Goku :
How can i implement freehand cropping on Imageview.
Using below code i'm able to draw freehand path and can able to crop image but i'm facing some other problems
Now what i have tried so far
Here is my code
code for cropping image using canvas
public class SomeView extends View implements View.OnTouchListener {
private Paint paint;
int DIST = 2;
boolean flgPathDraw = true;
Point mfirstpoint = null;
boolean bfirstpoint = false;
Point mlastpoint = null;
Bitmap bitmap;
Context mContext;
public SomeView(Context c, Bitmap bitmap) {
super(c);
mContext = c;
this.bitmap = bitmap;
setFocusable(true);
setFocusableInTouchMode(true);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setPathEffect(new DashPathEffect(new float[]{10, 20}, 0));
paint.setStrokeWidth(5);
paint.setColor(Color.RED);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeCap(Paint.Cap.ROUND);
this.setOnTouchListener(this);
points = new ArrayList<Point>();
bfirstpoint = false;
}
public SomeView(Context context, AttributeSet attrs) {
super(context, attrs);
mContext = context;
setFocusable(true);
setFocusableInTouchMode(true);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5);
paint.setColor(Color.RED);
points = new ArrayList<Point>();
bfirstpoint = false;
this.setOnTouchListener(this);
}
public void onDraw(Canvas canvas) {
/*Rect dest = new Rect(0, 0, getWidth(), getHeight());
paint.setFilterBitmap(true);
canvas.drawBitmap(bitmap, null, dest, paint);*/
canvas.drawBitmap(bitmap, 0, 0, null);
Path path = new Path();
boolean first = true;
for (int i = 0; i < points.size(); i += 2) {
Point point = points.get(i);
if (first) {
first = false;
path.moveTo(point.x, point.y);
} else if (i < points.size() - 1) {
Point next = points.get(i + 1);
path.quadTo(point.x, point.y, next.x, next.y);
} else {
mlastpoint = points.get(i);
path.lineTo(point.x, point.y);
}
}
canvas.drawPath(path, paint);
}
public boolean onTouch(View view, MotionEvent event) {
// if(event.getAction() != MotionEvent.ACTION_DOWN)
// return super.onTouchEvent(event);
Point point = new Point();
point.x = (int) event.getX();
point.y = (int) event.getY();
if (flgPathDraw) {
if (bfirstpoint) {
if (comparepoint(mfirstpoint, point)) {
// points.add(point);
points.add(mfirstpoint);
flgPathDraw = false;
showcropdialog();
} else {
points.add(point);
}
} else {
points.add(point);
}
if (!(bfirstpoint)) {
mfirstpoint = point;
bfirstpoint = true;
}
}
invalidate();
Log.e("Hi ==>", "Size: " + point.x + " " + point.y);
if (event.getAction() == MotionEvent.ACTION_UP) {
Log.d("Action up*****~~>>>>", "called");
mlastpoint = point;
if (flgPathDraw) {
if (points.size() > 12) {
if (!comparepoint(mfirstpoint, mlastpoint)) {
flgPathDraw = false;
points.add(mfirstpoint);
showcropdialog();
}
}
}
}
return true;
}
private boolean comparepoint(Point first, Point current) {
int left_range_x = (int) (current.x - 3);
int left_range_y = (int) (current.y - 3);
int right_range_x = (int) (current.x + 3);
int right_range_y = (int) (current.y + 3);
if ((left_range_x < first.x && first.x < right_range_x)
&& (left_range_y < first.y && first.y < right_range_y)) {
if (points.size() < 10) {
return false;
} else {
return true;
}
} else {
return false;
}
}
public void fillinPartofPath() {
Point point = new Point();
point.x = points.get(0).x;
point.y = points.get(0).y;
points.add(point);
invalidate();
}
public void resetView() {
points.clear();
paint.setColor(Color.WHITE);
paint.setStyle(Paint.Style.STROKE);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5);
paint.setColor(Color.RED);
points = new ArrayList<Point>();
bfirstpoint = false;
flgPathDraw = true;
invalidate();
}
private void showcropdialog() {
DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Intent intent;
switch (which) {
case DialogInterface.BUTTON_POSITIVE:
cropImage();
break;
case DialogInterface.BUTTON_NEGATIVE:
/*// No button clicked
intent = new Intent(mContext, DisplayCropActivity.class);
intent.putExtra("crop", false);
mContext.startActivity(intent);
bfirstpoint = false;*/
resetView();
break;
}
}
};
AlertDialog.Builder builder = new AlertDialog.Builder(mContext);
builder.setMessage("Do you Want to save Crop or Non-crop image?")
.setPositiveButton("Crop", dialogClickListener)
.setNegativeButton("Non-crop", dialogClickListener).show()
.setCancelable(false);
}
}
Code for cropping bitmap
public void cropImage() {
setContentView(R.layout.activity_picture_preview);
imageView = findViewById(R.id.image);
int widthOfscreen = 0;
int heightOfScreen = 0;
DisplayMetrics dm = new DisplayMetrics();
try {
getWindowManager().getDefaultDisplay().getMetrics(dm);
} catch (Exception ex) {
}
widthOfscreen = dm.widthPixels;
heightOfScreen = dm.heightPixels;
Bitmap bitmap2 = mBitmap;
Bitmap resultingImage = Bitmap.createBitmap(widthOfscreen,
heightOfScreen, bitmap2.getConfig());
Canvas canvas = new Canvas(resultingImage);
Paint paint = new Paint();
Path path = new Path();
for (int i = 0; i < points.size(); i++) {
path.lineTo(points.get(i).x, points.get(i).y);
}
canvas.drawPath(path, paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(bitmap2, 0, 0, paint);
imageView.setImageBitmap(resultingImage);
}
Here what i get result using above code
Cropping image using Finger touch
This image showing result after cropping image
This is my expected output
Please check below screenshot for the same
This Image showing cropping image using Finger touch
This image showing result after cropping image
The Below problems i'am facing in above code
- Unable to set bitmap in full screen using canvas
- If i set bitmap in full screen in canvas than image is stretching
- How to set transparent background to cropped bitmap
- Unable to add border to cropped image
- The result of image Cropping is not as expected
Here are some other post that i have tried so far
none of the above post help to achieve my excepted output
If need more information please do let me know. Thanks in advance. Your efforts will be appreciated.
Cheticamp :
In general, your code looks OK, but I have a few comments:
- Unable to set bitmap in full screen using canvas
If i set bitmap in full screen in canvas than image is stretching
The portion of the image that you are selecting needs to be placed in a smaller bitmap so the layout XML can position it as you like. You are creating a bitmap that is full screen. See the following demo for details.How to set transparent background to cropped bitmap
I am unclear about what the issue is.Unable to add border to cropped image
- The result of image Cropping is not as expected
See below.
Here is a small demo app using your code. You didn't provide an MCVE, so I threw the following together for demonstration purposes. Other than getting the app to function I think that the only change is to draw the border in MainActivity.java. The border width starts at the cut-out path that the user draws and reaches inward to the cut-out. If you want to actually frame the cutout without losing any pixels, then you will need to expand the path to accommodate the frame which I arbitrarily set to 20 pixels.
I also had to create the layouts used, so you may want to look at those. They are posted below.
Here is the demo video with the code to follow:
MainActivity.java
public class MainActivity extends AppCompatActivity {
private Bitmap mBitmap;
private SomeView mSomeView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.dog);
mSomeView = new SomeView(this, mBitmap);
LinearLayout layout = findViewById(R.id.layout);
LinearLayout.LayoutParams lp =
new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT);
layout.addView(mSomeView, lp);
}
public void cropImage() {
setContentView(R.layout.activity_picture_preview);
ImageView imageView = findViewById(R.id.image);
Bitmap fullScreenBitmap =
Bitmap.createBitmap(mSomeView.getWidth(), mSomeView.getHeight(), mBitmap.getConfig());
Canvas canvas = new Canvas(fullScreenBitmap);
Path path = new Path();
List<Point> points = mSomeView.getPoints();
for (int i = 0; i < points.size(); i++) {
path.lineTo(points.get(i).x, points.get(i).y);
}
// Cut out the selected portion of the image...
Paint paint = new Paint();
canvas.drawPath(path, paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(mBitmap, 0, 0, paint);
// Frame the cut out portion...
paint.setColor(Color.WHITE);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(10f);
canvas.drawPath(path, paint);
// Create a bitmap with just the cropped area.
Region region = new Region();
Region clip = new Region(0, 0, fullScreenBitmap.getWidth(), fullScreenBitmap.getHeight());
region.setPath(path, clip);
Rect bounds = region.getBounds();
Bitmap croppedBitmap =
Bitmap.createBitmap(fullScreenBitmap, bounds.left, bounds.top,
bounds.width(), bounds.height());
imageView.setImageBitmap(croppedBitmap);
}
}
SomeView.java
I don't think there were any substantive changes to this class.
public class SomeView extends View implements View.OnTouchListener {
private Paint paint;
private List<Point> points;
int DIST = 2;
boolean flgPathDraw = true;
Point mfirstpoint = null;
boolean bfirstpoint = false;
Point mlastpoint = null;
Bitmap bitmap;
Context mContext;
public SomeView(Context c, Bitmap bitmap) {
super(c);
mContext = c;
this.bitmap = bitmap;
setFocusable(true);
setFocusableInTouchMode(true);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setPathEffect(new DashPathEffect(new float[]{10, 20}, 0));
paint.setStrokeWidth(5);
paint.setColor(Color.RED);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeCap(Paint.Cap.ROUND);
this.setOnTouchListener(this);
points = new ArrayList<Point>();
bfirstpoint = false;
}
public SomeView(Context context, AttributeSet attrs) {
super(context, attrs);
mContext = context;
setFocusable(true);
setFocusableInTouchMode(true);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5);
paint.setColor(Color.RED);
points = new ArrayList<Point>();
bfirstpoint = false;
this.setOnTouchListener(this);
}
public void onDraw(Canvas canvas) {
/*Rect dest = new Rect(0, 0, getWidth(), getHeight());
paint.setFilterBitmap(true); canvas.drawBitmap(bitmap, null, dest, paint);*/
canvas.drawBitmap(bitmap, 0, 0, null);
Path path = new Path();
boolean first = true;
for (int i = 0; i < points.size(); i += 2) {
Point point = points.get(i);
if (first) {
first = false;
path.moveTo(point.x, point.y);
} else if (i < points.size() - 1) {
Point next = points.get(i + 1);
path.quadTo(point.x, point.y, next.x, next.y);
} else {
mlastpoint = points.get(i);
path.lineTo(point.x, point.y);
}
}
canvas.drawPath(path, paint);
}
public boolean onTouch(View view, MotionEvent event) {
// if(event.getAction() != MotionEvent.ACTION_DOWN)
// return super.onTouchEvent(event);
Point point = new Point();
point.x = (int) event.getX();
point.y = (int) event.getY();
if (flgPathDraw) {
if (bfirstpoint) {
if (comparepoint(mfirstpoint, point)) {
// points.add(point);
points.add(mfirstpoint);
flgPathDraw = false;
showcropdialog();
} else {
points.add(point);
}
} else {
points.add(point);
}
if (!(bfirstpoint)) {
mfirstpoint = point;
bfirstpoint = true;
}
}
invalidate();
Log.e("Hi ==>", "Size: " + point.x + " " + point.y);
if (event.getAction() == MotionEvent.ACTION_UP) {
Log.d("Action up*****~~>>>>", "called");
mlastpoint = point;
if (flgPathDraw) {
if (points.size() > 12) {
if (!comparepoint(mfirstpoint, mlastpoint)) {
flgPathDraw = false;
points.add(mfirstpoint);
showcropdialog();
}
}
}
}
return true;
}
private boolean comparepoint(Point first, Point current) {
int left_range_x = (int) (current.x - 3);
int left_range_y = (int) (current.y - 3);
int right_range_x = (int) (current.x + 3);
int right_range_y = (int) (current.y + 3);
if ((left_range_x < first.x && first.x < right_range_x)
&& (left_range_y < first.y && first.y < right_range_y)) {
if (points.size() < 10) {
return false;
} else {
return true;
}
} else {
return false;
}
}
public void fillinPartofPath() {
Point point = new Point();
point.x = points.get(0).x;
point.y = points.get(0).y;
points.add(point);
invalidate();
}
public void resetView() {
points.clear();
paint.setColor(Color.WHITE);
paint.setStyle(Paint.Style.STROKE);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5);
paint.setColor(Color.RED);
points = new ArrayList<Point>();
bfirstpoint = false;
flgPathDraw = true;
invalidate();
}
private void showcropdialog() {
DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Intent intent;
switch (which) {
case DialogInterface.BUTTON_POSITIVE:
((MainActivity) mContext).cropImage();
break;
case DialogInterface.BUTTON_NEGATIVE:
/*// No button clicked
intent = new Intent(mContext, DisplayCropActivity.class); intent.putExtra("crop", false); mContext.startActivity(intent);
bfirstpoint = false;*/ resetView();
break;
}
}
};
AlertDialog.Builder builder = new AlertDialog.Builder(mContext);
builder.setMessage("Do you Want to save Crop or Non-crop image?")
.setPositiveButton("Crop", dialogClickListener)
.setNegativeButton("Non-crop", dialogClickListener).show()
.setCancelable(false);
}
public List<Point> getPoints() {
return points;
}
}
activity_main.xml
<LinearLayout
android:id="@+id/layout"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity"/>
activity_picture_preview.xml
<android.support.constraint.ConstraintLayout x
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/colorPrimary">
<ImageView
android:id="@+id/image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:srcCompat="@drawable/dog" />
</android.support.constraint.ConstraintLayout>
If you want to create a cropped bitmap with a 100px border, use the following code in cropImage():
// Create a bitmap with just the cropped area.
Region region = new Region();
Region clip = new Region(0, 0, fullScreenBitmap.getWidth(), fullScreenBitmap.getHeight());
region.setPath(path, clip);
Rect sourceBounds = region.getBounds();
Rect destBounds =
new Rect(CROPPED_MARGIN, CROPPED_MARGIN, sourceBounds.width() + CROPPED_MARGIN,
sourceBounds.height() + CROPPED_MARGIN);
Bitmap croppedBitmap =
Bitmap.createBitmap(sourceBounds.width() + CROPPED_MARGIN * 2,
sourceBounds.height() + CROPPED_MARGIN * 2, mBitmap.getConfig());
canvas.setBitmap(croppedBitmap);
canvas.drawBitmap(fullScreenBitmap, sourceBounds, destBounds, null);
imageView.setImageBitmap(croppedBitmap);
// Add as member variable.
private static final int CROPPED_MARGIN = 100;