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      1 /*
      2  * Copyright (C) 2010 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 
     17 package com.android.settings.deviceinfo;
     18 
     19 import android.content.Context;
     20 import android.content.res.TypedArray;
     21 import android.graphics.Canvas;
     22 import android.graphics.Color;
     23 import android.graphics.Paint;
     24 import android.util.AttributeSet;
     25 import android.view.View;
     26 
     27 import com.android.settings.R;
     28 
     29 import java.util.Collection;
     30 
     31 /**
     32  * Draws a horizontal bar chart with colored slices, each represented by
     33  * {@link Entry}.
     34  */
     35 public class PercentageBarChart extends View {
     36     private final Paint mEmptyPaint = new Paint();
     37 
     38     private Collection<Entry> mEntries;
     39 
     40     private int mMinTickWidth = 1;
     41 
     42     public static class Entry implements Comparable<Entry> {
     43         public final int order;
     44         public final float percentage;
     45         public final Paint paint;
     46 
     47         protected Entry(int order, float percentage, Paint paint) {
     48             this.order = order;
     49             this.percentage = percentage;
     50             this.paint = paint;
     51         }
     52 
     53         @Override
     54         public int compareTo(Entry another) {
     55             return order - another.order;
     56         }
     57     }
     58 
     59     public PercentageBarChart(Context context, AttributeSet attrs) {
     60         super(context, attrs);
     61 
     62         TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.PercentageBarChart);
     63         mMinTickWidth = a.getDimensionPixelSize(R.styleable.PercentageBarChart_minTickWidth, 1);
     64         int emptyColor = a.getColor(R.styleable.PercentageBarChart_emptyColor, Color.BLACK);
     65         a.recycle();
     66 
     67         mEmptyPaint.setColor(emptyColor);
     68         mEmptyPaint.setStyle(Paint.Style.FILL);
     69     }
     70 
     71     @Override
     72     protected void onDraw(Canvas canvas) {
     73         super.onDraw(canvas);
     74 
     75         final int left = getPaddingLeft();
     76         final int right = getWidth() - getPaddingRight();
     77         final int top = getPaddingTop();
     78         final int bottom = getHeight() - getPaddingBottom();
     79 
     80         final int width = right - left;
     81 
     82         final boolean isLayoutRtl = isLayoutRtl();
     83         if (isLayoutRtl) {
     84             float nextX = right;
     85 
     86             if (mEntries != null) {
     87                 for (final Entry e : mEntries) {
     88                     final float entryWidth;
     89                     if (e.percentage == 0.0f) {
     90                         entryWidth = 0.0f;
     91                     } else {
     92                         entryWidth = Math.max(mMinTickWidth, width * e.percentage);
     93                     }
     94 
     95                     final float lastX = nextX - entryWidth;
     96                     if (lastX < left) {
     97                         canvas.drawRect(left, top, nextX, bottom, e.paint);
     98                         return;
     99                     }
    100 
    101                     canvas.drawRect(lastX, top, nextX, bottom, e.paint);
    102                     nextX = lastX;
    103                 }
    104             }
    105 
    106             canvas.drawRect(left, top, nextX, bottom, mEmptyPaint);
    107         } else {
    108             float lastX = left;
    109 
    110             if (mEntries != null) {
    111                 for (final Entry e : mEntries) {
    112                     final float entryWidth;
    113                     if (e.percentage == 0.0f) {
    114                         entryWidth = 0.0f;
    115                     } else {
    116                         entryWidth = Math.max(mMinTickWidth, width * e.percentage);
    117                     }
    118 
    119                     final float nextX = lastX + entryWidth;
    120                     if (nextX > right) {
    121                         canvas.drawRect(lastX, top, right, bottom, e.paint);
    122                         return;
    123                     }
    124 
    125                     canvas.drawRect(lastX, top, nextX, bottom, e.paint);
    126                     lastX = nextX;
    127                 }
    128             }
    129 
    130             canvas.drawRect(lastX, top, right, bottom, mEmptyPaint);
    131         }
    132     }
    133 
    134     /**
    135      * Sets the background for this chart. Callers are responsible for later
    136      * calling {@link #invalidate()}.
    137      */
    138     @Override
    139     public void setBackgroundColor(int color) {
    140         mEmptyPaint.setColor(color);
    141     }
    142 
    143     /**
    144      * Adds a new slice to the percentage bar chart. Callers are responsible for
    145      * later calling {@link #invalidate()}.
    146      *
    147      * @param percentage the total width that
    148      * @param color the color to draw the entry
    149      */
    150     public static Entry createEntry(int order, float percentage, int color) {
    151         final Paint p = new Paint();
    152         p.setColor(color);
    153         p.setStyle(Paint.Style.FILL);
    154         return new Entry(order, percentage, p);
    155     }
    156 
    157     public void setEntries(Collection<Entry> entries) {
    158         mEntries = entries;
    159     }
    160 }
    161