diff options
Diffstat (limited to 'src/android/support/wearable/view/ProgressDrawable.java')
| -rw-r--r-- | src/android/support/wearable/view/ProgressDrawable.java | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/src/android/support/wearable/view/ProgressDrawable.java b/src/android/support/wearable/view/ProgressDrawable.java new file mode 100644 index 00000000..63e6a039 --- /dev/null +++ b/src/android/support/wearable/view/ProgressDrawable.java @@ -0,0 +1,176 @@ +/* + * Copyright (C) 2015 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License + */ + +package android.support.wearable.view; + +import android.animation.ObjectAnimator; +import android.animation.TimeInterpolator; +import android.animation.ValueAnimator; +import android.annotation.TargetApi; +import android.graphics.Canvas; +import android.graphics.ColorFilter; +import android.graphics.Paint; +import android.graphics.PixelFormat; +import android.graphics.RectF; +import android.graphics.drawable.Drawable; +import android.os.Build; +import android.util.Property; +import android.view.animation.LinearInterpolator; + +/** + * Drawable for showing an indeterminate progress indicator. + * + * TODO: When Material progress drawable is available in the support library stop using this. + * + * @hide + */ +@TargetApi(Build.VERSION_CODES.KITKAT_WATCH) +class ProgressDrawable extends Drawable { + + private static Property<ProgressDrawable, Integer> LEVEL = + new Property<ProgressDrawable, Integer>(Integer.class, "level") { + @Override + public Integer get(ProgressDrawable drawable) { + return drawable.getLevel(); + } + + @Override + public void set(ProgressDrawable drawable, Integer value) { + drawable.setLevel(value); + drawable.invalidateSelf(); + } + }; + /** Max level for a level drawable, as specified in developer docs for {@link Drawable}. */ + private static final int MAX_LEVEL = 10000; + + /** How many different sections are there, five gives us the material style star. **/ + private static final int NUMBER_OF_SEGMENTS = 5; + + private static final int LEVELS_PER_SEGMENT = MAX_LEVEL / NUMBER_OF_SEGMENTS; + private static final float STARTING_ANGLE = -90f; + private static final long ANIMATION_DURATION = 6000; + private static final int FULL_CIRCLE = 360; + private static final int MAX_SWEEP = 306; + private static final int CORRECTION_ANGLE = FULL_CIRCLE - MAX_SWEEP; + /** How far through each cycle does the bar stop growing and start shrinking, half way. **/ + private static final float GROW_SHRINK_RATIO = 0.5f; + // TODO: replace this with BakedBezierInterpolator when its available in support library. + private static final TimeInterpolator mInterpolator = Gusterpolator.INSTANCE; + + private final RectF mInnerCircleBounds = new RectF(); + private final Paint mPaint = new Paint(); + private final ObjectAnimator mAnimator; + private float mCircleBorderWidth; + private int mCircleBorderColor; + + public ProgressDrawable() { + mPaint.setAntiAlias(true); + mPaint.setStyle(Paint.Style.STROKE); + mAnimator = ObjectAnimator.ofInt(this, LEVEL, 0, MAX_LEVEL); + mAnimator.setRepeatCount(ValueAnimator.INFINITE); + mAnimator.setRepeatMode(ValueAnimator.RESTART); + mAnimator.setDuration(ANIMATION_DURATION); + mAnimator.setInterpolator(new LinearInterpolator()); + } + + public void setRingColor(int color) { + mCircleBorderColor = color; + } + + public void setRingWidth(float width) { + mCircleBorderWidth = width; + } + + public void startAnimation() { + mAnimator.start(); + } + + public void stopAnimation() { + mAnimator.cancel(); + } + + @Override + public void draw(Canvas canvas) { + canvas.save(); + mInnerCircleBounds.set(getBounds()); + mInnerCircleBounds.inset(mCircleBorderWidth / 2.0f, mCircleBorderWidth / 2.0f); + mPaint.setStrokeWidth(mCircleBorderWidth); + mPaint.setColor(mCircleBorderColor); + + float sweepAngle = FULL_CIRCLE; + boolean growing = false; + float correctionAngle = 0; + int level = getLevel(); + + int currentSegment = level / LEVELS_PER_SEGMENT; + int offset = currentSegment * LEVELS_PER_SEGMENT; + float progress = (level - offset) / (float) LEVELS_PER_SEGMENT; + + growing = progress < GROW_SHRINK_RATIO; + correctionAngle = CORRECTION_ANGLE * progress; + + if (growing) { + sweepAngle = MAX_SWEEP * mInterpolator.getInterpolation( + lerpInv(0f, GROW_SHRINK_RATIO, progress)); + } else { + sweepAngle = MAX_SWEEP * (1.0f - mInterpolator.getInterpolation( + lerpInv(GROW_SHRINK_RATIO, 1.0f, progress))); + } + + sweepAngle = Math.max(1, sweepAngle); + + canvas.rotate( + level * (1.0f / MAX_LEVEL) * 2 * FULL_CIRCLE + STARTING_ANGLE + correctionAngle, + mInnerCircleBounds.centerX(), + mInnerCircleBounds.centerY()); + canvas.drawArc(mInnerCircleBounds, + growing ? 0 : MAX_SWEEP - sweepAngle, + sweepAngle, + false, + mPaint); + canvas.restore(); + } + + @Override + public void setAlpha(int i) { + // Not supported. + } + + @Override + public void setColorFilter(ColorFilter colorFilter) { + // Not supported. + } + + @Override + public int getOpacity() { + return PixelFormat.OPAQUE; + } + + @Override + protected boolean onLevelChange(int level) { + return true; // Changing the level of this drawable does change its appearance. + } + + /** + * Returns the interpolation scalar (s) that satisfies the equation: + * {@code value = }lerp(a, b, s) + * + * <p>If {@code a == b}, then this function will return 0. + */ + private static float lerpInv(float a, float b, float value) { + return a != b ? ((value - a) / (b - a)) : 0.0f; + } +} |