint.setMaskFilter(null);
}
#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();
invalidate();
break;
}
return true;
}
}
}
This is what my app looks like:
I want to change color draw from blue to brown. I changed mPaint.setColor(Color.BROWN); and it failed.
If you check my preview app, you'll see that I want to create a business logic where: If user is drawing and it's not completed, the app will show a message like "sorry you have not finished the drawing" and I still look for the way to do it. I don't know if it's possible, is it?

Try using the following line:
mPaint.setColor(ContextCompat.getColor(context, R.color.your_color));

I presume that your main question is how to change color programmatically, right?
just change:
mPaint.setColor(Color.BROWN);
to:
mPaint.setColor(getResources().getColor(R.color.Brown));
I think it can help you

How to take first touch co-ordinates

How to take first touch coordinates and make it constant.
I wanna click something on screen then draw a permanent on first touch and then want to move another circle within the the permanent circle one
hers the code am trying :
public class MainActivity extends Activity implements OnTouchListener {
private float x;
private float y;
static float lasttouchx;
static float lasttouchy;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
MyCustomPanel view = new MyCustomPanel(this);
ViewGroup.LayoutParams params =
new ViewGroup.LayoutParams(LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT);
addContentView(view, params);
view.setOnTouchListener(this);
}
private class MyCustomPanel extends View {
public MyCustomPanel(Context context) {
super(context);
}
#Override
public void draw(Canvas canvas) {
super.draw(canvas);
Paint paint = new Paint();
paint.setColor(Color.BLACK);
paint.setStrokeWidth(5);
paint.setTextSize(50);
canvas.drawText(" X : " + (int) x + " Y : " + (int) y, canvas.getWidth() - 500, 200, paint);
paint.setStyle(Paint.Style.FILL);
if((x<=1000&& x>=18)&&(y<=1380&&y>=348)){
paint.setColor(Color.BLUE);
canvas.drawCircle(x, y, 100, paint);
paint.setColor(Color.BLACK);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(20);
canvas.drawCircle(lasttouchx, lasttouchy, 500, paint);
}
else{}
}
}
#Override
public boolean onTouch(View v, MotionEvent event) {
x = event.getX();
y = event.getY();
int action = event.getActionMasked();
switch (action){
case MotionEvent.ACTION_DOWN:
lasttouchx = event.getX();
lasttouchy = event.getY();
return false;
}
v.invalidate();
return true;
}
}

Override onTouchEvent(MotionEvent event) and then call event.getX() and event.getY() to get the coordinate positions of where the user touched.
then store value to some variable.
now use these values you want and try replacing to another.
Check stack answer to get touch screen information answer

Android Drawing, Erasing and Undoing Action

Here is the code for Drawing and Undoing but unable to join with Erasing.
It is either Drawing + Erasing or Drawing + Undoing but cannot three of these.
public class Drawing extends View {
private Paint mPaint, mBitmapPaint;
private Bitmap mBitmap;
private Canvas mCanvas;
private Path mPath;
private float mX, mY;
private static final float TOUCH_TOLERANCE = 4;
private int color, size, state;
private ArrayList<Path> paths = new ArrayList<Path>();
private ArrayList<Path> undonePaths = new ArrayList<Path>();
private ArrayList<Integer> colors = new ArrayList<Integer>();
private ArrayList<Integer> sizes = new ArrayList<Integer>();
public Drawing(Context c) {
super(c);
}
public Drawing(Context c,int width, int height, int size, int color, int state) {
super(c);
mBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
mCanvas = new Canvas(mBitmap);
mPath = new Path();
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setDither(true);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
// mBitmapPaint = new Paint(Paint.DITHER_FLAG);
// mBitmapPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC));
setColor(color);
setSize(size);
setState(state);
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
}
#Override
protected void onDraw(Canvas canvas) {
// canvas.drawColor(Color.TRANSPARENT);
// canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
//
// if (state == 0)
// mBitmap.eraseColor(Color.TRANSPARENT);
for (int i = 0; i < paths.size(); i++) {
mPaint.setColor(colors.get(i));
mPaint.setStrokeWidth(sizes.get(i));
canvas.drawPath(paths.get(i), mPaint);
}
mPaint.setColor(color);
mPaint.setStrokeWidth(size);
canvas.drawPath(mPath, mPaint);
}
public void setColor(int color) {
this.color = color;
}
public void setSize(int size) {
this.size = size;
}
public void setState(int state) {
this.state = state;
// if (state == 0)
// mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
// else
// mPaint.setXfermode(null);
}
public void onClickUndo() {
if (paths.size() > 0) {
undonePaths.add(paths.remove(paths.size() - 1));
sizes.remove(sizes.size() - 1);
colors.remove(colors.size() - 1);
invalidate();
}
}
private void touch_start(float x, float y) {
undonePaths.clear();
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
}
private void touch_move(float x, float y) {
float dx = Math.abs(x - mX);
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
mPath.quadTo(mX, mY, (x + mX) / 2, (y + mY) / 2);
mX = x;
mY = y;
}
}
private void touch_up() {
mPath.lineTo(mX, mY);
mCanvas.drawPath(mPath, mPaint);
colors.add(color);
sizes.add(size);
paths.add(mPath);
mPath = new Path();
}
#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();
invalidate();
break;
}
return true;
}
}
I tried to made color to transparent but it does not make sense because not changing the pixel but is create new path.

The below can be used to draw erase, emboss, save to gallery, blur. You can use the code to add undo and redo functionality. The below code works fine. You can slo check FingerPaint.java from the samples folder of your adk under api demos in the grapics folder.
Creating a spray effect on touch draw in android. This link will help you create spray effect by spraying dots.
public class FingerPaintActivity extends GraphicsActivity
implements ColorPickerDialog.OnColorChangedListener {
private Paint mPaint;
private MaskFilter mEmboss;
private MaskFilter mBlur;
Button b;
Dialog dialog;
static MyView mv;
File f;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
LinearLayout ll = (LinearLayout) findViewById(R.id.ll);
mv= new MyView(this);
mv.setDrawingCacheEnabled(true);
ll.addView(mv);
b= (Button) findViewById(R.id.button1);
b.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
final CharSequence[] items = {"Pick Color", "Emboss", "Blur","Erase","SaveToGallery"};
AlertDialog.Builder builder = new AlertDialog.Builder(FingerPaintActivity.this);
builder.setTitle("Options");
builder.setItems(items, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int item) {
if(item==0)
{
new ColorPickerDialog(FingerPaintActivity.this, FingerPaintActivity.this, mPaint.getColor()).show();
}
if(item==1)
{
if (mPaint.getMaskFilter() != mEmboss) {
mPaint.setMaskFilter(mEmboss);
} else {
mPaint.setMaskFilter(null);
}
}
if(item==2)
{
if (mPaint.getMaskFilter() != mBlur) {
mPaint.setMaskFilter(mBlur);
} else {
mPaint.setMaskFilter(null);
}
}
if(item==3)
{
mPaint.setXfermode(new PorterDuffXfermode(
PorterDuff.Mode.CLEAR));
}
if(item==4)
{
saveImage();
}
}
});
builder.show();
}
});
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setDither(true);
mPaint.setColor(0xFFFF0000);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(20);
mEmboss = new EmbossMaskFilter(new float[] { 1, 1, 1 },
0.4f, 6, 3.5f);
mBlur = new BlurMaskFilter(8, BlurMaskFilter.Blur.NORMAL);
}
public void colorChanged(int color) {
mPaint.setColor(color);
}
public class MyView extends View {
private static final float MINP = 0.25f;
private static final float MAXP = 0.75f;
private Bitmap mBitmap;
private Canvas mCanvas;
private Path mPath;
private Paint mBitmapPaint;
Context mcontext;
public MyView(Context c) {
super(c);
mcontext=c;
mPath = new Path();
mBitmapPaint = new Paint();
mBitmapPaint.setColor(Color.RED);
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
mCanvas = new Canvas(mBitmap);
}
#Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(0xFFAAAAAA);
Display display = ( (Activity) mcontext).getWindowManager().getDefaultDisplay();
float w = display.getWidth();
float h = display.getHeight();
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
canvas.drawLine(0, 0, w, 0,mBitmapPaint);
canvas.drawLine(0, 0, 0, h,mBitmapPaint);
canvas.drawLine(w,h,w,0,mBitmapPaint);
canvas.drawLine(w, h, 0,h , mBitmapPaint);
canvas.drawPath(mPath, mPaint);
}
private float mX, mY;
private static final float TOUCH_TOLERANCE = 4;
private void touch_start(float x, float y) {
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
}
private void touch_move(float x, float y) {
float dx = Math.abs(x - mX);
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
mPath.quadTo(mX, mY, (x + mX)/2, (y + mY)/2);
mX = x;
mY = y;
}
}
private void touch_up() {
mPath.lineTo(mX, mY);
// commit the path to our offscreen
mCanvas.drawPath(mPath, mPaint);
mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SCREEN));
// kill this so we don't double draw
mPath.reset();
}
#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();
invalidate();
break;
}
return true;
}
}
public void saveImage()
{
AlertDialog.Builder editalert = new AlertDialog.Builder(FingerPaintActivity.this);
editalert.setTitle("Please Enter the name with which you want to Save");
final EditText input = new EditText(FingerPaintActivity.this);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.FILL_PARENT,
LinearLayout.LayoutParams.FILL_PARENT);
input.setLayoutParams(lp);
editalert.setView(input);
editalert.setPositiveButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
mv.setDrawingCacheEnabled(true);
String name= input.getText().toString();
Bitmap bitmap = mv.getDrawingCache();
String root = Environment.getExternalStorageDirectory().toString();
File myDir = new File(root + "/MapleBearDraw");
myDir.mkdirs();
File file = new File (myDir, name+".jpg");
if (file.exists ()) file.delete ();
try
{
if(!file.exists())
{
file.createNewFile();
}
FileOutputStream ostream = new FileOutputStream(file);
bitmap.compress(CompressFormat.JPEG, 50, ostream);
ostream.flush();
ostream.close();
mv.invalidate();
}
catch (Exception e)
{
e.printStackTrace();
}finally
{
mv.setDrawingCacheEnabled(false);
}
}
});
editalert.show();
}
private static final int COLOR_MENU_ID = Menu.FIRST;
private static final int EMBOSS_MENU_ID = Menu.FIRST + 1;
private static final int BLUR_MENU_ID = Menu.FIRST + 2;
private static final int ERASE_MENU_ID = Menu.FIRST + 3;
private static final int SRCATOP_MENU_ID = Menu.FIRST + 4;
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
menu.add(0, COLOR_MENU_ID, 0, "Color").setShortcut('3', 'c');
menu.add(0, EMBOSS_MENU_ID, 0, "Emboss").setShortcut('4', 's');
menu.add(0, BLUR_MENU_ID, 0, "Blur").setShortcut('5', 'z');
menu.add(0, ERASE_MENU_ID, 0, "Erase").setShortcut('5', 'z');
menu.add(0, SRCATOP_MENU_ID, 0, "SrcATop").setShortcut('5', 'z');
/**** Is this the mechanism to extend with filter effects?
Intent intent = new Intent(null, getIntent().getData());
intent.addCategory(Intent.CATEGORY_ALTERNATIVE);
menu.addIntentOptions(
Menu.ALTERNATIVE, 0,
new ComponentName(this, NotesList.class),
null, intent, 0, null);
*****/
return true;
}
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
super.onPrepareOptionsMenu(menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
mPaint.setXfermode(null);
mPaint.setAlpha(0xFF);
switch (item.getItemId()) {
case COLOR_MENU_ID:
new ColorPickerDialog(FingerPaintActivity.this, this, mPaint.getColor()).show();
return true;
case EMBOSS_MENU_ID:
if (mPaint.getMaskFilter() != mEmboss) {
mPaint.setMaskFilter(mEmboss);
} else {
mPaint.setMaskFilter(null);
}
return true;
case BLUR_MENU_ID:
if (mPaint.getMaskFilter() != mBlur) {
mPaint.setMaskFilter(mBlur);
} else {
mPaint.setMaskFilter(null);
}
return true;
case ERASE_MENU_ID:
mPaint.setXfermode(new PorterDuffXfermode(
PorterDuff.Mode.CLEAR));
return true;
case SRCATOP_MENU_ID:
mPaint.setXfermode(new PorterDuffXfermode(
PorterDuff.Mode.SRC_ATOP));
mPaint.setAlpha(0x80);
return true;
}
return super.onOptionsItemSelected(item);
}
}

How to draw the multiple lines with different color and undo,redo the paths in android?

I want to draw multiple lines on the view with different colors and undo,redo the paths in android.
I use the bitmap paint option, each path has a unique color but undo,redo is not working.
Here is my code of bitmappaint:
public MyView(Context context, Object object) {
super(context);
setFocusable(true);
setFocusableInTouchMode(true);
mPath = new Path();
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setColor(0xFFFFFF00);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(3);
mBitmap = Bitmap.createBitmap(320, 480, Bitmap.Config.ARGB_8888);
mCanvas = new Canvas(mBitmap);
}
protected void onSizeChanged(int w, int h, int oldw, int oldh)
{
super.onSizeChanged(w, h, oldw, oldh);
}
protected void onDraw(Canvas canvas)
{
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
for (Path p : paths)
{
canvas.drawPath(p, mPaint);
}
canvas.drawPath(mPath, mPaint);
}
public boolean onTouchEvent(MotionEvent event)
{
float x = event.getX();
float y = event.getY();
int action = event.getAction();
int action1=event.getAction();
switch (event.getAction())
{
case MotionEvent.ACTION_DOWN:
undonePaths.clear();
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
startPoint = new PointF(event.getX(), event.getY());
endPoint = new PointF();
invalidate();
// isDrawing = true;
break;
case MotionEvent.ACTION_MOVE:
float dx = Math.abs(x - mX);
System.out.println("action move");
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE)
{
// currentDrawingPath.path.quadTo(mX,mY,(x + mX)/2, (y + mY)/2);
}
mX = x;
mY = y;
endPoint.x = event.getX();
endPoint.y = event.getY();
isDrawing = true;
invalidate();
break;
case MotionEvent.ACTION_UP:
mPath.lineTo(mX, mY);
paths.add(mPath);
mPath = new Path();
// mCanvas.drawPath(mPath, ppaint);
endPoint.x = event.getX();
endPoint.y = event.getY();
isDrawing = false;
invalidate();
break;
default:
break;
}
}
without bitmap using i faced the color problem if i select a blue color for a path means all the previous paths will be changed to blue color;
Here is my code
protected void onDraw(Canvas canvas)
{
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
for (Path p : paths)
{
canvas.drawPath(p, mPaint);
}
canvas.drawPath(mPath, mPaint);
}
Can anyone help me to draw multiple paths with different color of unique paths in android?

When you handle the MotionEvent.ACTION_UP : you need to save the color used to draw the path with something like this :
case MotionEvent.ACTION_UP:
paths.add(mPath);
colorsMap.put(mPath,selectedColor); // store the color of mPath
...
Before drawing a path, you need to set the paint color:
protected void onDraw(Canvas canvas) {
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
for (Path p : paths)
{
mPaint.setColor(colorsMap.get(p));
canvas.drawPath(p, mPaint);
}
mPaint.setColor(selectedColor);
canvas.drawPath(mPath, mPaint);
}
And the colorsMap is a simple instance variable:
private Map<Path, Integer> colorsMap = new HashMap<Path, Integer>();
To implement the Undo/Redo feature, you just have to remove the last element from paths (and store it in a undoneList so that on redo can restore it). see Android Canvas Redo and Undo Operation

this working code .I test it on my own app and it is working very good.
May be it help u.Please comment on it.
public class Main extends Activity implements OnColorChangedListener {
//public static int selectedColor = Color.BLACK;
public static ArrayList<Path> mMaindialog;
// private ArrayList<Path> undonePaths;
// public int selectedcolor;
private static final String COLOR_PREFERENCE_KEY = "color";
private FrameLayout relativelayout;
static String sdpath,location;
Boolean i;
// Instance variables
private Bitmap mBitmap=null;
Bitmap bitmap;
private Paint mPaint, mBitmapPaint, mPaint1;
private MyView mView;
ImageView idd;
// private Path mPath;
int slll = Color.BLACK;
Bitmap map=ListView5.bMap;
private Button ClearPaint, Colorpaint;
Ghostdatabase gost;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
idd=(ImageView)findViewById(R.id.imageView1);
relativelayout = (FrameLayout) findViewById(R.id.frameLayout);
DisplayMetrics metrics = getBaseContext().getResources()
.getDisplayMetrics();
int w = metrics.widthPixels;
int h = metrics.heightPixels;
System.out.println(" width " + w);
System.out.println(" height " + h);
mView = new MyView(this, w, h);
mView.setDrawingCacheEnabled(true);
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(4);
ClearPaint = (Button) findViewById(R.id.ne);
ClearPaint.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// mBitmap.eraseColor(Color.TRANSPARENT);
// mPath.reset();
// mView.invalidate();
mView.onClickUndo();
}
});
Button save22 = (Button) findViewById(R.id.save);
save22.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
File cacheDir;
Toast.makeText(Main.this, "Photo", 500).show();
Bitmap icon;
relativelayout.setDrawingCacheEnabled(true);
icon = Bitmap.createBitmap(relativelayout.getDrawingCache());
Bitmap bitmap = icon;
relativelayout.setDrawingCacheEnabled(false);
// File mFile1 = Environment.getExternalStorageDirectory();
Date d = new Date();
String fileName = d.getTime() + "mg1.jpg";
File storagePath = (Environment.getExternalStorageDirectory());
File dest = new File(storagePath + "/CityAppImages");
if (!dest.exists()) {
dest.mkdirs();
}
File mFile2 = new File(dest, fileName);
sdpath = mFile2.getAbsolutePath();
Log.d("qqqqqqqqqqqqqqqqqqqqqqq", "zzzzzzzz" + sdpath);
try {
FileOutputStream outStream;
outStream = new FileOutputStream(mFile2);
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, outStream);
outStream.flush();
outStream.close();
Toast.makeText(Main.this, "Photo Saved Sucessfully", 500)
.show();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
Toast.makeText(Main.this, "Photo Not Saved Sucessfully",
500).show();
}
gost = new Ghostdatabase(Main.this);
gost.open();
gost.insertTitle(sdpath);
}
});
Button view = (Button) findViewById(R.id.listtt);
view.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent ii = new Intent(Main.this, ListView5.class);
startActivity(ii);
}
});
Button Colorpaint = (Button) findViewById(R.id.Color);
Colorpaint.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
int color = PreferenceManager.getDefaultSharedPreferences(
Main.this).getInt(COLOR_PREFERENCE_KEY, Color.WHITE);
// int _color = R.color.red;
new ColorPickerDialog(v.getContext(),
new OnColorChangedListener() {
public void colorChanged(int color) {
mPaint.setColor(color);
slll = color;
Log.i("TAG", "mpaint one" + mPaint);
}
}, mPaint.getColor()).show();
Log.i("TAG", "mpaint two" + mPaint);
}
});
relativelayout.addView(mView);
}
// //////////******************* Pinting view
// *******************///////////////////
public class MyView extends View implements OnTouchListener {
private Map<Path, Integer> colorsMap = new HashMap<Path, Integer>();
private ArrayList<Path> mMaindialog = new ArrayList<Path>();
private ArrayList<Path> undonePaths = new ArrayList<Path>();
int colorPicked = slll;
// Paint mPaint1;
private Canvas mCanvas;
private Path mPath;
public MyView(Context c, int w, int h) {
super(c);
if(GlobalVariable.impath==1)
{
Log.d("","111111"+GlobalVariable.impath);
System.out.println(GlobalVariable.impath);
Intent ii = getIntent();
location = ii.getStringExtra("IMAGE");
// bitmap.recycle();
Log.d("","location"+location);
bitmap = BitmapFactory.decodeFile(location);
mBitmap = Bitmap.createScaledBitmap(bitmap,300, 300,false);
Log.d("hhhhhhhhhhhhhhhssssssss","mBitmap"+mBitmap);
//mBitmap = Bitmap.createBitmap(100, 100, Bitmap.Config.ARGB_8888);
// idd.setImageBitmap(mBitmap);
Log.d("hhhhhhhhhhhhhhhssssssss","GlobalVariable.impath"+GlobalVariable.impath);
}
else if(GlobalVariable.impath==2){
//bitmap.recycle();
Log.d("","22222222222222222222222"+GlobalVariable.impath);
bitmap=BitmapFactory.decodeResource(getResources(),R.drawable.base);
mBitmap = Bitmap.createScaledBitmap(bitmap,100, 100, false);
//mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
Log.d("hhhhhhhhhhhhhhhssssssss1111111","mBitmap"+mBitmap);
}
//
mCanvas = new Canvas(mBitmap);
mPath = new Path();
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
}
#Override
protected void onDraw(Canvas canvas) {
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
for (Path p : mMaindialog) {
mPaint.setColor(colorsMap.get(p));
canvas.drawPath(p, mPaint);
}
mPaint.setColor(slll);
canvas.drawPath(mPath, mPaint);
}
// //////************touching evants for painting**************///////
private float mX, mY;
private static final float TOUCH_TOLERANCE = 0;
private void touch_start(float x, float y) {
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
undonePaths.clear();
}
private void touch_move(float x, float y) {
float dx = Math.abs(x - mX);
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
mPath.quadTo(mX, mY, (x + mX) / 2, (y + mY) / 2);
mX = x;
mY = y;
}
}
private void touch_up() {
mPath.lineTo(mX, mY);
// commit the path to our offscreen
mCanvas.drawPath(mPath, mPaint);
// kill this so we don't double draw
mPath = new Path();
mPath.reset();
mMaindialog.add(mPath);
}
#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();
undonePaths.clear();
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
invalidate();
break;
case MotionEvent.ACTION_MOVE:
// touch_move(x, y);
// invalidate();
float dx = Math.abs(x - mX);
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
mPath.quadTo(mX, mY, (x + mX) / 2, (y + mY) / 2);
mX = x;
mY = y;
}
invalidate();
break;
case MotionEvent.ACTION_UP:
// touch_up();
// invalidate();
mPath.lineTo(mX, mY);
mMaindialog.add(mPath);
colorsMap.put(mPath, slll);
mPath = new Path();
mPath.reset();
invalidate();
break;
}
return true;
} // end of touch events for image
private Paint createPen(int colorPicked) {
// TODO Auto-generated method stub
mPaint1 = new Paint();
mPaint1.setColor(colorPicked);
mPaint1.setAntiAlias(true);
mPaint1.setDither(true);
mPaint1.setStyle(Paint.Style.STROKE);
mPaint1.setStrokeJoin(Paint.Join.ROUND);
mPaint1.setStrokeCap(Paint.Cap.ROUND);
// mPaint1.setStrokeWidth(3);
return mPaint1;
}
public void onClickRedo() {
if (undonePaths.size() > 0) {
mMaindialog.add(undonePaths.remove(undonePaths.size() - 1));
mView.invalidate();
} else {
}
// toast the user
}
public void onClickUndo() {
if (mMaindialog.size() > 0) {
undonePaths.add(mView.mMaindialog.remove(mView.mMaindialog
.size() - 1));
mView.invalidate();
}
else {
}
}
#Override
public boolean onTouch(View arg0, MotionEvent arg1) {
// TODO Auto-generated method stub
return false;
}
}// end MyView
#Override
public void colorChanged(int color) {
// TODO Auto-generated method stub
PreferenceManager.getDefaultSharedPreferences(this).edit()
.putInt(COLOR_PREFERENCE_KEY, color).commit();
slll = color;
}
}