Develop Reference

Fit image inside png Image (Frame)

I have a png image which I want to use as a frame for images in ImageView.
Sorry, it's white that's why invisible
Like this but with sides curved
What is the solution?
I've tried by converting png to patch 9, setting background of parent and source of image view, but none worked. Image doesn't fit inside.

I've done it using PorterDuff. Designed an extra image just with curved border and applied PorterDuff.Mode.SRC_OVER inside setImageResource of Custom Image View.
Here is the overriden function
#Override
public void setImageResource(int resId) {
Bitmap rawBmp = BitmapFactory.decodeResource(getContext().getResources(), resId);
Bitmap rawMask = BitmapFactory.decodeResource(getContext().getResources(), R.drawable.image_frame_arc_filled);
Bitmap rawBorderMask = BitmapFactory.decodeResource(getContext().getResources(), R.drawable.image_frame_arc);
Bitmap bmp = Bitmap.createScaledBitmap(rawBmp, rawBmp.getWidth(), rawBmp.getHeight(), true);
Bitmap mask = Bitmap.createScaledBitmap(rawMask, bmp.getWidth(), bmp.getHeight(), true);
Bitmap borderMask = Bitmap.createScaledBitmap(rawBorderMask, mask.getWidth(), mask.getHeight(), true);
Bitmap bitmap = Bitmap.createBitmap(mask.getWidth(), mask.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
canvas.drawBitmap(bmp, 0, 0, null);
Paint maskPaint = new Paint();
maskPaint.setXfermode(
new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
canvas.drawBitmap(mask, 0, 0, maskPaint);
maskPaint = new Paint();
maskPaint.setXfermode(
new PorterDuffXfermode(PorterDuff.Mode.SRC_OVER));
canvas.drawBitmap(borderMask, 0, 0, maskPaint);
this.setImageBitmap(bitmap);
}

How to set width and height of Android canvas in pixels?

I need to create a canvas element with exact pixel size (500x500). How do I set width/height in px?

Might not be applicable in your case, but this works for me
Bitmap animation = BitmapFactory.decodeResource(mContext.getResources(), resourceId, mBitmapOptions); //Get a bitmap from a image file
// Create a bitmap for the part of the screen that needs updating.
Bitmap bitmap = Bitmap.createBitmap(animation.getWidth(), animation.getHeight(), BITMAP_CONFIG);
bitmap.setDensity(DisplayMetrics.DENSITY_DEFAULT);
Canvas canvas = new Canvas(bitmap);
You have create bitmap of the size which you want. and then Canvas canvas = new Canvas(bitmap);
This sets the canvas to the size of the bitmap

just like view.height = 100, so this view's height is 100 in px unit

Android Image Masking with Rotate & Scale

How to mask image such as we can scale/zoom/rotate the background image but not the mask?
I should be able to zoom the image in this mask but it is scaling whole image.
Suggest me a way to achieve this, I'm creating a photo collage app.
Blue color is background of Layout.
The white color is for mask
I'm able to achieve this type of layout with masking, but when I apply MultiTouchListener to scale and zoom, it will scale the whole image with mask and not the image inside it.
private void getMaskedBitmap() {
Bitmap bgBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.background_drawable);
ImageView bg = (ImageView) findViewById(R.id.bg);
bg.setImageBitmap(bgBitmap);
Bitmap.Config conf = Bitmap.Config.ARGB_8888;
Bitmap emptyBitmap = Bitmap.createBitmap(bgBitmap.getWidth(), bgBitmap.getHeight(), conf);
Canvas canvasBmp = new Canvas(bgBitmap);
ImageView mImageView = (ImageView) findViewById(R.id.troll_face);
Bitmap original = BitmapFactory.decodeResource(getResources(), R.drawable.random_drawable);
Bitmap mask = BitmapFactory.decodeResource(getResources(), R.drawable.mask_drawable);
original = Bitmap.createScaledBitmap(original, mask.getWidth(), mask.getHeight(), true);
Bitmap result = Bitmap.createBitmap(mask.getWidth(), mask.getHeight(), Config.ARGB_8888);
Canvas mCanvas = new Canvas(result);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
mCanvas.drawBitmap(original, 0, 0, null);
mCanvas.drawBitmap(mask, 0, 0, paint);
paint.setXfermode(null);
mImageView.setImageBitmap(result);
//mImageView.setScaleType(ScaleType.FIT_XY);
mImageView.setBackgroundResource(R.drawable.background_drawable);
bg.setOnTouchListener(new MultiTouchListener());
mImageView.invalidate();
}
Exception on line
Canvas canvasBmp = new Canvas(bgBitmap);
java.lang.IllegalStateException: Immutable bitmap passed to Canvas constructor

I cannot provide you code but here is what you should do:
Get background image as bitmap and draw it on view's canvas.
Create an new (empty) bitmap of same size (use Bitmap.Config.ARGB_8888) and get its canvas, here you will draw mask.
Canvas canvasBmp = new Canvas(bmp);
Now draw bmp on view's canvas. So, that you can get mask effect on image.
Zoom (re-size etc whatever you want) background bitmap image.
Invalidate your view, and follow all steps again

Create bitmap overlay with some information

I've created a Bitmap [Thumbnail] which is fetched after picking a video from gallery.
Snippet:-
bm= ThumbnailUtils.createVideoThumbnail(currentFileUri.getPath(), MediaStore.Video.Thumbnails.MICRO_KIND);
I'm putting these bitmap in Gallery adapter which is meant from images only, tht's y i'm creating thumbnail of Video and putting there. But
I want to show some difference between image and video in Gallery Strip which can be done by overlaying VideoThumbnail with something like Play Option.
Tried to OverLay my Bitmap with Small Play Icon but it throws NullPointerException on Bitmap.CreateScaledBitmap(..)
Snippet:-
bm= ThumbnailUtils.createVideoThumbnail(currentFileUri.getPath(), MediaStore.Video.Thumbnails.MICRO_KIND);
Bitmap change = null;
Bitmap border = BitmapFactory.decodeResource(getResources(), android.R.drawable.ic_media_play);
int width = bm.getWidth();
int height = bm.getHeight();
change = Bitmap.createScaledBitmap(change, width, height, false);
Canvas canvas = new Canvas(change);
Bitmap scaledBorder = Bitmap.createScaledBitmap(border,width/2,height/2, false);
canvas.drawBitmap(scaledBorder, 0, 0,null);
Adding that newly Overlay Created bitmap on my adapter.
AddIPDActivity.this.data.add(bm);

Created Overlay BitMap with LayerDrawable
Bitmap on which overlay need to be done.
bm = ThumbnailUtils.createVideoThumbnail(currentFileUri.getPath(),MediaStore.Video.Thumbnails.MICRO_KIND);
LayerDrawable applied on Bitmap with custom image on it.
Resources r = getResources();
Drawable[] layers = new Drawable[2];
layers[0] = new BitmapDrawable(bm);
layers[1] = r.getDrawable(android.R.drawable.ic_media_play);
LayerDrawable layerDrawable = new LayerDrawable(layers);
Added Bitmap on Gallery - Adapter.
this.data.add(drawableToBitmap(geSingleDrawable(layerDrawable))); //data is adapter for Gallery.
Converting LayerDrawable into BitMap:-
LayerDrawable -> Drawable -> BitMap
public static Drawable geSingleDrawable(LayerDrawable layerDrawable){
int resourceBitmapHeight = 136, resourceBitmapWidth = 153;
float widthInInches = 0.9f;
int widthInPixels = (int)(widthInInches * SmartConsultant.getApplication().getResources().getDisplayMetrics().densityDpi);
int heightInPixels = widthInPixels * resourceBitmapHeight / resourceBitmapWidth;
int insetLeft = 10, insetTop = 10, insetRight = 10, insetBottom = 10;
layerDrawable.setLayerInset(1, insetLeft, insetTop, insetRight, insetBottom);
Bitmap bitmap = Bitmap.createBitmap(widthInPixels, heightInPixels, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
layerDrawable.setBounds(0, 0, widthInPixels, heightInPixels);
layerDrawable.draw(canvas);
BitmapDrawable bitmapDrawable = new BitmapDrawable(SmartConsultant.getApplication().getResources(), bitmap);
bitmapDrawable.setBounds(0, 0, widthInPixels, heightInPixels);
return bitmapDrawable;
}
public static Bitmap drawableToBitmap (Drawable drawable) {
if (drawable instanceof BitmapDrawable) {
return ((BitmapDrawable)drawable).getBitmap();
}
Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);
return bitmap;
}

u r getting NPE because
Bitmap change = null;
change = Bitmap.createScaledBitmap(change, width, height, false);
change is always null. U r passing a null value.So, before passing change as a parameter of createScaledBitmap(parameters) assign a bitmap to change after that call this
change = Bitmap.createScaledBitmap(change, width, height, false);

How to clip and fill a canvas using an alpha mask

I have some .png icons that are alpha masks. I need to render them as an drawable image using the Android SDK.
On the iPhone, I use the following to get this result, converting the "image" alpha mask to the 'imageMasked' image using black as a fill:
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(NULL, thumbWidth,
thumbHeight, 8, 4*thumbWidth, colorSpace, kCGImageAlphaPremultipliedFirst);
CGRect frame = CGRectMake(0,0,thumbWidth,thumbHeight);
CGContextClipToMask(context, frame, [image CGImage]);
CGContextFillRect(context, frame);
CGImageRef imageMasked = CGBitmapContextCreateImage(context);
CGContextRelease(context);
How do I accomplish the above in Android SDK?
I've started to write the following:
Drawable image = myPngImage;
final int width = image.getMinimumWidth();
final int height = image.getMinimumHeight();
Bitmap imageMasked = Bitmap.createBitmap(width,
height, Config.ARGB_8888);
Canvas canvas = new Canvas(iconMasked);
image.draw(canvas); ???
I'm not finding how to do the clipping on imageMasked using image.

Solved:
Drawable icon = An_Icon_That_Is_An_Alpha_Mask;
int width = icon.getIntrinsicWidth();
int height = icon.getIntrinsicHeight();
Bitmap bm = Bitmap.createBitmap(width, height, Bitmap.Config.ALPHA_8);
Canvas canvas = new Canvas(bm);
icon.setBounds(new Rect(0,0,width,height));
icon.draw(canvas);