private void drawTriangle(Canvas c, float startAngle, float sweepAngle, Rect bounds) {
if (mShowArrow) {
if (mArrow == null) {
mArrow = new Path();
mArrow.setFillType(Path.FillType.EVEN_ODD);
} else {
mArrow.reset();
}
// Adjust the position of the triangle so that it is inset as
// much as the arc, but also centered on the arc.
float inset = (int) mStrokeInset / 2 * mArrowScale;
float x = (float) (mRingCenterRadius * Math.cos(0) + bounds.exactCenterX());
float y = (float) (mRingCenterRadius * Math.sin(0) + bounds.exactCenterY());
// Update the path each time. This works around an issue in SKIA
// where concatenating a rotation matrix to a scale matrix
// ignored a starting negative rotation. This appears to have
// been fixed as of API 21.
mArrow.moveTo(0, 0);
mArrow.lineTo(mArrowWidth * mArrowScale, 0);
mArrow.lineTo((mArrowWidth * mArrowScale / 2), (mArrowHeight * mArrowScale));
mArrow.offset(x - inset, y);
mArrow.close();
// draw a triangle
mArrowPaint.setColor(mColors[mColorIndex]);
c.rotate(
startAngle + sweepAngle - ARROW_OFFSET_ANGLE,
bounds.exactCenterX(),
bounds.exactCenterY());
c.drawPath(mArrow, mArrowPaint);
}
}
private void computeGlyphPath() {
drawableArea.set(getBounds());
drawableArea.inset(padding, padding);
glyphPaint.getTextPath(glyph, 0, 1, 0, 0, glyphPath);
// Add an extra path point to fix the icon remaining blank on a Galaxy Note 2 running 4.1.2.
glyphPath.computeBounds(glyphPathBounds, false);
final float centerX = glyphPathBounds.centerX();
final float centerY = glyphPathBounds.centerY();
glyphPath.moveTo(centerX, centerY);
glyphPath.lineTo(centerX + 0.001f, centerY + 0.001f);
final float areaWidthF = (float) drawableArea.width();
final float areaHeightF = (float) drawableArea.height();
final float scaleX = areaWidthF / glyphPathBounds.width();
final float scaleY = areaHeightF / glyphPathBounds.height();
final float scaleFactor = Math.min(scaleX, scaleY);
glyphPathTransform.setScale(scaleFactor, scaleFactor);
glyphPath.transform(glyphPathTransform);
// TODO this two pass calculation irks me.
// It has to be possible to push this into a single Matrix transform; what makes it hard is
// that the origin of Text is not top-left, but baseline-left so need to account for that.
glyphPath.computeBounds(glyphPathBounds, false);
final float areaLeftF = (float) drawableArea.left;
final float areaTopF = (float) drawableArea.top;
float transX = areaLeftF - glyphPathBounds.left;
transX += 0.5f * Math.abs(areaWidthF - glyphPathBounds.width());
float transY = areaTopF - glyphPathBounds.top;
transY += 0.5f * Math.abs(areaHeightF - glyphPathBounds.height());
glyphPath.offset(transX, transY);
invalidateSelf();
}
@Override
protected void onDraw(Canvas canvas) {
Bitmap sweet = BitmapFactory.decodeResource(getResources(), R.drawable.sq);
canvas.drawColor(color.black);
canvas.drawBitmap(sweet, 0, 0, null);
Paint paint = new Paint();
// draw a red circle
paint.setColor(Color.RED);
canvas.drawCircle(20, 50, 25, paint);
// a blue circle with antialiasing turned on
paint.setAntiAlias(true);
paint.setColor(Color.BLUE);
canvas.drawCircle(60, 50, 25, paint);
// Now we wiil create some triangles.Create a Path object to store
// out triangle's segments. Use.offset to draw in many locations.
paint.setStyle(Paint.Style.FILL_AND_STROKE);
paint.setStrokeWidth(2);
paint.setColor(Color.GREEN);
Path path = new Path();
path.moveTo(4, -10);
path.lineTo(20, 0);
path.lineTo(-9, 0);
path.close();
path.offset(60, 40);
canvas.drawPath(path, paint);
path.offset(90, 100);
canvas.drawPath(path, paint);
path.offset(80, 150);
canvas.drawPath(path, paint);
// Now draw a text using FILL style:
paint.setStyle(Paint.Style.FILL);
paint.setAntiAlias(true);
paint.setTextSize(20);
canvas.drawText("Hello Android! Fill...", 50, 230, paint);
// rotate the text, and you can draw it where you want:
int x = 75;
int y = 185;
paint.setColor(Color.GRAY);
paint.setTextSize(25);
String rotatedtext = "Rotated hellowandroid:)";
// draw bounding rect befor rotating text:
Rect rect = new Rect();
paint.getTextBounds(rotatedtext, 0, rotatedtext.length(), rect);
canvas.translate(x, y);
paint.setStyle(Paint.Style.FILL);
canvas.drawText("Rotated helloandroid :)", 0, 0, paint);
paint.setStyle(Paint.Style.STROKE);
canvas.drawRect(rect, paint);
canvas.translate(-x, -y);
paint.setColor(Color.RED);
canvas.rotate(-45, x + rect.exactCenterX(), y + rect.exactCenterY());
paint.setStyle(Paint.Style.FILL);
canvas.drawText(rotatedtext, x, y, paint);
// draw a draw a thick dashed line in angle
DashPathEffect dashPath = new DashPathEffect(new float[] {10, 40}, 1);
paint.setPathEffect(dashPath);
paint.setStrokeWidth(8);
canvas.drawLine(0, 60, 320, 300, paint);
}
