I have this image that comes back from an API, which represents the users avatar:
However, my graphics department has designed the app to mask the image to make it look like this at runtime (to match our existing design of sharp edges, etc):
Notice the small edge cutout on the bottom left?
I'd love to be able to create a custom ImageView that handled this for me. Unfortunately I'm not sure how to go about doing that. How can I create the bottom image in a custom ImageView. Is this possible? Do I mask it? If so, how?
Thanks!
Using Path and xfer modes to draw on canvas can do the trick. Check this answer how to draw pic to Closed curve area
I think the easiest way to do is to use 2 ImageViews, one with the photo and other above it with a mask for the photo, in your case it would be all transparent except the bottom left to create the cutout with the background color.
You may be able to use android.graphics.Path to draw the complex shape you want. I found this very helpful for a simple custom View, but it seems like you can do a lot with it:
http://developer.android.com/reference/android/graphics/Path.html
Simple code sample for a shaded rectangle:
private Path mRectanglePath;
...
// draw the path
mRectanglePath = new Path();
mRectanglePath.addRect(mLeft, mTop, mRight, mBottom, Path.Direction.CW);
// draw the fill
Paint paint = new Paint();
paint.setColor(Color.RED);
paint.setAlpha(64);
canvas.drawPath(mRectanglePath, paint);
Related
I have a custom view wich contain some bitmaps and I want to set shadows for them, for that, I use this code:
shadowPaints=new Paint(Paint.ANTI_ALIAS_FLAG);
shadowPaints.setShadowLayer(10.0f, 3.0f, 2.0f, Color.BLACK);
canvas.drawBitmap(bmp, matrix, shadowPaints);
setLayerType(LAYER_TYPE_SOFTWARE, shadowPaints);
and my result is
as you can see my shadow actually is another bitmap with different x and y position but what I want is my shadow be a solid color
bitmap.
can anyone help me about this?
setShadowLayer is actually meant for putting shadows on text.
If you already know the bitmap you want to draw, you can just add a shadow in PhotoShop and draw the bitmap and shadow all at once.
If you don't want to do that, you could make a shadow by making a copy of the image, using a PorterDuff filter to make it all grey, use Renderscript to blur the image, and draw it on the canvas at an x,y offset before drawing the actual image on top of it.
Personally, I think PhotoShop is a lot easier.
My app teaches how to write letters and I want to draw for example letter "A" programmatically.
I do not want to draw it pixel by pixel(it is so hard!)
What other ways to do that?
UPDATE:
I want to show how to write "A" not just showing A in the screen
Romain Guy recently wrote a blog post on how to do path tracing using paths. If you can construct paths yourself (or finding a method for creating correct paths for letters) you could use the information from his blog to do something.
http://www.curious-creature.org/2013/12/21/android-recipe-4-path-tracing/#more-1904
Good luck
if you are using Canvas, you can draw text on canvas using this:
canvas.drawText("A",marginFromLeft,MarginFromRight, paint);
also you can draw bitmap of A on canvas using this:
canvas.drawBitmap(bmp,marginLeft,marginTop, paint);
after drawing this,you can animate an other image like circle using animationSet:
anim One: animate circle moving from bottom left to top center of A
anim Two: animate circle moving from top center of A to bottom left Right
anim Three: animate circle moving from left-verticaly-center to right-verticaly-center.
Imagine that I have a rectangle image. How could I create a style like the next one?
I mean, cropping the image into a circle, add the border, the shadow and the gross /shine effect. Until now, I only have tried this snippet code to crop the image: Cropping circular area from bitmap in Android but just that. I have no idea how to do the remaining components in Android.
An easy way to achieve this effect is to use Canvas.drawCircle() and a BitmapShader:
BitmapShader s = new BitmapShader(myPhoto, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
Paint p = new Paint();
p.setShader(s);
myCanvas.drawCircle(centerX, centerY, radius, p);
To do the shadow, simply call Paint.setShadowLayer() on the paint (this will only work if you draw the effect into an offscreen Bitmap or if your View uses a software layer – set by calling View.setLayerType() –).
The border can be drawn by drawing another circle on top, using the Paint.Style.STROKE style (that you can set by calling Paint.setStyle()).
Finally you can draw the gloss by drawing a circle, oval or Path on top of your very first circle. You'll need to use a LinearGradient shader on your paint and you'll also need to clip the gloss. You can do this in two ways:
If you are drawing the entire effect into a Bitmap, which is what I would recommend, simply set the paint's Xfermode to a new PorterDuffXfermode(PorterDuff.Mode.SRC_IN).
If you are drawing the effect directly on screen you can simply use Canvas.clipPath() to set a circular clip. Note that this will work with hardware acceleration only as of Android 4.3.
I want to make in my app possibilty to draw circles by user. The drawing is quite simple - user just press on canvas somewhere and then predefined circle
The difficult part here is to draw it with some drawable (picture) as a fill. It is quite simple when it is about rectangle. Then you just need to write:
Drawable drawable = getResources().getDrawable(R.drawable.my_background_picture);
drawable.setBounds(myRectangle);
drawable.draw(myCanvas);
Everything is done on onDraw() method of my custom view.
Unfortunatelly there isn't such simple method to make it with circle. The one that I've found is slight modification from Vogella's tutorial:
InputStream resource = getResources().openRawResource(R.drawable.sand);
Bitmap bitmap = BitmapFactory.decodeStream(resource);
BitmapShader shader;
shader = new BitmapShader(bitmap, Shader.TileMode.CLAMP,Shader.TileMode.CLAMP);
paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(shader);
myCanvas.drawRoundRect(myRectangle, 120, 120, paint);
At first sight it looks ok, but it's not. This commands make just something like frame on a picture below, so you move hollow circle on a picture and that's all. Not as with rectangle where you actually move rectangular bitmap.
So, my question is - Is there a way to make circle drawable that can be also moved/resized?
Why make a drawable? You can easily draw a circle via the canvas.drawCircle command. You can also easily make one via a Path object.
Edit:
If you need a drawable, try making a ShapeDrawable based off an OvalShape.
I have a question about drawBitmap.
android.graphics.Canvas.drawBitmap(Bitmap bitmap, float left, float top, Paint paint)
What does that Paint paint? For example I have a picture.jpg and I make
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.picture);
paint = new Paint();
paint.setColor(Color.BLUE);
canvas.drawBitmap(bitmap, 0, 0, paint);
What can I do with that "paint" when I have a real picture not some canvas.drawCircle. Is there any way I can change pictures color or something like that?
Yes and another question. For example I draw circle in mspaint in 80x80 size and my background stays plain white. When I use that drawing in my program it shows circle + that white background. Is there any way that there will be displayed only circle without background. Maybe somebody can suggest some program in which I can make that happen or which code should I use in my program? (circle is just example, there can be anything)
Yes and excuse to use circle's background same as program's background is not appropriate, because my program's background isn't white or black or any other color, it is picture.
Paint objects can affect the rendering of the Bitmap. For example, they be used to mask the drawing of the Bitmap.
Save your circle as a PNG or GIF, and set the background as transparent (I do not know if MS Paint can do this).
i suggest gimp for image editing with transparency.
start a new image, delete the default layer, add a transparent layer, then paste your image over that. you can use the fuzzy select tool to trim any white space, then save as .png and you have a transparent image!