1 /* 2 * Copyright (C) 2016 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 package com.android.launcher3.pageindicators; 17 18 import android.content.Context; 19 import android.content.res.Resources; 20 import android.graphics.Canvas; 21 import android.graphics.ColorFilter; 22 import android.graphics.Paint; 23 import android.graphics.Path; 24 import android.graphics.PixelFormat; 25 26 import com.android.launcher3.R; 27 import com.android.launcher3.util.Themes; 28 29 import android.graphics.drawable.Drawable; 30 31 public class CaretDrawable extends Drawable { 32 public static final float PROGRESS_CARET_POINTING_UP = -1f; 33 public static final float PROGRESS_CARET_POINTING_DOWN = 1f; 34 public static final float PROGRESS_CARET_NEUTRAL = 0; 35 36 private float mCaretProgress = PROGRESS_CARET_NEUTRAL; 37 38 private Paint mShadowPaint = new Paint(); 39 private Paint mCaretPaint = new Paint(); 40 private Path mPath = new Path(); 41 private final int mCaretSizePx; 42 CaretDrawable(Context context)43 public CaretDrawable(Context context) { 44 final Resources res = context.getResources(); 45 46 final int strokeWidth = res.getDimensionPixelSize(R.dimen.all_apps_caret_stroke_width); 47 final int shadowSpread = res.getDimensionPixelSize(R.dimen.all_apps_caret_shadow_spread); 48 49 mCaretPaint.setColor(res.getColor(R.color.workspace_icon_text_color)); 50 mCaretPaint.setAntiAlias(true); 51 mCaretPaint.setStrokeWidth(strokeWidth); 52 mCaretPaint.setStyle(Paint.Style.STROKE); 53 mCaretPaint.setStrokeCap(Paint.Cap.SQUARE); 54 mCaretPaint.setStrokeJoin(Paint.Join.MITER); 55 56 mShadowPaint.setColor(res.getColor(R.color.default_shadow_color_no_alpha)); 57 mShadowPaint.setAlpha(Themes.getAlpha(context, android.R.attr.spotShadowAlpha)); 58 mShadowPaint.setAntiAlias(true); 59 mShadowPaint.setStrokeWidth(strokeWidth + (shadowSpread * 2)); 60 mShadowPaint.setStyle(Paint.Style.STROKE); 61 mShadowPaint.setStrokeCap(Paint.Cap.ROUND); 62 mShadowPaint.setStrokeJoin(Paint.Join.ROUND); 63 64 mCaretSizePx = res.getDimensionPixelSize(R.dimen.all_apps_caret_size); 65 } 66 67 @Override getIntrinsicHeight()68 public int getIntrinsicHeight() { 69 return mCaretSizePx; 70 } 71 72 @Override getIntrinsicWidth()73 public int getIntrinsicWidth() { 74 return mCaretSizePx; 75 } 76 77 @Override draw(Canvas canvas)78 public void draw(Canvas canvas) { 79 // Assumes caret paint is more important than shadow paint 80 if (Float.compare(mCaretPaint.getAlpha(), 0f) == 0) { 81 return; 82 } 83 84 // Assumes shadow stroke width is larger 85 final float width = getBounds().width() - mShadowPaint.getStrokeWidth(); 86 final float height = getBounds().height() - mShadowPaint.getStrokeWidth(); 87 final float left = getBounds().left + (mShadowPaint.getStrokeWidth() / 2); 88 final float top = getBounds().top + (mShadowPaint.getStrokeWidth() / 2); 89 90 // When the bounds are square, this will result in a caret with a right angle 91 final float verticalInset = (height / 4); 92 final float caretHeight = (height - (verticalInset * 2)); 93 94 mPath.reset(); 95 mPath.moveTo(left, top + caretHeight * (1 - getNormalizedCaretProgress())); 96 mPath.lineTo(left + (width / 2), top + caretHeight * getNormalizedCaretProgress()); 97 mPath.lineTo(left + width, top + caretHeight * (1 - getNormalizedCaretProgress())); 98 99 canvas.drawPath(mPath, mShadowPaint); 100 canvas.drawPath(mPath, mCaretPaint); 101 } 102 103 /** 104 * Sets the caret progress 105 * 106 * @param progress The progress ({@value #PROGRESS_CARET_POINTING_UP} for pointing up, 107 * {@value #PROGRESS_CARET_POINTING_DOWN} for pointing down, {@value #PROGRESS_CARET_NEUTRAL} 108 * for neutral) 109 */ setCaretProgress(float progress)110 public void setCaretProgress(float progress) { 111 mCaretProgress = progress; 112 invalidateSelf(); 113 } 114 115 /** 116 * Returns the caret progress 117 * 118 * @return The progress 119 */ getCaretProgress()120 public float getCaretProgress() { 121 return mCaretProgress; 122 } 123 124 /** 125 * Returns the caret progress normalized to [0..1] 126 * 127 * @return The normalized progress 128 */ getNormalizedCaretProgress()129 public float getNormalizedCaretProgress() { 130 return (mCaretProgress - PROGRESS_CARET_POINTING_UP) / 131 (PROGRESS_CARET_POINTING_DOWN - PROGRESS_CARET_POINTING_UP); 132 } 133 134 @Override getOpacity()135 public int getOpacity() { 136 return PixelFormat.TRANSLUCENT; 137 } 138 139 @Override setAlpha(int alpha)140 public void setAlpha(int alpha) { 141 mCaretPaint.setAlpha(alpha); 142 mShadowPaint.setAlpha(alpha); 143 invalidateSelf(); 144 } 145 146 @Override setColorFilter(ColorFilter cf)147 public void setColorFilter(ColorFilter cf) { 148 // no-op 149 } 150 } 151