I have a gallery of images with different sizes. Each image is displayed inside an ImageView sequentially (through OnTouchListener). I need to know the position of the frame of the picture I'm showing relatives to the ImageView but with the testing I've done I've only gotten the coordinates of ImageView. Any idea?
I need the values of (x1, y1) and (x2, y2).
Thanks in advance.
This is my class:
public class PuzzleView extends ImageView {
protected Paint currentPaint;
protected boolean drawRect = false;
protected float left;
protected float top;
protected float right;
protected float bottom;
protected float pixelX;
protected float pixelY;
protected int nChunksX = 5;
protected int nChunksY = 5;
protected int currentWidth = 0;
protected int currentHeight = 0;
public PuzzleView(Context context, AttributeSet attrs) {
super(context, attrs);
currentPaint = new Paint();
currentPaint.setDither(true);
currentPaint.setColor(0xFF00CC00);
currentPaint.setStyle(Paint.Style.STROKE);
currentPaint.setStrokeJoin(Paint.Join.ROUND);
currentPaint.setStrokeCap(Paint.Cap.ROUND);
currentPaint.setStrokeWidth(2);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
float chunkWidth = currentWidth / nChunksX;
float chunkHeight = currentHeight / nChunksY;
float posX = ((int)(pixelX / chunkWidth)) * chunkWidth;
float posY = ((int)(pixelY / chunkHeight)) * chunkHeight;
canvas.drawRect(posX, posY, posX + chunkWidth, posY + chunkHeight, currentPaint);
Rect rect = this.getDrawable().getBounds();
canvas.drawRect(rect, currentPaint);
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
// Get image matrix values and place them in an array
float[] f = new float[9];
getImageMatrix().getValues(f);
// Extract the scale values using the constants (if aspect ratio maintained, scaleX == scaleY)
final float scaleX = f[Matrix.MSCALE_X];
final float scaleY = f[Matrix.MSCALE_Y];
// Get the drawable (could also get the bitmap behind the drawable and getWidth/getHeight)
final Drawable d = getDrawable();
final int origW = d.getIntrinsicWidth();
final int origH = d.getIntrinsicHeight();
// Calculate the actual dimensions
final int actW = Math.round(origW * scaleX);
final int actH = Math.round(origH * scaleY);
currentWidth = actW;
currentHeight = actH;
}
public boolean isDrawRect() {
return drawRect;
}
public void setDrawRect(boolean drawRect) {
this.drawRect = drawRect;
}
public float getLeftRect() {
return left;
}
public void setLeftRect(float left) {
this.left = left;
}
public float getTopRect() {
return top;
}
public void setTopRect(float top) {
this.top = top;
}
public float getRightRect() {
return right;
}
public void setRightRect(float right) {
this.right = right;
}
public float getBottomRect() {
return bottom;
}
public void setBottomRect(float bottom) {
this.bottom = bottom;
}
public float getPixelX() {
return pixelX;
}
public void setPixelX(float pixelX) {
this.pixelX = pixelX;
}
public float getPixelY() {
return pixelY;
}
public void setPixelY(float pixelY) {
this.pixelY = pixelY;
}
public int getChunksX() {
return nChunksX;
}
public void setChunksX(int nChunksX) {
this.nChunksX = nChunksX;
}
public int getChunksY() {
return nChunksY;
}
public void setChunksY(int nChunksY) {
this.nChunksY = nChunksY;
}
}
For now, the source image is defined in XML file:
<com.jocajica.shakepic.PuzzleView
android:id="#+id/imageViewSelected"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:contentDescription="#string/image_selected"
android:src="#android:drawable/progress_indeterminate_horizontal" />
I need to draw a grid over the image.
According to Jacob Nordfalk's link, I was able to produce a static method allowing you to get the image position and dimensions from an ImageView.
/**
* Returns the bitmap position inside an imageView.
* #param imageView source ImageView
* #return 0: left, 1: top, 2: width, 3: height
*/
public static int[] getBitmapPositionInsideImageView(ImageView imageView) {
int[] ret = new int[4];
if (imageView == null || imageView.getDrawable() == null)
return ret;
// Get image dimensions
// Get image matrix values and place them in an array
float[] f = new float[9];
imageView.getImageMatrix().getValues(f);
// Extract the scale values using the constants (if aspect ratio maintained, scaleX == scaleY)
final float scaleX = f[Matrix.MSCALE_X];
final float scaleY = f[Matrix.MSCALE_Y];
// Get the drawable (could also get the bitmap behind the drawable and getWidth/getHeight)
final Drawable d = imageView.getDrawable();
final int origW = d.getIntrinsicWidth();
final int origH = d.getIntrinsicHeight();
// Calculate the actual dimensions
final int actW = Math.round(origW * scaleX);
final int actH = Math.round(origH * scaleY);
ret[2] = actW;
ret[3] = actH;
// Get image position
// We assume that the image is centered into ImageView
int imgViewW = imageView.getWidth();
int imgViewH = imageView.getHeight();
int top = (int) (imgViewH - actH)/2;
int left = (int) (imgViewW - actW)/2;
ret[0] = left;
ret[1] = top;
return ret;
}
You should use getImageMatrix():
float[] imageMatrix = new float[9];
getImageMatrix().getValues(imageMatrix);
scale = imageMatrix[Matrix.MSCALE_X];
transX = imageMatrix[Matrix.MTRANS_X];
See also
Trying to get the display size of an image in an ImageView
Thank you Quentis S. and Jacob Nordfalk for the very usefull routine.
I took the liberty of changing the return value from an array to a Rect object.
/**
* Returns the bitmap position inside an imageView.
*
* #param imageView source ImageView
* #return Rect position of the bitmap in the ImageView
*/
public static final Rect getBitmapPositionInsideImageView(ImageView imageView)
{
Rect rect = new Rect();
if (imageView == null || imageView.getDrawable() == null)
{
return rect;
}
// Get image dimensions
// Get image matrix values and place them in an array
float[] f = new float[9];
imageView.getImageMatrix().getValues(f);
// Extract the scale values using the constants (if aspect ratio maintained, scaleX == scaleY)
final float scaleX = f[Matrix.MSCALE_X];
final float scaleY = f[Matrix.MSCALE_Y];
// Get the drawable (could also get the bitmap behind the drawable and getWidth/getHeight)
final Drawable d = imageView.getDrawable();
final int origW = d.getIntrinsicWidth();
final int origH = d.getIntrinsicHeight();
// Calculate the actual dimensions
final int actW = Math.round(origW * scaleX);
final int actH = Math.round(origH * scaleY);
// Get image position
// We assume that the image is centered into ImageView
int imgViewW = imageView.getWidth();
int imgViewH = imageView.getHeight();
rect.top = (int) (imgViewH - actH) / 2;
rect.left = (int) (imgViewW - actW) / 2;
rect.bottom = rect.top + actH;
rect.right = rect.left + actW;
return rect;
}
Override the onLayout method
//inside puzzleView
float[] matrix = new float[9];
#Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
matrix = getMatrix();
}
public void getMatrix(){
return matrix;
}
private float[] getMatrix() {
final float[] matrix = new float[9];
getImageMatrix().getValues(matrix);
return matrix;
}
and use this to get values
// Extract the scale and translation values from the matrix.
float scaleX = matrix[Matrix.MSCALE_X];
float scaleY = matrix[Matrix.MSCALE_Y];
float transX = matrix[Matrix.MTRANS_X];
float transY = matrix[Matrix.MTRANS_Y];
I hope that this help u
Related
This code is working, I created Scratch image view through which I can scratch the image view to see the the image, but scratch image view is automatically filling with scratch pattern when I reopen the app or I move to previous activity.only once the user should scratch the image view to view image and it should not fill again when I reopen the app or move to previous activity .Can anyone help me
<com.example.swapnanadendla.scratch.ScratchImageView
android:id="#+id/sample_image"
android:layout_width="200dp"
android:layout_height="200dp"
android:layout_gravity="center"
android:layout_marginTop="20dp"
android:background="#android:color/white"
android:src="#drawable/image" />
.
public class ScratchImageView extends ImageView{
public interface IRevealListener {
void onRevealed(ScratchImageView iv);
void onRevealPercentChangedListener(ScratchImageView siv, float percent);
}
public static final float STROKE_WIDTH = 12f;
private float mX, mY;
private static final float TOUCH_TOLERANCE = 4;
/**
* Bitmap holding the scratch region.
*/
private Bitmap mScratchBitmap;
/**
* Drawable canvas area through which the scratchable area is drawn.
*/
private Canvas mCanvas;
/**
* Path holding the erasing path done by the user.
*/
private Path mErasePath;
/**
* Path to indicate where the user have touched.
*/
private Path mTouchPath;
/**
* Paint properties for drawing the scratch area.
*/
private Paint mBitmapPaint;
/**
* Paint properties for erasing the scratch region.
*/
private Paint mErasePaint;
/**
* Gradient paint properties that lies as a background for scratch region.
*/
private Paint mGradientBgPaint;
/**
* Sample Drawable bitmap having the scratch pattern.
*/
private BitmapDrawable mDrawable;
/**
* Listener object callback reference to send back the callback when the image has been revealed.
*/
private IRevealListener mRevealListener;
/**
* Reveal percent value.
*/
private float mRevealPercent;
/**
* Thread Count
*/
private int mThreadCount = 0;
public ScratchImageView(Context context) {
super(context);
init();
}
public ScratchImageView(Context context, AttributeSet set) {
super(context, set);
init();
}
public ScratchImageView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
/**
* Set the strokes width based on the parameter multiplier.
* #param multiplier can be 1,2,3 and so on to set the stroke width of the paint.
*/
public void setStrokeWidth(int multiplier) {
mErasePaint.setStrokeWidth(multiplier * STROKE_WIDTH);
}
/**
* Initialises the paint drawing elements.
*/
private void init() {
mTouchPath = new Path();
mErasePaint = new Paint();
mErasePaint.setAntiAlias(true);
mErasePaint.setDither(true);
mErasePaint.setColor(0xFFFF0000);
mErasePaint.setStyle(Paint.Style.STROKE);
mErasePaint.setStrokeJoin(Paint.Join.BEVEL);
mErasePaint.setStrokeCap(Paint.Cap.ROUND);
setStrokeWidth(6);
mGradientBgPaint = new Paint();
mErasePath = new Path();
mBitmapPaint = new Paint(Paint.DITHER_FLAG);
Bitmap scratchBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.ic_scratch_pattern);
mDrawable = new BitmapDrawable(getResources(), scratchBitmap);
mDrawable.setTileModeXY(Shader.TileMode.REPEAT, Shader.TileMode.REPEAT);
setEraserMode();
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
mScratchBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
mCanvas = new Canvas(mScratchBitmap);
Rect rect = new Rect(0, 0, mScratchBitmap.getWidth(), mScratchBitmap.getHeight());
mDrawable.setBounds(rect);
int startGradientColor = ContextCompat.getColor(getContext(), R.color.scratch_start_gradient);
int endGradientColor = ContextCompat.getColor(getContext(), R.color.scratch_end_gradient);
mGradientBgPaint.setShader(new LinearGradient(0, 0, 0, getHeight(), startGradientColor, endGradientColor, Shader.TileMode.MIRROR));
mCanvas.drawRect(rect, mGradientBgPaint);
mDrawable.draw(mCanvas);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawBitmap(mScratchBitmap, 0, 0, mBitmapPaint);
canvas.drawPath(mErasePath, mErasePaint);
}
private void touch_start(float x, float y) {
mErasePath.reset();
mErasePath.moveTo(x, y);
mX = x;
mY = y;
}
/**
* clears the scratch area to reveal the hidden image.
*/
public void clear() {
int[] bounds = getImageBounds();
int left = bounds[0];
int top = bounds[1];
int right = bounds[2];
int bottom = bounds[3];
int width = right - left;
int height = bottom - top;
int centerX = left + width / 2;
int centerY = top + height / 2;
left = centerX - width / 2;
top = centerY - height / 2;
right = left + width;
bottom = top + height;
Paint paint = new Paint();
paint.setXfermode(new PorterDuffXfermode(
PorterDuff.Mode.CLEAR));
mCanvas.drawRect(left, top, right, bottom, paint);
checkRevealed();
invalidate();
}
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) {
mErasePath.quadTo(mX, mY, (x + mX) / 2, (y + mY) / 2);
mX = x;
mY = y;
drawPath();
}
mTouchPath.reset();
mTouchPath.addCircle(mX, mY, 30, Path.Direction.CW);
}
private void drawPath() {
mErasePath.lineTo(mX, mY);
// commit the path to our offscreen
mCanvas.drawPath(mErasePath, mErasePaint);
// kill this so we don't double draw
mTouchPath.reset();
mErasePath.reset();
mErasePath.moveTo(mX, mY);
checkRevealed();
//reveal();
}
public void reveal() {
clear();
}
private void touch_up() {
drawPath();
}
#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;
default:
break;
}
return true;
}
public int getColor() {
return mErasePaint.getColor();
}
public Paint getErasePaint() {
return mErasePaint;
}
public void setEraserMode() {
getErasePaint().setXfermode(new PorterDuffXfermode(
PorterDuff.Mode.CLEAR));
}
public void setRevealListener(IRevealListener listener) {
this.mRevealListener = listener;
}
public boolean isRevealed() {
return mRevealPercent == 1;
}
private void checkRevealed() {
if(! isRevealed() && mRevealListener != null) {
int[] bounds = getImageBounds();
int left = bounds[0];
int top = bounds[1];
int width = bounds[2] - left;
int height = bounds[3] - top;
// Do not create multiple calls to compare.
if(mThreadCount > 1) {
Log.d("Captcha", "Count greater than 1");
return;
}
mThreadCount++;
// new AsyncTask<Integer, Void, Float>() {
//
// #Override
// protected Float doInBackground(Integer... params) {
//
// try {
// int left = params[0];
// int top = params[1];
// int width = params[2];
// int height = params[3];
//
// Bitmap croppedBitmap = Bitmap.createBitmap(mScratchBitmap, left, top, width, height);
//
// return BitmapUtils.getTransparentPixelPercent(croppedBitmap);
// } finally {
// mThreadCount--;
// }
// }
//
// public void onPostExecute(Float percentRevealed) {
//
// // check if not revealed before.
// if( ! isRevealed()) {
//
// float oldValue = mRevealPercent;
// mRevealPercent = percentRevealed;
//
// if(oldValue != percentRevealed) {
// mRevealListener.onRevealPercentChangedListener(ScratchImageView.this, percentRevealed);
// }
//
// // if now revealed.
// if( isRevealed()) {
// mRevealListener.onRevealed(ScratchImageView.this);
// }
// }
// }
//
// }.execute(left, top, width, height);
}
}
public int[] getImageBounds() {
int paddingLeft = getPaddingLeft();
int paddingTop = getPaddingTop();
int paddingRight = getPaddingRight();
int paddingBottom = getPaddingBottom();
int vwidth = getWidth() - paddingLeft - paddingRight;
int vheight = getHeight() - paddingBottom - paddingTop;
int centerX = vwidth/2;
int centerY = vheight/2;
Drawable drawable = getDrawable();
Rect bounds = drawable.getBounds();
int width = drawable.getIntrinsicWidth();
int height = drawable.getIntrinsicHeight();
if(width <= 0) {
width = bounds.right - bounds.left;
}
if(height <= 0) {
height = bounds.bottom - bounds.top;
}
int left;
int top;
if(height > vheight) {
height = vheight;
}
if(width > vwidth) {
width = vwidth;
}
ScaleType scaleType = getScaleType();
switch (scaleType) {
case FIT_START:
left = paddingLeft;
top = centerY - height / 2;
break;
case FIT_END:
left = vwidth - paddingRight - width;
top = centerY - height / 2;
break;
case CENTER:
left = centerX - width / 2;
top = centerY - height / 2;
break;
default:
left = paddingLeft;
top = paddingTop;
width = vwidth;
height = vheight;
break;
}
return new int[] {left, top, left + width, top + height};
}
}
What you can do is store into Firebase a variable like isScratched = 1 or 0, if it's 1 it's because the user didn't scratch it yet. If the user scratch it that variable will be 0 and then in onStart you put a listener of Firebase database, if the listener finds out the value is 0 the scratch card will not be available.
I will show you some snippet here
private DatabaseReference mDatabase; //First declare your database reference
Then in init() or onCreate()
mDatabase = FirebaseDatabase.getInstance().getReference();
mDatabase.child("isScratched").setValue("1"); //here we create the isScratched and set it to 1 , meaning that the photo is not even scratched yet
Now, after the photo is scratched just set that value to 0
//After your scratch method or when the user finishes scratching the pick
mDatabase.child("isScratched").setValue("0");
Now in your onStart() or in the Activity where the image appears just attach a listener
mDatabase.child("isScratched").addSingleValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
String getScratchedValue = datasnapshot.getValue(String.class);
Log.e("IsScratched : " ,""+getScratchedValue);
if(getScratchedValue.equals(0)){
//Your picture is already scratched, run the method that will show it scratched
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
System.out.println("Database Error: "+databaseError.getDetails());
}
});
I am trying to implement Oval path animation, I want to show path animation using image, I tried https://github.com/matthewrkula/AnimatedPathView but it's not work for oval. I also tried below code for oval path but it is shows circle, Anyone have an idea? Thanks in advance!!!
MyAnimation.java
public class MyAnimation extends Animation {
private View view;
private float cx, cy; // center x,y position of circular path
private float prevX, prevY; // previous x,y position of image during animation
private float r; // radius of circle
private float prevDx, prevDy;
/**
* #param view - View that will be animated
* #param r - radius of circular path
*/
public MyAnimation(View view, float r){
this.view = view;
this.r = r;
}
#Override
public boolean willChangeBounds() {
return true;
}
#Override
public void initialize(int width, int height, int parentWidth, int parentHeight) {
// calculate position of image center
int cxImage = width / 2;
int cyImage = height / 1;
cx = view.getLeft() + cxImage;
cy = view.getTop() + cyImage;
// set previous position to center
prevX = cx;
prevY = cy;
}
#Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
if(interpolatedTime == 0){
t.getMatrix().setTranslate(prevDx, prevDy);
return;
}
float angleDeg = (interpolatedTime * 360f + 90) % 360;
float angleRad = (float) Math.toRadians(angleDeg);
// r = radius, cx and cy = center point, a = angle (radians)
float x = (float) (cx + r * Math.cos(angleRad));
float y = (float) (cy + r * Math.sin(angleRad));
float dx = prevX - x;
float dy = prevY - y;
prevX = x;
prevY = y;
prevDx = dx;
prevDy = dy;
t.getMatrix().setTranslate(dx, dy);
}
}
PathAnimation.java
image = (ImageView) findViewById(R.id.image);
image.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Animation anim = new MyAnimation(image, 300);
anim.setDuration(1000);
image.startAnimation(anim);
}
});
I have found the solution after many tried using this custom class
AnimationView.java
public class AnimationView extends View {
Paint paint;
long animationDuration = 10000;
int framesPerSecond = 60;
Bitmap bm;
int bm_offsetX, bm_offsetY;
Path animPath;
PathMeasure pathMeasure;
float pathLength;
float step; //distance each step
float distance; //distance moved
float[] pos;
float[] tan;
Matrix matrix;
public AnimationView(Context context) {
super(context);
initMyView();
}
public AnimationView(Context context, AttributeSet attrs) {
super(context, attrs);
initMyView();
}
public AnimationView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
initMyView();
}
#TargetApi(Build.VERSION_CODES.LOLLIPOP)
public void initMyView(){
paint = new Paint();
paint.setColor(Color.RED);
paint.setStrokeWidth(5);
paint.setStyle(Paint.Style.STROKE);
bm = BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher);
bm_offsetX = bm.getWidth()/2;
bm_offsetY = bm.getHeight()/2;
animPath = new Path();
animPath.moveTo(100, 100);
animPath.addArc(new RectF(1, 100, 300, 600), 1, 800);
animPath.close();
pathMeasure = new PathMeasure(animPath, false);
pathLength = pathMeasure.getLength();
Toast.makeText(getContext(), "pathLength: " + pathLength, Toast.LENGTH_LONG).show();
step = 1;
distance = 0;
pos = new float[2];
tan = new float[2];
matrix = new Matrix();
}
#Override
protected void onDraw(Canvas canvas) {
canvas.drawPath(animPath, paint);
if(distance < pathLength){
pathMeasure.getPosTan(distance, pos, tan);
matrix.reset();
float degrees = (float)(Math.atan2(tan[1], tan[0])*180.0/Math.PI);
matrix.postRotate(degrees, bm_offsetX, bm_offsetY);
matrix.postTranslate(pos[0]-bm_offsetX, pos[1]-bm_offsetY);
canvas.drawBitmap(bm, matrix, null);
distance += step;
}else{
distance = 0;
}
invalidate();
}
}
and put into xml
<com.example.android.mydemo.animation.pathanimation.AnimationView
android:layout_width="match_parent"
android:layout_height="450dp" />
I have a custom view that I want to use to display the amplitude of audio coming in through the microphone in a line graph.
Getting the amplitude and all that I have no problem with, and drawing the lines is not really a problem either.
What I want to do is show the amplitude starting at the far right edge, moving left. So with each new sample I want to translate the bitmap to the left, then draw a line from the last point to the new point. I'm not sure what the easiest way to achieve this is. I originally was able to do it by drawing Paths and just adding a new point to the path with each sample, the problem was that after like a minute the path was too big to be drawn. So I thought about it and wanted to switch to using a cached bitmap, translate that on each iteration, and draw from the last point to the new point. However this is tricky to do as (after experimentation). When I translate the bitmap it doesn't move the far left pixels off the bitmap, it just moves the entire bitmap in the canvas and I have no way to write pixels to the right side.
Below is a description of what I'm trying to do:
Given this:
I want to translate that to the left:
Then draw a line to a new point the space space on the right
Of course, step 2 and 3 should happen at essentially the same time.
How can I achieve this? I'm open to new ideas altogether, like perhaps saving all the points for up to 1 screen worth and drawing them out on each onDraw call. I'd prefer to just save them in a bitmap and do some kind of translation/clipping etc to achieve the same thing with perhaps less overhead.
private static final int MAX_AMPLITUDE = 32767;
float lx, ly;
private Paint mPaint;
private Bitmap mBitmap;
private Canvas mCanvas;
private void init() {
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeWidth(5);
mPaint.setColor(Color.Black);
}
#Override
public void onSizeChanged(int w, int h, int oldw, int oldh) {
if (mBitmap != null) {
mBitmap.recycle();
}
mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
mCanvas = new Canvas(mBitmap);
height = h;
width = w;
ly = height;
lx = width;
amplitudeDivisor = ((float) MAX_AMPLITUDE / (float) height);
}
#Override
public void onDraw(Canvas canvas) {
mAmplitude = (float)(MAX_AMPLITUDE * Math.random());
float dx = width - delta;
float dy = height - (mAmplitude / amplitudeDivisor);
mCanvas.drawLine(lx, ly, dx, dy, mPaint);
mCanvas.translate(-delta, 0);
canvas.drawBitmap(mBitmap, 0, 0, mPaint);
lx = dx;
ly = dy;
delta+=10;
postInvalidateDelayed(200);
}
The above is just a sample, I'm just using a random value for the amplitude to simplify for now. I've tried a bunch of things with no luck. Any help would be greatly appreciated.
I ended up getting this working by saving the points to an array. I draw a white line before the recording starts. Note that I use an EvictingQueue from the Guava library as a circular buffer of points to render on a line. To use this, once a recording starts call start() and when it ends call stop. From your activity you will need to send MediaRecorder getMaxAmplitude() values to the updateAmplitude() method of this class, and do so at an interval of say 50 ms. The view also supports rotation.
public class AmplitudeWaveFormView extends View {
private static final String TAG = AmplitudeWaveFormView.class.getSimpleName();
private static final int MAX_AMPLITUDE = 32767;
private static final int SAMPLES_PER_SCREEN = 100;
private float mAmplitude = 0;
private Paint mRecordingPaint, mNotRecordingPaint;
private int height = -1;
private int width = -1;
private boolean mIsStarted;
private float[] lastPoints;
private int oldWidth = -1, oldHeight = -1;
private int mCurrentSample;
private float amplitudeDivisor = 1;
private float lx,ly, deltaX;
private EvictingQueue<Float> mPointQueue;
private int recordColor;
private int notRecordingColor;
public AmplitudeWaveFormView(Context context) {
super(context);
init();
}
public AmplitudeWaveFormView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public AmplitudeWaveFormView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
public void start() {
mIsStarted = true;
}
public void stop() {
mIsStarted = false;
}
public void updateAmplitude(float amplitude) {
mAmplitude = amplitude;
postInvalidate();
}
private void init() {
recordColor = getResources().getColor(R.color.mint);
notRecordingColor = getResources().getColor(R.color.alpine);
mRecordingPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mRecordingPaint.setStyle(Paint.Style.STROKE);
mRecordingPaint.setStrokeWidth(5);
mRecordingPaint.setColor(recordColor);
mNotRecordingPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mNotRecordingPaint.setStyle(Paint.Style.STROKE);
mNotRecordingPaint.setStrokeWidth(5);
mNotRecordingPaint.setColor(notRecordingColor);
}
#Override
public void onSizeChanged(int w, int h, int oldw, int oldh) {
height = h;
width = w;
ly = height;
lx = width;
deltaX = (float)width / (float)SAMPLES_PER_SCREEN;
amplitudeDivisor = ((float) MAX_AMPLITUDE / (float) height);
mPointQueue = EvictingQueue.create(SAMPLES_PER_SCREEN * 4);
if (lastPoints != null && lastPoints.length > 0) {
float xScale = (float) width/oldWidth;
float yScale = (float) height/oldHeight;
Matrix matrix = new Matrix();
matrix.setScale(xScale, yScale);
matrix.mapPoints(lastPoints);
mPointQueue.addAll(Floats.asList(lastPoints));
ly = lastPoints[lastPoints.length-1];
lx= lastPoints[lastPoints.length -2];
lastPoints = null;
}
}
#Override
public void onRestoreInstanceState(Parcelable state) {
if (state instanceof Bundle) {
Bundle bundle = (Bundle) state;
mCurrentSample = bundle.getInt("sample");
lastPoints = bundle.getFloatArray("lines");
oldWidth = bundle.getInt("oldWidth");
oldHeight = bundle.getInt("oldHeight");
state = ((Bundle) state).getParcelable("parent");
}
super.onRestoreInstanceState(state);
}
#Override
public Parcelable onSaveInstanceState() {
Bundle bundle = new Bundle();
bundle.putFloatArray("lines", Floats.toArray(mPointQueue));
bundle.putInt("sample", mCurrentSample);
bundle.putParcelable("parent", super.onSaveInstanceState());
bundle.putInt("oldWidth", width);
bundle.putInt("oldHeight", height);
return bundle;
}
#Override
public void onDraw(Canvas canvas) {
if (mIsStarted) {
float x = lx + deltaX;
float y = height - (mAmplitude / amplitudeDivisor);
mPointQueue.add(lx);
mPointQueue.add(ly);
mPointQueue.add(x);
mPointQueue.add(y);
lastPoints = Floats.toArray(mPointQueue);
lx = x;
ly = y;
}
if (lastPoints != null && lastPoints.length > 0) {
int len = mPointQueue.size() / 4 >= SAMPLES_PER_SCREEN ? SAMPLES_PER_SCREEN * 4 : mPointQueue.size();
float translateX = width - lastPoints[lastPoints.length - 2];
canvas.translate(translateX, 0);
canvas.drawLines(lastPoints, 0, len, mRecordingPaint);
}
if (mCurrentSample <= SAMPLES_PER_SCREEN) {
drawNotRecordingLine(canvas);
}
mCurrentSample++;
}
private void drawNotRecordingLine(Canvas canvas) {
canvas.drawLine(0,height, width, height, mNotRecordingPaint);
}
}
I would like my ImageView to scale in a particular fashion:
Scale so that the height of the image always fits the height of the ImageView
Crop any excess width
A picture speaks louder than a 1000 words, so here is a representation of how I want my ImageView to behave. Suppose it has a fixed height of say 100dp and suppose its width is match_parent.
Note that
on the phone layout, the image height is stretched, but the sides are cropped, akin to CROP_CENTER.
on the tablet layout, the image is also stretched to fit the ImageView height, behaving like FIT_CENTER
I suspect I need scaleType:matrix, but after that I'm lost. How can I make sure an image fits Y, but crops X?
In xml, use:
android:scaleType="centerCrop"
android:adjustViewBounds="true"
from & thanks to: https://stackoverflow.com/a/15600295/2162226
With a little help from my friends Carlos Robles and pskink, came up with the following custom ImageView:
public class FitYCropXImageView extends ImageView {
boolean done = false;
#SuppressWarnings("UnusedDeclaration")
public FitYCropXImageView(Context context) {
super(context);
setScaleType(ScaleType.MATRIX);
}
#SuppressWarnings("UnusedDeclaration")
public FitYCropXImageView(Context context, AttributeSet attrs) {
super(context, attrs);
setScaleType(ScaleType.MATRIX);
}
#SuppressWarnings("UnusedDeclaration")
public FitYCropXImageView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
setScaleType(ScaleType.MATRIX);
}
private final RectF drawableRect = new RectF(0, 0, 0,0);
private final RectF viewRect = new RectF(0, 0, 0,0);
private final Matrix m = new Matrix();
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
if (done) {
return;//Already fixed drawable scale
}
final Drawable d = getDrawable();
if (d == null) {
return;//No drawable to correct for
}
int viewHeight = getMeasuredHeight();
int viewWidth = getMeasuredWidth();
int drawableWidth = d.getIntrinsicWidth();
int drawableHeight = d.getIntrinsicHeight();
drawableRect.set(0, 0, drawableWidth, drawableHeight);//Represents the original image
//Compute the left and right bounds for the scaled image
float viewHalfWidth = viewWidth / 2;
float scale = (float) viewHeight / (float) drawableHeight;
float scaledWidth = drawableWidth * scale;
float scaledHalfWidth = scaledWidth / 2;
viewRect.set(viewHalfWidth - scaledHalfWidth, 0, viewHalfWidth + scaledHalfWidth, viewHeight);
m.setRectToRect(drawableRect, viewRect, Matrix.ScaleToFit.CENTER /* This constant doesn't matter? */);
setImageMatrix(m);
done = true;
requestLayout();
}
}
If you use scaleType:matrix you will need to create your own Matrix and asign it to the view by means of setImageMatrix(Matrix) or manually modify the matrix at hen onMEasure method of a customImageView.
public class MyImageView extends ImageView {
boolean done=false;
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
if (done)
return;
final Drawable d = getDrawable();
final int drawableW = d.getIntrinsicWidth();
final int drawableH = d.getIntrinsicHeight();
float ratio = drawableW / drawableH;
//int width = getMeasuredWidth();
int height = getMeasuredHeight();
float scale=height/drawableH;
Matrix m = getImageMatrix();
float[] f = new float[9];
m.getValues(f);
f[Matrix.MSCALE_X]=scale;
f[Matrix.MSCALE_Y]=scale;
m.setValues(f);
done = true;
requestLayout();
}
}
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
LayoutParams params;
final ImageView iv0 = new ImageView(this);
//iv0.setBackgroundColor(0xffff0000);
params = new LayoutParams(LayoutParams.MATCH_PARENT, 100);
ll.addView(iv0, params);
final ImageView iv1 = new ImageView(this);
//iv1.setBackgroundColor(0xff00ff00);
params = new LayoutParams(60, 100);
ll.addView(iv1, params);
setContentView(ll);
Runnable action = new Runnable() {
#Override
public void run() {
Drawable d = getResources().getDrawable(R.drawable.layer0);
int dw = d.getIntrinsicWidth();
int dh = d.getIntrinsicHeight();
RectF src = new RectF(0, 0, dw, dh);
ImageView[] iviews = {iv0, iv1};
for (int i = 0; i < iviews.length; i++) {
ImageView iv = iviews[i];
iv.setImageDrawable(d);
iv.setScaleType(ScaleType.MATRIX);
float h = iv.getHeight();
float w = iv.getWidth();
float cx = w / 2;
float scale = h / dh;
float deltaw = dw * scale / 2;
RectF dst = new RectF(cx - deltaw, 0, cx + deltaw, h);
Matrix m = new Matrix();
m.setRectToRect(src, dst, ScaleToFit.FILL);
iv.setImageMatrix(m);
}
}
};
iv1.post(action);
If you want to display the center of the image, use:
android:scaleType="centerCrop"
android:adjustViewBounds="true"
If you want to show the edge of the image instead of the center, use:
android:scaleType="matrix"
android:adjustViewBounds="true"
I am trying to get the height and width of the Image after zoom in and Zoom Out . Is there any way to get height and width in Android after zoom effects. I tried a lot but getting the actual height and width of the image.
public class ImageZoomView extends View implements Observer {
/** Paint object used when drawing bitmap. */
private final Paint mPaint = new Paint(Paint.FILTER_BITMAP_FLAG);
/** Rectangle used (and re-used) for cropping source image. */
private final Rect mRectSrc = new Rect();
/** Rectangle used (and re-used) for specifying drawing area on canvas. */
private final Rect mRectDst = new Rect();
/** The bitmap that we're zooming in, and drawing on the screen. */
private Bitmap mBitmap;
/** Pre-calculated aspect quotient. */
private float mAspectQuotient;
/** State of the zoom. */
private ZoomState mState;
// Public methods
/**
* Constructor
*/
public ImageZoomView(Context context, AttributeSet attrs) {
super(context, attrs);
}
/**
* Set image bitmap
*
* #param bitmap The bitmap to view and zoom into
*/
public void setImage(Bitmap bitmap) {
mBitmap = bitmap;
calculateAspectQuotient();
invalidate();
}
/**
* Set object holding the zoom state that should be used
*
* #param state The zoom state
*/
public void setZoomState(ZoomState state) {
if (mState != null) {
mState.deleteObserver(this);
}
mState = state;
mState.addObserver(this);
invalidate();
}
// Private methods
private void calculateAspectQuotient() {
if (mBitmap != null) {
mAspectQuotient = (((float)mBitmap.getWidth()) / mBitmap.getHeight())
/ (((float)getWidth()) / getHeight());
}
}
// Superclass overrides
#Override
protected void onDraw(Canvas canvas) {
if (mBitmap != null && mState != null) {
final int viewWidth = getWidth();
final int viewHeight = getHeight();
final int bitmapWidth = mBitmap.getWidth();
final int bitmapHeight = mBitmap.getHeight();
final float panX = mState.getPanX();
final float panY = mState.getPanY();
final float zoomX = mState.getZoomX(mAspectQuotient) * viewWidth / bitmapWidth;
final float zoomY = mState.getZoomY(mAspectQuotient) * viewHeight / bitmapHeight;
Log.i("onDraw", "onDraw"+SimpleSeekBarListener.f);
// Setup source and destination rectangles
mRectSrc.left = (int)(panX * bitmapWidth - viewWidth / (zoomX * 2));
mRectSrc.top = (int)(panY * bitmapHeight - viewHeight / (zoomY * 2));
mRectSrc.right = (int)(mRectSrc.left + viewWidth / zoomX);
mRectSrc.bottom = (int)(mRectSrc.top + viewHeight / zoomY);
mRectDst.left = getLeft();
mRectDst.top = getTop();
mRectDst.right = getRight();
mRectDst.bottom = getBottom();
// Adjust source rectangle so that it fits within the source image.
if (mRectSrc.left < 0) {
mRectDst.left += -mRectSrc.left * zoomX;
mRectSrc.left = 0;
}
if (mRectSrc.right > bitmapWidth) {
mRectDst.right -= (mRectSrc.right - bitmapWidth) * zoomX;
mRectSrc.right = bitmapWidth;
}
if (mRectSrc.top < 0) {
mRectDst.top += -mRectSrc.top * zoomY;
mRectSrc.top = 0;
}
if (mRectSrc.bottom > bitmapHeight) {
mRectDst.bottom -= (mRectSrc.bottom - bitmapHeight) * zoomY;
mRectSrc.bottom = bitmapHeight;
}
canvas.drawBitmap(mBitmap, mRectSrc, mRectDst, mPaint);
double i1=bitmapHeight*mAspectQuotient;
double i2=bitmapWidth*mAspectQuotient;
Log.v("Image Height",i1+"");
Log.i("Image Width",i2+"");
Paint paint = new Paint();
paint.setColor(Color.GREEN);
paint.setStrokeWidth(3);
canvas.drawRect(40,40, 80*SimpleSeekBarListener.f, 80*SimpleSeekBarListener.f, paint);
}
}
#Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
calculateAspectQuotient();
}
// implements Observer
public void update(Observable observable, Object data) {
invalidate();
}
}