I have a problem I want to convert a Canvas object to Bitmap then perform an operation on a bitmap and then convert this new Bitmap to the Canvas in OnDraw method, this is my code:
protected void onDraw(Canvas canvas)
{
canvas to Bitmap
Bitmap newBitmap = fastblur(bitmap,10);
c = newBitmap to Canvas
m_view.vDraw(c);
}
So you basically want to make a back buffer?
Bitmap backbuffer;
Canvas backbufferCanvas;
protected void onDraw(Canvas canvas){
if(backbuffer != null){
backbuffer = Bitmap.createBitmap(getWidth(), getHeight(), new Bitmap.Config());
backbufferCanvas = new Canvas(backbuffer);
}
//Draw to backbufferCanvas
canvas.draw(backbuffer, 0, 0);
}
Related
I am fetching a Bitmap with Parse on my Android application.
final WeakReference<ImageView> weakImageView = new WeakReference<>(imageViewToMask);
fetchFromParse(getContext(), new Success() {
#Override
public void success(Bitmap image) {
if (weakImageView.get() != null) {
// Here how to make this image a MaskDrawable to mask it?
// MaskedDrawable d = new MaskedDrawable(bitmap, context, [canvas here]?)
// weakImageView.get().setImageDrawable(d);
weakImageView.get().setImageDrawable(image);
}
}
});
Now I want to mask this bitmap with another image, I found this answer in this thread:
public class MaskedDrawable extends Drawable {
public void draw(Bitmap original, Context context, Canvas canvas) {
Bitmap mask = BitmapFactory.decodeResource(context.getResources(), R.drawable.mask_image);
Bitmap result = Bitmap.createBitmap(mask.getWidth(), mask.getHeight(), Config.ARGB_8888);
Canvas tempCanvas = new Canvas(result);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));
tempCanvas.drawBitmap(original, 0, 0, null);
tempCanvas.drawBitmap(mask, 0, 0, paint);
paint.setXfermode(null);
// How do I create this canvas user here?
canvas.drawBitmap(result, 0, 0, new Paint());
}
}
I already have the original bitmap and the context object, but I don't know how to use canvas. What to do?
Thanks for your help!
I want to create the crop bitmap functionality and have referred Android: Free Croping of Image but this sets the bitmap in another imageView.Now I know I can set the cropped bitmap in the canvas but I want to retain the original bitmap and want to do the cropping in onDraw() and not make a different bitmap and then set it in canvas.I have tried to implement the below code in onDraw but there is no cropping and bitmap remains as it is.Pleas help so that I can code this in onDraw() method of the CustomView.
compositeImageView = (ImageView) findViewById(R.id.our_imageview);
Bitmap bitmap2 = BitmapFactory.decodeResource(getResources(),
R.drawable.gallery_12);
Bitmap resultingImage = Bitmap.createBitmap(widthOfscreen,
heightOfScreen, bitmap2.getConfig());
Canvas canvas = new Canvas(resultingImage);
Paint paint = new Paint();
paint.setAntiAlias(true);
Path path = new Path();
for (int i = 0; i < SomeView.points.size(); i++) {
path.lineTo(SomeView.points.get(i).x, SomeView.points.get(i).y);
}
canvas.drawPath(path, paint);
paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
canvas.drawBitmap(bitmap2, 0, 0, paint);
compositeImageView.setImageBitmap(resultingImage);
my onDraw() method
#Override
protected void onDraw(Canvas canvas)
{
Bitmap bitmap1 = bitmap.copy(bitmap.getConfig(), true);
canvas.drawBitmap(bitmap1, 0,0, null);
Paint paint = new Paint();
paint.setAntiAlias(true);
Path path = new Path();
for (int i = 0; i < SomeView.points.size(); i++) {
path.lineTo(SomeView.points.get(i).x, SomeView.points.get(i).y);
}
canvas.drawPath(path, paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(bitmap,0, 0, paint);
}
I need to convert TextView to bitmap. TextView has transparency using the setAlpha() method. I am using following code
Bitmap b = getBitmapFromView(textView , 150);
try {
b.compress(Bitmap.CompressFormat.PNG, 95, new FileOutputStream(watermarkImagePath));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
public Bitmap getBitmapFromView(View view, int alpha) {
view.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
Bitmap bitmap = Bitmap.createBitmap(view.getMeasuredWidth(), view.getMeasuredHeight(),
Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
Paint alphaPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
alphaPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_OUT));
alphaPaint.setColor(Color.TRANSPARENT);
Toast.makeText(VideoCaptureActivity.this, "alpha" + alpha, Toast.LENGTH_LONG).show();
alphaPaint.setAlpha(alpha);
canvas.drawBitmap(bitmap,0,0,alphaPaint);
view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight());
view.draw(canvas);
return bitmap;
}
but the issue is that the result image has no transparency :(
After trying different techniques what worked for me was to make bitmap from view with full opacity and then set tranparency of bitmap. Hope it will help others having same issue
Bitmap b = addTranparencyToBitmap(getBitmapFromView(view), (int)( view.getAlpha() * 255));
try {
b.compress(Bitmap.CompressFormat.PNG, 95, new FileOutputStream(watermarkImagePath));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
public Bitmap getBitmapFromView(View view) {
Bitmap bitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(),
Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
view.draw(canvas);
return bitmap;
}
public Bitmap addTranparencyToBitmap(Bitmap originalBitmap, int alpha) {
Bitmap newBitmap = Bitmap.createBitmap(originalBitmap.getWidth(), originalBitmap.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(newBitmap);
Paint alphaPaint = new Paint();
alphaPaint.setAlpha(alpha);
canvas.drawBitmap(originalBitmap, 0, 0, alphaPaint);
return newBitmap;
}
I'm using the code below to apply a round mask to a bitmap using Square's Picasso library. It works great on devices with android version 3.0 and higher, but it fails to work on gingerbread. There are no errors or exceptions displayed during runtime, instead, the mask simply does not seem to be applied to the original image.
public class CircleTransformation implements Transformation {
#Override
public Bitmap transform(Bitmap source) {
int size = Math.min(source.getWidth(), source.getHeight());
Bitmap finalBitmap = Bitmap.createBitmap(size, size, source.getConfig());
Canvas canvas = new Canvas(finalBitmap);
Paint paint = new Paint();
BitmapShader shader = new BitmapShader(source, BitmapShader.TileMode.CLAMP, BitmapShader.TileMode.CLAMP);
paint.setShader(shader);
paint.setAntiAlias(true);
float radius = size / 2f;
canvas.drawCircle(radius, radius, radius, paint);
source.recycle();
return finalBitmap;
}
#Override
public String key() {
return "circle";
}
}
All of the methods I'm using seem to be available since API level 1 so I'm kinda stuck. Any idea what could be the issue?
pd. this code was based on: https://gist.github.com/julianshen/5829333
I still don't know why this code doesn't work in gingerbread, but I was able to get it to work by using a round mask image:
public class PreHoneycombCircleTransformation implements Transformation {
#Override
public Bitmap transform(Bitmap source) {
int dim = Constants.BUBBLE_WIDTH;
Canvas canvas = new Canvas();
// placeholder for final image
Bitmap result = Bitmap.createBitmap(dim, dim, Bitmap.Config.ARGB_8888);
canvas.setBitmap(result);
Paint paint = new Paint();
paint.setFilterBitmap(false);
// resize image fills the whole canvas
canvas.drawBitmap(source, null, new Rect(0, 0, dim, dim), paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
canvas.drawBitmap(Util.getMaskImage(), 0, 0, paint);
paint.setXfermode(null);
if(result != source) {
source.recycle();
}
return result;
}
#Override
public String key() {
return "pre_circle";
}
}
The class below is another alternative, works both in Gingerbread and ICS. The code in the CircleTransformation doesn't work in ICS for me.
public class CircleTransform implements Transformation {
#Override
public Bitmap transform(Bitmap source) {
int size = Math.min(source.getWidth(), source.getHeight());
float radius = size / 2f;
final Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(new BitmapShader(source, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));
Bitmap output = Bitmap.createBitmap(source.getWidth(), source.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(output);
canvas.drawCircle(radius, radius, radius, paint);
if (source != output) {
source.recycle();
}
return output;
}
#Override
public String key() {
return "circle";
}
}
I'm trying to save as an image the contents of a WebView with a canvas drawing on top of it. I've tried two methods:
Picture picture = drawView.capturePicture();
Bitmap bmp = pictureDrawable2Bitmap(new PictureDrawable(picture));
MediaStore.Images.Media.insertImage(
getContentResolver(), bitmap,
"image" + ".png", "drawing");
private static Bitmap pictureDrawable2Bitmap(PictureDrawable pictureDrawable){
Bitmap bitmap = Bitmap.createBitmap(
pictureDrawable.getIntrinsicWidth() ,pictureDrawable.getIntrinsicHeight(),Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
canvas.drawPicture(pictureDrawable.getPicture());
return bitmap;
}
This gets me the entire WebView page but without the Canvas drawing.
Method 2:
Bitmap bitmap = Bitmap.createBitmap(drawView.getWidth(), drawView.getHeight(),
Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
drawView.draw(canvas);
MediaStore.Images.Media.insertImage(
getContentResolver(), bitmap,
"image" + ".png", "drawing");
drawView.destroyDrawingCache();
This way I get both the canvas and WebView but it only captures it at the current zoom level. Which means if I save it while zoomed in it will only save the current view state, not the entire image. It's also lower quality.
Any suggestion on how to get them together?
Some of the code:
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
canvasBitmap = Bitmap.createBitmap(w + 1500, h + 1500, Bitmap.Config.ARGB_8888);
drawCanvas = new Canvas(canvasBitmap);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
clipBounds = canvas.getClipBounds();
canvas.save();
//canvas.translate(clipBounds.left, clipBounds.top);
drawPaint.setStrokeWidth(8/mScaleFactor);
canvas.scale(mScaleFactor, mScaleFactor, 0, 0);
if(!pathsDrawn) {
canvas.drawPath(drawPath, drawPaint);
pathsDrawn = true;
}
canvas.drawBitmap(canvasBitmap, 0, 0, canvasPaint);
canvas.restore();
}
WebView settings:
final DrawingView drawView;
drawView = (DrawingView) findViewById(R.id.pdf);
drawView.setDrawingCacheEnabled(true);
WebSettings webSettings = drawView.getSettings();
webSettings.setLoadWithOverviewMode(true);
webSettings.setUseWideViewPort(true);
webSettings.setBuiltInZoomControls(true);
webSettings.setDefaultZoom(ZoomDensity.FAR);
webSettings.setSupportZoom(true);
webSettings.setDisplayZoomControls(false);
String data = "someurl.jpg"
drawView.loadUrl(data);
drawView.setDrawingCacheEnabled(true);
Picture picture = drawView.capturePicture();
Bitmap bmp = pictureDrawable2Bitmap(new PictureDrawable(picture));
MediaStore.Images.Media.insertImage(getContentResolver(), overlayMark(bmp, DrawingView.canvasBitmap),
"dfdsf" + ".png", "drawing");
EDIT*
Got it working for the most part. I basically drew two bitmaps with canvas. However, the web image bitmap and the drawing bitmap do not scale correctly. I had to offset this by scaling the drawing using a Matrix and redrawing the bitmap before overlaying it on the web bitmap. For some reason, scale it to 1.5f makes it line up perfectly, at least on the 10in tablet I'm testing it on. If anyone has any more insight on this or how to make it better let me know.
Matrix matrix = new Matrix();
matrix.postScale(1.5f, 1.5f);
Picture picture = drawView.capturePicture();
Bitmap bmp = pictureDrawable2Bitmap(new PictureDrawable(picture));
Bitmap resizedBitmap = Bitmap.createBitmap(DrawingView.canvasBitmap, 0, 0, DrawingView.canvasBitmap.getWidth(), DrawingView.canvasBitmap.getHeight(), matrix, false);
MediaStore.Images.Media.insertImage(getContentResolver(), overlayMark(bmp, resizedBitmap),
"dfdsf" + ".png", "drawing");
private static Bitmap pictureDrawable2Bitmap(PictureDrawable pictureDrawable){
Bitmap bitmap = Bitmap.createBitmap(
pictureDrawable.getIntrinsicWidth() ,pictureDrawable.getIntrinsicHeight(),Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
canvas.drawPicture(pictureDrawable.getPicture());
return bitmap;
}
private Bitmap overlayMark(Bitmap bmp1, Bitmap bmp2) {
int bh = bmp1.getHeight();
int bw = bmp1.getWidth();
Bitmap bmOverlay = Bitmap.createBitmap(bw,bh,Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bmOverlay);
canvas.drawBitmap(bmp1, 0, 0, null);
canvas.drawBitmap(bmp2, 0, 0, null);
return bmOverlay;
}