NewDev
Reputation: 257
Measuring between two points
I have created my own ImageView which hopefully will do overlays , zooming , panning and measuring between two points.
So far all but the measuring works The canvas.drawline shows nothing ?
This may be dirty and could probably be cleaned quite a bit. Anyone got an Idea why the canvas.drawline does not work ?
Thanks in Advance
public class myImage extends ImageView implements OnTouchListener {
private static final short UNKNOWN = 0;
private static final short IMG_INIT = 1;
private static final short SET_IMAGE = 2;
private static final short DRAGGING = 3;
private static final short MARKING = 4;
private static final short STARTING = 5;
private static final short ZOOM_PAN = 6;
private static final short OVERLAY = 7;
private static short STATE = UNKNOWN;
private static PointF pointA = null;
private static PointF pointB = null;
private static PointF pointC = null;
private PointF busy = new PointF();
private Bitmap tracking = BitmapFactory.decodeResource(getResources(), R.drawable.target);
private Drawable[] layers = new Drawable[2];
private Paint mPaint;
private Bitmap mBitmap;
private Canvas busyCanvas;
private int touch_counter = 0;
@Override
protected void onDraw(Canvas canvas) {
switch (STATE) {
/* 0 */ case UNKNOWN: super.onDraw(canvas); break;
/* 1 */ case IMG_INIT: break;
/* 2 */ case SET_IMAGE: super.onDraw(canvas); break;
/* 3 */ case DRAGGING: break;
/* 4 */ case MARKING:
canvas.drawBitmap(mBitmap, matrix, mPaint);
if (touch_counter == 0 && pointB != null && CURRENT_STATUS == "DRAW_LINE" ) {
mPaint.setColor(Color.BLUE);
canvas.drawLine(pointA.x, pointA.y, pointB.x, pointB.y, mPaint);
This is What does Not Show up OR work
}
break;
/* 5 */ case STARTING: break;
/* 6 */ case ZOOM_PAN: super.onDraw(canvas); break;
/* 7 */ case OVERLAY: super.onDraw(canvas); break;
}
STATE = UNKNOWN;
}
public void InitOverlay(String fName) {
fName = "/sdcard/DCIM/"+fName;
if ( (fName.endsWith(".jpg") || fName.endsWith(".png")) ) {
Matrix matrix = new Matrix();
matrix.postScale(0.35f, 0.35f);
Bitmap bitm2 = BitmapFactory.decodeFile( fName );
layers[0] = new BitmapDrawable( mBitmap ); layers[0].setAlpha(255);
layers[1] = new BitmapDrawable( Bitmap.createBitmap(bitm2, 0, 0, bitm2.getWidth(), bitm2.getHeight(), matrix, true) ); layers[1].setAlpha( 50);
LayerDrawable layerDraw = new LayerDrawable(layers);
super.setImageDrawable(layerDraw);
super.invalidate();
STATE = OVERLAY;
}
}
private void OverLay(View view , MotionEvent event) {
if ( STATE == UNKNOWN && event.getAction() == MotionEvent.ACTION_MOVE) {
STATE = OVERLAY;
if ( event.getX() > 1 && event.getX() < 1130 ) {
layers[1].setAlpha( (int) (event.getX() / 4.35f) );
}
}
}
private void AddPoints(View view , MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN: touch_start(event.getX() , event.getY()); break;
case MotionEvent.ACTION_MOVE: touch_busy (event.getX() , event.getY()); break;
case MotionEvent.ACTION_UP: touch_end (event.getX() , event.getY()); break;
}
}
private void touch_start(float x, float y) {
STATE = STARTING;
touch_counter++;
busy.x = ((x - 32.0f + (float)getScrollX()));
busy.y = ((y - 70.0f + (float)getScrollY()));
}
private void touch_busy(float x, float y) {
busy.x = ((x - 32.0f + (float)getScrollX()));
busy.y = ((y - 70.0f + (float)getScrollY()));
STATE = DRAGGING;
}
private void touch_end(float x, float y) {
STATE = MARKING;
if (touch_counter == 1) {
pointA = new PointF();
pointA.x = ((x - 32.0f)); // + ViewOffset.x));
pointA.y = ((y - 70.0f)); // + ViewOffset.y));
} else if (touch_counter == 2) {
pointB = new PointF();
pointB.x = ((x - 32.0f));
pointB.y = ((y - 70.0f));
if (CURRENT_STATUS == "DRAW_LINE") touch_counter = 0;
Log.i("Image" , "At this Point Calling Draw ");
super.draw(busyCanvas);
}
}
public myImage(Context context , FrameLayout screen) {
super(context);
super.setLayerType(LAYER_TYPE_HARDWARE, null);
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setDither(true);
mPaint.setColor(0xFF0000FF);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(5);
STATE = IMG_INIT;
invalidate();
}
public void freeImage() {
try {
mBitmap.recycle();
tracking.recycle();
} catch (Exception err) {
ImageExceptionHandler(err);
}
}
@Override
public void setImageBitmap(Bitmap bmp) {
try {
STATE = SET_IMAGE;
busyCanvas = new Canvas();
busyCanvas.setBitmap(bmp);
mBitmap = bmp;
busyCanvas.setBitmap(bmp);
} catch (Exception err) {
ImageExceptionHandler(err);
}
super.setImageBitmap(bmp);
}
private void ImageExceptionHandler(Exception err) {
Log.e("image" , "==============================================");
Log.e("image" , "EXCEPTION Handling ");
Log.e("image" , "==============================================");
err.printStackTrace();
}
@Override
public boolean onTouch(View v, MotionEvent event) {
if (CURRENT_STATUS == "PAN & ZOOM" ) ScrollAndZoom(v , event);
else if (CURRENT_STATUS == "OVERLAY" ) OverLay(v , event);
else if (CURRENT_STATUS == "DRAW_LINE" ) AddPoints(v , event);
else {
Log.w("ERROR" , "Should Never Be Here myImage On Touch");
Log.w("ERROR" , "Should Never Be Here myImage On Touch");
}
return true;
}
public void init() {
super.setScaleType( ImageView.ScaleType.MATRIX );
mode = NONE;
matrix = new Matrix();
matrix.set(getImageMatrix());
savematrix = new Matrix();
start = new PointF();
mid = new PointF();
oldDist = 1f;
oldfactor = 1f;
factor = 1f;
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
Log.i("Image" , "Size Changed ["+w+"] x ["+h+"] ["+oldw+"] x ["+oldh+"] ");
super.onSizeChanged(w, h, oldw, oldh);
}
private static final short NONE = 0;
private static final short ZOOM = 1;
private static final short DRAG = 2;
private Matrix matrix = new Matrix();
private Matrix savematrix = new Matrix();
private short mode = NONE;
private PointF start = new PointF();
private PointF mid = new PointF();
private float oldDist = 1f;
private float oldfactor = 1f;
private float factor = 1f;
private void ScrollAndZoom(View view , MotionEvent event) {
STATE = ZOOM_PAN;
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN: start.set(event.getX() , event.getY());
savematrix.set(matrix);
mode = DRAG;
break;
//------------------------------------------------
case MotionEvent.ACTION_POINTER_DOWN: oldDist = spacing(event);
midPoint(mid , event);
mode = ZOOM;
oldfactor = factor;
break;
//------------------------------------------------
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_POINTER_UP: start = new PointF();
mode = NONE;
matrix.set(getImageMatrix());
setBackgroundColor(Color.BLACK);
break;
//------------------------------------------------
case MotionEvent.ACTION_MOVE: matrix.set(savematrix);
if (mode == DRAG) {
float dx = event.getX() - start.x;
float dy = event.getY() - start.y;
setBackgroundColor(Color.BLACK);
matrix.postTranslate(dx, dy);
setImageMatrix(matrix);
} else if (mode == ZOOM) {
float newD = spacing(event);
float newfactor = newD / oldDist;
factor = oldfactor * newfactor;
zoom(newfactor);
}
break;
//------------------------------------------------
}
}
private void zoom (Float scale) {
setBackgroundColor(Color.BLACK);
matrix.postScale(scale , scale , mid.x , mid.y);
setImageMatrix(matrix);
}
private float spacing(MotionEvent event) {
float dx = event.getX(1) - event.getX(0);
float dy = event.getY(1) - event.getY(0);
return FloatMath.sqrt(dx*dx + dy*dy);
}
private void midPoint(PointF point, MotionEvent event) {
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2f , y / 2f);
}
}
Making some progress some steps backwards I have re-written some of it It will now Draw the Line and Zoom the entire image with the line zooming also.
However if I draw a line, then Zoom in Good !
But When I draw again it draws the line a Ultra zooms in, and when you zoom out most of the image is now lost? ? and ideas why?
Thanks in advance
Here is the current code
public class myImage extends ImageView implements OnTouchListener {
private static final short NONE = 0;
private static final short ZOOM = 1;
private static final short DRAG = 2;
private static short mode = NONE;
private static PointF pointA = null;
private static PointF pointB = null;
private ImageView pointer = null;
private PointF busy = new PointF();
private PointF start = new PointF();
private PointF mid = new PointF();
private Matrix matrix = new Matrix();
private Matrix savematrix = new Matrix();
private Bitmap tracking = BitmapFactory.decodeResource(getResources(), R.drawable.target);
private Drawable[] layers = new Drawable[2];
private Bitmap mBitmap;
private Canvas mCanvas;
private Paint mPaint;
private int touch_counter = 0;
private long touchTime = -1;
private float oldDist = 1f;
private float oldfactor = 1f;
private float factor = 1f;
public myImage(Context context , FrameLayout screen) {
super(context);
super.setLayerType(LAYER_TYPE_HARDWARE, null);
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setDither(true);
mPaint.setColor(0xFF0000FF);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(2);
mPaint.setTextSize(20f);
super.setScaleType( ImageView.ScaleType.MATRIX );
mode = NONE;
matrix = new Matrix();
matrix.set(getImageMatrix());
savematrix = new Matrix();
start = new PointF();
mid = new PointF();
oldDist = 1f;
oldfactor = 1f;
factor = 1f;
}
public void freeImage() {
try {
mBitmap.recycle();
tracking.recycle();
} catch (Exception err) {
ImageExceptionHandler(err);
}
}
@Override
public void setImageBitmap(Bitmap bmp) {
try {
mBitmap = bmp;
mCanvas = new Canvas(bmp);
mCanvas.setBitmap(bmp);
} catch (Exception err) {
ImageExceptionHandler(err);
}
super.setImageBitmap(bmp);
}
@Override
public boolean onTouch(View v, MotionEvent event) {
if ( CURRENT_STATUS == "PAN & ZOOM" ) ScrollAndZoom(v , event);
else if ( CURRENT_STATUS == "DRAW_LINE" ) AddPoints(v , event);
else {
Log.w("ERROR" , "Should Never Be Here myImage On Touch");
Log.w("ERROR" , "Should Never Be Here myImage On Touch ["+eedsActivity.CURRENT_STATUS+"] ");
Log.w("ERROR" , "Should Never Be Here myImage On Touch ["+eedsActivity.CURRENT_IMAGE +"] ");
Log.w("ERROR" , "Should Never Be Here myImage On Touch");
}
return true;
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
Log.i("Image" , "Size Changed ["+w+"] x ["+h+"] ["+oldw+"] x ["+oldh+"] ");
super.onSizeChanged(w, h, oldw, oldh);
}
private void myDrawLine(PointF ptA , PointF ptB) {
mCanvas.drawBitmap(mBitmap , matrix , mPaint);
mPaint.setColor(Color.BLUE);
mCanvas.drawLine( ptA.x , ptA.y , ptB.x , ptB.y , mPaint);
if (ptA.x <= ptB.x ) mCanvas.translate( (ptA.x + 0.0f), (ptA.y + 0.0f) );
else mCanvas.translate( (ptA.x + 0.0f), (ptA.y + 0.0f) );
line newLine = new line(ptA , ptB , factor);
switch (newLine.getQuadrant()) {
case 1: mCanvas.rotate( (float) newLine.getAngle() ); break;
case 2: mCanvas.rotate( (newLine.getAngle() - 180.0f) ); break;
case 3: mCanvas.rotate( (newLine.getAngle() + 180.0f) ); break;
case 4: mCanvas.rotate( (float) newLine.getAngle() ); break;
}
String result = "";
mPaint.setColor(Color.YELLOW);
result = String.format("%4.3f mm", newLine.getDistance() );
mCanvas.drawText( result, ((newLine.getDistance() * line.PX_TO_MM) / 3.0f), -6.0f, mPaint);
invalidate();
}
public void recenter() {
oldDist = 1f;
oldfactor = 1f;
factor = 1f;
setBackgroundColor(Color.BLACK);
matrix.setScale(1f, 1f);
matrix.postTranslate(0f , 0f);
setImageMatrix(matrix);
}
private void AddPoints(View view , MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN: touch_start(event.getX() , event.getY()); break;
case MotionEvent.ACTION_MOVE: touch_busy (event.getX() , event.getY()); break;
case MotionEvent.ACTION_UP: touch_end (event.getX() , event.getY()); break;
}
}
private void touch_start(float x, float y) {
touch_counter++;
busy.x = (x - 32.0f);
busy.y = (y - 70.0f);
LayoutParams lp = new LayoutParams(32 , 32);
pointer = new ImageView(super.getContext());
pointer.setBackgroundDrawable(getResources().getDrawable(R.drawable.target2));
lp.leftMargin = (int) x;
lp.topMargin = (int) y;
((ViewGroup) super.getParent()).addView(pointer , lp);
}
private void touch_busy(float x, float y) {
busy.x = (x - 32.0f);
busy.y = (y - 70.0f);
if (pointer != null) {
pointer.setLeft( (int)busy.x ); pointer.setRight ( (int)(busy.x+32) );
pointer.setTop ( (int)busy.y ); pointer.setBottom( (int)(busy.y+32) );
}
}
private void touch_end(float x, float y) {
((ViewGroup) super.getParent()).removeView(pointer);
if (touch_counter == 1) {
pointA = new PointF();
pointA.x = ((x - 32.0f));
pointA.y = ((y - 70.0f));
} else if (touch_counter == 2) {
pointB = new PointF();
pointB.x = ((x - 32.0f));
pointB.y = ((y - 70.0f));
}
if (touch_counter == 2) {
myDrawLine(pointA , pointB);
pointA = null; pointB = null;
pointC = null; touch_counter = 0;
}
}
private void ScrollAndZoom(View view , MotionEvent event) {
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN: if ((System.currentTimeMillis() - touchTime) < 400) {
// Double Click
touchTime = -1;
setBackgroundColor(Color.BLACK);
matrix.setScale(1f, 1f);
matrix.postTranslate(0f , 0f);
setImageMatrix(matrix);
} else {
// Single Click
touchTime = System.currentTimeMillis();
start.set(event.getX() , event.getY());
savematrix.set(matrix);
mode = DRAG;
}
break;
//------------------------------------------------
case MotionEvent.ACTION_POINTER_DOWN: touchTime = -1;
oldDist = distance(event);
midPoint(mid , event);
mode = ZOOM;
oldfactor = factor;
break;
//------------------------------------------------
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_POINTER_UP: start = new PointF();
mode = NONE;
matrix.set(getImageMatrix());
setBackgroundColor(Color.BLACK);
break;
//------------------------------------------------
case MotionEvent.ACTION_MOVE: matrix.set(savematrix);
if (mode == DRAG) {
float dx = event.getX() - start.x;
float dy = event.getY() - start.y;
setBackgroundColor(Color.BLACK);
matrix.postTranslate(dx, dy);
setImageMatrix(matrix);
} else if (mode == ZOOM) {
float newD = distance(event);
float newfactor = newD / oldDist;
factor = oldfactor * newfactor;
setBackgroundColor(Color.BLACK);
matrix.postScale(newfactor , newfactor , mid.x , mid.y);
setImageMatrix(matrix);
}
break;
//------------------------------------------------
}
}
private float distance(MotionEvent event) {
float dx = event.getX(1) - event.getX(0);
float dy = event.getY(1) - event.getY(0);
return FloatMath.sqrt(dx*dx + dy*dy);
}
private void midPoint(PointF point, MotionEvent event) {
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2f , y / 2f);
}
private void ImageExceptionHandler(Exception err) {
Log.e("image" , "==============================================");
Log.e("image" , "EXCEPTION Handling ");
Log.e("image" , "==============================================");
err.printStackTrace();
}
}
Upvotes: 0
Views: 670
Answers (2)
E.Z. Hart
Reputation: 5757
Your line is only drawn when STATE is 'MARKING'; at the end of onDraw you're setting your state back to UNKNOWN which calls the base class's onDraw but doesn't draw your line. If you want your line to stick around in other states, you'll have to redraw it every time onDraw gets called.
Upvotes: 0
Geobits
Reputation: 22342
It looks to me like pointB is always null, because you only ever get one ACTION_DOWN per gesture. When the first finger goes down, you get the action, and it triggers touch_start(), setting touch_counter to 1. When the second finger goes down, it doesn't, because you get an ACTION_POINTER_DOWN instead, which isn't checked for.
That's assuming you want a two-finger gesture. If it's meant to be a 'touch here and then touch there' instead, then you shouldn't set touch_counter to zero with each touch_end().
Upvotes: 1
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