| /* |
| * Copyright (C) 2014 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 com.android.systemui.statusbar.policy; |
| |
| import android.graphics.Canvas; |
| import android.graphics.Color; |
| import android.graphics.ColorFilter; |
| import android.graphics.Paint; |
| import android.graphics.PixelFormat; |
| import android.graphics.RadialGradient; |
| import android.graphics.Rect; |
| import android.graphics.Shader; |
| import android.graphics.drawable.Drawable; |
| import android.util.LayoutDirection; |
| import android.view.View; |
| |
| import com.android.systemui.R; |
| |
| /** |
| * Gradient background for the user switcher on Keyguard. |
| */ |
| public class KeyguardUserSwitcherScrim extends Drawable |
| implements View.OnLayoutChangeListener { |
| |
| private static final float OUTER_EXTENT = 2.5f; |
| private static final float INNER_EXTENT = 0.75f; |
| |
| private int mDarkColor; |
| private int mTop; |
| private int mAlpha = 255; |
| private Paint mRadialGradientPaint = new Paint(); |
| private int mLayoutWidth; |
| |
| public KeyguardUserSwitcherScrim(View host) { |
| host.addOnLayoutChangeListener(this); |
| mDarkColor = host.getContext().getColor( |
| R.color.keyguard_user_switcher_background_gradient_color); |
| } |
| |
| @Override |
| public void draw(Canvas canvas) { |
| boolean isLtr = getLayoutDirection() == LayoutDirection.LTR; |
| Rect bounds = getBounds(); |
| float width = bounds.width() * OUTER_EXTENT; |
| float height = (mTop + bounds.height()) * OUTER_EXTENT; |
| canvas.translate(0, -mTop); |
| canvas.scale(1, height / width); |
| canvas.drawRect(isLtr ? bounds.right - width : 0, 0, |
| isLtr ? bounds.right : bounds.left + width, width, mRadialGradientPaint); |
| } |
| |
| @Override |
| public void setAlpha(int alpha) { |
| mAlpha = alpha; |
| updatePaint(); |
| invalidateSelf(); |
| } |
| |
| @Override |
| public int getAlpha() { |
| return mAlpha; |
| } |
| |
| @Override |
| public void setColorFilter(ColorFilter colorFilter) { |
| } |
| |
| @Override |
| public int getOpacity() { |
| return PixelFormat.TRANSLUCENT; |
| } |
| |
| @Override |
| public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, |
| int oldTop, int oldRight, int oldBottom) { |
| if (left != oldLeft || top != oldTop || right != oldRight || bottom != oldBottom) { |
| mLayoutWidth = right - left; |
| mTop = top; |
| updatePaint(); |
| } |
| } |
| |
| private void updatePaint() { |
| if (mLayoutWidth == 0) { |
| return; |
| } |
| float radius = mLayoutWidth * OUTER_EXTENT; |
| boolean isLtr = getLayoutDirection() == LayoutDirection.LTR; |
| mRadialGradientPaint.setShader( |
| new RadialGradient(isLtr ? mLayoutWidth : 0, 0, radius, |
| new int[] { Color.argb( |
| (int) (Color.alpha(mDarkColor) * mAlpha / 255f), 0, 0, 0), |
| Color.TRANSPARENT }, |
| new float[] { Math.max(0f, mLayoutWidth * INNER_EXTENT / radius), 1f }, |
| Shader.TileMode.CLAMP)); |
| } |
| } |