protected override void OnDraw (Canvas canvas)
{
canvas.DrawColor (Color.White);
canvas.Translate (10, 10);
canvas.SaveLayerAlpha (0, 0, 200, 200, 0x88, SaveFlags.All);
mPaint.Color = Color.Red;
canvas.DrawCircle (75, 75, 75, mPaint);
mPaint.Color = Color.Blue;
canvas.DrawCircle (125, 125, 75, mPaint);
canvas.Restore ();
}
public void draw(Canvas canvas) {
int width = mBounds.Width ();
int height = mBounds.Height();
int cx = width / 2;
int cy = height / 2;
Boolean drawTriggerWhileFinishing = false;
int restoreCount = canvas.Save();
canvas.ClipRect(mBounds);
if (mRunning || (mFinishTime > 0)) {
long now = AnimationUtils.CurrentAnimationTimeMillis();
long elapsed = (now - mStartTime) % ANIMATION_DURATION_MS;
long iterations = (now - mStartTime) / ANIMATION_DURATION_MS;
float rawProgress = (elapsed / (ANIMATION_DURATION_MS / 100f));
// If we're not running anymore, that means we're running through
// the finish animation.
if (!mRunning) {
// If the finish animation is done, don't draw anything, and
// don't repost.
if ((now - mFinishTime) >= FINISH_ANIMATION_DURATION_MS) {
mFinishTime = 0;
return;
}
// Otherwise, use a 0 opacity alpha layer to clear the animation
// from the inside out. This layer will prevent the circles from
// drawing within its bounds.
long finishElapsed = (now - mFinishTime) % FINISH_ANIMATION_DURATION_MS;
float finishProgress = (finishElapsed / (FINISH_ANIMATION_DURATION_MS / 100f));
float pct = (finishProgress / 100f);
// Radius of the circle is half of the screen.
float clearRadius = width / 2;//* INTERPOLATOR.getInterpolation(pct);
mClipRect.Set(cx - clearRadius, 0, cx + clearRadius, height);
canvas.SaveLayerAlpha(mClipRect, 0, 0);
// Only draw the trigger if there is a space in the center of
// this refreshing view that needs to be filled in by the
// trigger. If the progress view is just still animating, let it
// continue animating.
drawTriggerWhileFinishing = true;
}
// First fill in with the last color that would have finished drawing.
if (iterations == 0) {
canvas.DrawColor (Android.Graphics.Color.Blue);
} else {
if (rawProgress >= 0 && rawProgress < 25) {
canvas.DrawColor(Android.Graphics.Color.AliceBlue);
} else if (rawProgress >= 25 && rawProgress < 50) {
canvas.DrawColor (Android.Graphics.Color.Blue);
} else if (rawProgress >= 50 && rawProgress < 75) {
canvas.DrawColor (Android.Graphics.Color.BlueViolet);
} else {
canvas.DrawColor (Android.Graphics.Color.CadetBlue);
}
}
// Then draw up to 4 overlapping concentric circles of varying radii, based on how far
// along we are in the cycle.
// progress 0-50 draw mColor2
// progress 25-75 draw mColor3
// progress 50-100 draw mColor4
// progress 75 (wrap to 25) draw mColor1
if ((rawProgress >= 0 && rawProgress <= 25)) {
float pct = (((rawProgress + 25) * 2) / 100f);
drawCircle(canvas, cx, cy, mColor1, pct);
}
if (rawProgress >= 0 && rawProgress <= 50) {
float pct = ((rawProgress * 2) / 100f);
drawCircle(canvas, cx, cy, mColor2, pct);
}
if (rawProgress >= 25 && rawProgress <= 75) {
float pct = (((rawProgress - 25) * 2) / 100f);
drawCircle(canvas, cx, cy, mColor3, pct);
}
if (rawProgress >= 50 && rawProgress <= 100) {
float pct = (((rawProgress - 50) * 2) / 100f);
drawCircle(canvas, cx, cy, mColor4, pct);
}
if ((rawProgress >= 75 && rawProgress <= 100)) {
float pct = (((rawProgress - 75) * 2) / 100f);
drawCircle(canvas, cx, cy, mColor1, pct);
}
if (mTriggerPercentage > 0 && drawTriggerWhileFinishing) {
// There is some portion of trigger to draw. Restore the canvas,
// then draw the trigger. Otherwise, the trigger does not appear
// until after the bar has finished animating and appears to
// just jump in at a larger width than expected.
canvas.RestoreToCount(restoreCount);
restoreCount = canvas.Save();
canvas.ClipRect(mBounds);
drawTrigger(canvas, cx, cy);
}
// Keep running until we finish out the last cycle.
ViewCompat.PostInvalidateOnAnimation(mParent);
} else {
// Otherwise if we're in the middle of a trigger, draw that.
if (mTriggerPercentage > 0 && mTriggerPercentage <= 1.0) {
drawTrigger(canvas, cx, cy);
}
}
canvas.RestoreToCount(restoreCount);
}