1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License
15 */
16
17package com.android.systemui.statusbar;
18
19import android.animation.Animator;
20import android.animation.AnimatorListenerAdapter;
21import android.animation.ValueAnimator;
22import android.content.Context;
23import android.graphics.Canvas;
24import android.graphics.Color;
25import android.graphics.Paint;
26import android.graphics.PorterDuff;
27import android.graphics.PorterDuffXfermode;
28import android.graphics.Rect;
29import android.util.AttributeSet;
30import android.view.View;
31import android.view.animation.Interpolator;
32
33/**
34 * A view which can draw a scrim
35 */
36public class ScrimView extends View
37{
38    private final Paint mPaint = new Paint();
39    private int mScrimColor;
40    private boolean mIsEmpty = true;
41    private boolean mDrawAsSrc;
42    private float mViewAlpha = 1.0f;
43    private ValueAnimator mAlphaAnimator;
44    private Rect mExcludedRect = new Rect();
45    private boolean mHasExcludedArea;
46    private ValueAnimator.AnimatorUpdateListener mAlphaUpdateListener
47            = new ValueAnimator.AnimatorUpdateListener() {
48        @Override
49        public void onAnimationUpdate(ValueAnimator animation) {
50            mViewAlpha = (float) animation.getAnimatedValue();
51            invalidate();
52        }
53    };
54    private AnimatorListenerAdapter mClearAnimatorListener = new AnimatorListenerAdapter() {
55        @Override
56        public void onAnimationEnd(Animator animation) {
57            mAlphaAnimator = null;
58        }
59    };
60    private Runnable mChangeRunnable;
61
62    public ScrimView(Context context) {
63        this(context, null);
64    }
65
66    public ScrimView(Context context, AttributeSet attrs) {
67        this(context, attrs, 0);
68    }
69
70    public ScrimView(Context context, AttributeSet attrs, int defStyleAttr) {
71        this(context, attrs, defStyleAttr, 0);
72    }
73
74    public ScrimView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
75        super(context, attrs, defStyleAttr, defStyleRes);
76    }
77
78    @Override
79    protected void onDraw(Canvas canvas) {
80        if (mDrawAsSrc || (!mIsEmpty && mViewAlpha > 0f)) {
81            PorterDuff.Mode mode = mDrawAsSrc ? PorterDuff.Mode.SRC : PorterDuff.Mode.SRC_OVER;
82            int color = getScrimColorWithAlpha();
83            if (!mHasExcludedArea) {
84                canvas.drawColor(color, mode);
85            } else {
86                mPaint.setColor(color);
87                if (mExcludedRect.top > 0) {
88                    canvas.drawRect(0, 0, getWidth(), mExcludedRect.top, mPaint);
89                }
90                if (mExcludedRect.left > 0) {
91                    canvas.drawRect(0,  mExcludedRect.top, mExcludedRect.left, mExcludedRect.bottom,
92                            mPaint);
93                }
94                if (mExcludedRect.right < getWidth()) {
95                    canvas.drawRect(mExcludedRect.right,
96                            mExcludedRect.top,
97                            getWidth(),
98                            mExcludedRect.bottom,
99                            mPaint);
100                }
101                if (mExcludedRect.bottom < getHeight()) {
102                    canvas.drawRect(0,  mExcludedRect.bottom, getWidth(), getHeight(), mPaint);
103                }
104            }
105        }
106    }
107
108    public int getScrimColorWithAlpha() {
109        int color = mScrimColor;
110        color = Color.argb((int) (Color.alpha(color) * mViewAlpha), Color.red(color),
111                Color.green(color), Color.blue(color));
112        return color;
113    }
114
115    public void setDrawAsSrc(boolean asSrc) {
116        mDrawAsSrc = asSrc;
117        mPaint.setXfermode(new PorterDuffXfermode(mDrawAsSrc ? PorterDuff.Mode.SRC
118                : PorterDuff.Mode.SRC_OVER));
119        invalidate();
120    }
121
122    public void setScrimColor(int color) {
123        if (color != mScrimColor) {
124            mIsEmpty = Color.alpha(color) == 0;
125            mScrimColor = color;
126            invalidate();
127            if (mChangeRunnable != null) {
128                mChangeRunnable.run();
129            }
130        }
131    }
132
133    public int getScrimColor() {
134        return mScrimColor;
135    }
136
137    @Override
138    public boolean hasOverlappingRendering() {
139        return false;
140    }
141
142    public void setViewAlpha(float alpha) {
143        if (mAlphaAnimator != null) {
144            mAlphaAnimator.cancel();
145        }
146        if (alpha != mViewAlpha) {
147            mViewAlpha = alpha;
148            invalidate();
149            if (mChangeRunnable != null) {
150                mChangeRunnable.run();
151            }
152        }
153    }
154
155    public void animateViewAlpha(float alpha, long durationOut, Interpolator interpolator) {
156        if (mAlphaAnimator != null) {
157            mAlphaAnimator.cancel();
158        }
159        mAlphaAnimator = ValueAnimator.ofFloat(mViewAlpha, alpha);
160        mAlphaAnimator.addUpdateListener(mAlphaUpdateListener);
161        mAlphaAnimator.addListener(mClearAnimatorListener);
162        mAlphaAnimator.setInterpolator(interpolator);
163        mAlphaAnimator.setDuration(durationOut);
164        mAlphaAnimator.start();
165    }
166
167    public void setExcludedArea(Rect area) {
168        if (area == null) {
169            mHasExcludedArea = false;
170            invalidate();
171            return;
172        }
173
174        int left = Math.max(area.left, 0);
175        int top = Math.max(area.top, 0);
176        int right = Math.min(area.right, getWidth());
177        int bottom = Math.min(area.bottom, getHeight());
178        mExcludedRect.set(left, top, right, bottom);
179        mHasExcludedArea = left < right && top < bottom;
180        invalidate();
181    }
182
183    public void setChangeRunnable(Runnable changeRunnable) {
184        mChangeRunnable = changeRunnable;
185    }
186}
187