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.content.res.TypedArray;
24import android.graphics.Canvas;
25import android.graphics.Color;
26import android.graphics.Paint;
27import android.graphics.PorterDuff;
28import android.graphics.PorterDuffXfermode;
29import android.graphics.Rect;
30import android.util.AttributeSet;
31import android.view.View;
32import android.view.animation.Interpolator;
33import com.android.systemui.R;
34
35/**
36 * A view which can draw a scrim
37 */
38public class ScrimView extends View
39{
40    private final Paint mPaint = new Paint();
41    private int mScrimColor;
42    private boolean mIsEmpty = true;
43    private boolean mDrawAsSrc;
44    private float mViewAlpha = 1.0f;
45    private ValueAnimator mAlphaAnimator;
46    private Rect mExcludedRect = new Rect();
47    private boolean mHasExcludedArea;
48    private ValueAnimator.AnimatorUpdateListener mAlphaUpdateListener
49            = new ValueAnimator.AnimatorUpdateListener() {
50        @Override
51        public void onAnimationUpdate(ValueAnimator animation) {
52            mViewAlpha = (float) animation.getAnimatedValue();
53            invalidate();
54        }
55    };
56    private AnimatorListenerAdapter mClearAnimatorListener = new AnimatorListenerAdapter() {
57        @Override
58        public void onAnimationEnd(Animator animation) {
59            mAlphaAnimator = null;
60        }
61    };
62    private Runnable mChangeRunnable;
63
64    public ScrimView(Context context) {
65        this(context, null);
66    }
67
68    public ScrimView(Context context, AttributeSet attrs) {
69        this(context, attrs, 0);
70    }
71
72    public ScrimView(Context context, AttributeSet attrs, int defStyleAttr) {
73        this(context, attrs, defStyleAttr, 0);
74    }
75
76    public ScrimView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
77        super(context, attrs, defStyleAttr, defStyleRes);
78
79        TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.ScrimView);
80
81        try {
82            mScrimColor = ta.getColor(R.styleable.ScrimView_scrimColor, Color.BLACK);
83        } finally {
84            ta.recycle();
85        }
86    }
87
88    @Override
89    protected void onDraw(Canvas canvas) {
90        if (mDrawAsSrc || (!mIsEmpty && mViewAlpha > 0f)) {
91            PorterDuff.Mode mode = mDrawAsSrc ? PorterDuff.Mode.SRC : PorterDuff.Mode.SRC_OVER;
92            int color = getScrimColorWithAlpha();
93            if (!mHasExcludedArea) {
94                canvas.drawColor(color, mode);
95            } else {
96                mPaint.setColor(color);
97                if (mExcludedRect.top > 0) {
98                    canvas.drawRect(0, 0, getWidth(), mExcludedRect.top, mPaint);
99                }
100                if (mExcludedRect.left > 0) {
101                    canvas.drawRect(0,  mExcludedRect.top, mExcludedRect.left, mExcludedRect.bottom,
102                            mPaint);
103                }
104                if (mExcludedRect.right < getWidth()) {
105                    canvas.drawRect(mExcludedRect.right,
106                            mExcludedRect.top,
107                            getWidth(),
108                            mExcludedRect.bottom,
109                            mPaint);
110                }
111                if (mExcludedRect.bottom < getHeight()) {
112                    canvas.drawRect(0,  mExcludedRect.bottom, getWidth(), getHeight(), mPaint);
113                }
114            }
115        }
116    }
117
118    public int getScrimColorWithAlpha() {
119        int color = mScrimColor;
120        color = Color.argb((int) (Color.alpha(color) * mViewAlpha), Color.red(color),
121                Color.green(color), Color.blue(color));
122        return color;
123    }
124
125    public void setDrawAsSrc(boolean asSrc) {
126        mDrawAsSrc = asSrc;
127        mPaint.setXfermode(new PorterDuffXfermode(mDrawAsSrc ? PorterDuff.Mode.SRC
128                : PorterDuff.Mode.SRC_OVER));
129        invalidate();
130    }
131
132    public void setScrimColor(int color) {
133        if (color != mScrimColor) {
134            mIsEmpty = Color.alpha(color) == 0;
135            mScrimColor = color;
136            invalidate();
137            if (mChangeRunnable != null) {
138                mChangeRunnable.run();
139            }
140        }
141    }
142
143    public int getScrimColor() {
144        return mScrimColor;
145    }
146
147    @Override
148    public boolean hasOverlappingRendering() {
149        return false;
150    }
151
152    public void setViewAlpha(float alpha) {
153        if (mAlphaAnimator != null) {
154            mAlphaAnimator.cancel();
155        }
156        if (alpha != mViewAlpha) {
157            mViewAlpha = alpha;
158            invalidate();
159            if (mChangeRunnable != null) {
160                mChangeRunnable.run();
161            }
162        }
163    }
164
165    public void animateViewAlpha(float alpha, long durationOut, Interpolator interpolator) {
166        if (mAlphaAnimator != null) {
167            mAlphaAnimator.cancel();
168        }
169        mAlphaAnimator = ValueAnimator.ofFloat(mViewAlpha, alpha);
170        mAlphaAnimator.addUpdateListener(mAlphaUpdateListener);
171        mAlphaAnimator.addListener(mClearAnimatorListener);
172        mAlphaAnimator.setInterpolator(interpolator);
173        mAlphaAnimator.setDuration(durationOut);
174        mAlphaAnimator.start();
175    }
176
177    public void setExcludedArea(Rect area) {
178        if (area == null) {
179            mHasExcludedArea = false;
180            invalidate();
181            return;
182        }
183
184        int left = Math.max(area.left, 0);
185        int top = Math.max(area.top, 0);
186        int right = Math.min(area.right, getWidth());
187        int bottom = Math.min(area.bottom, getHeight());
188        mExcludedRect.set(left, top, right, bottom);
189        mHasExcludedArea = left < right && top < bottom;
190        invalidate();
191    }
192
193    public void setChangeRunnable(Runnable changeRunnable) {
194        mChangeRunnable = changeRunnable;
195    }
196}
197