how to drawText transparent with background Path in Canvas Drawable?
https://i.stack.imgur.com/RkS41.jpg
Do you want a transparent background with text on it like the first battery indicator?
If so create two Paint objects: one with alpha value (from 0 to 255) to draw the transparent background, the other one to draw your text.
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How would you draw something like this programmatically in a ondraw method? I know how to draw lines or squares, but to have an image inside a squarebox that has an arrow, is kind of confusing for me
Thank you
Just break the drawing up in different elements:
a gray box
a white rounded rectangle
a white rectangle
a blue rectangle
a blue rounded rectangle
a blue triangle
a red heart (I would just try to find a font with a nice heart)
the text in white.
Draw it all to the canvas in this order and you are fine.
Is that possible to draw text on Canvas with gradient color in Andorid?
For example, draw letter A with top part is red while bottom part is blue?
Thanks
I want to create a little scratch game. The problem is, that I can't figure out how to erase pixels from an image in android (like the eraser in gimp / photoshop).
The image is an .png with alpha channel.
AIUI, drawing operations on a canvas blend a transparent pixel with the prior value of the pixel. This is by default, and you can see it by setting a canvas to black and drawing a fully transparent shape onto it, and then drawing the underlying bitmap over an image of another canvas (result: a fully black canvas), or by setting a canvas to a partially transparent color and, drawing a shape of another partially transparent color, and then drawing this over an image (result: the original image is tinted by the first color, outside the shape; within the shape, it's tinted by both transparent colors). I don't know the blending method used by default, and looking through the docs just makes me wish I knew what book to buy so I can understand how to use what's available.
So I would set pixels to transparent by setting them 'directly', with Bitmap methods, rather than with canvas operations. Although if you need to punch a transparent shape into an overlay, you can draw the shape with a solid non-transparent color, and then manipulate the bitmap directly, mapping this color to the transparent color.
Bitmap docs. Prefer getPixels() and setPixels() to a method-call per pixel.
EDIT: ...er, did I misunderstand? You want to 'erase' pixels as in a paint program? Then just draw whatever the background color is. There's no erasure involved.
How can i draw path with translucent (semi-transparent) band on canvas (method onDraw in my custom View)? I draw path line by bezier curve (method path.quadTo), but i want to around the line was illuminated translucent band?
I tried several approaches:
Try draw path by paint with semi-transparent color 0x8800ff00.
Try use paint.setShader(new BitmapShader(semi-transparent background image)) and draw path by this paint;
But they did not help. There was no effect of translucency.
Does it work if you first draw the curve using a Paint with a much bigger StrokeWidth and a transparent color (this being the glow), then draw your first curve on top of it?
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!