Foreground/background network stats pie chart.

Load foreground/background network stats, showing combined in chart
series, and also separated in pie chart.  Padding to match spec,
updated action bar tabs, and limit width for wide devices.  Also
clear UI options for requesting fragments.  Move to action bar
overflow menu instead of custom icon.  Show detail chart data outside
current inspection range.

Bug: 5106163, 5143670, 5163064, 5162671, 5148713, 5129036, 5096626
Change-Id: I548fef209e1f714f70ee6bf7098dbdb881692df4

src/com/android/settings/widget/PieChartView.java

@@ -0,0 +1,202 @@
+/*
+ * Copyright (C) 2011 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.settings.widget;
+
+import android.content.Context;
+import android.content.res.Resources;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.graphics.Paint.Style;
+import android.graphics.Path;
+import android.graphics.Path.Direction;
+import android.graphics.RadialGradient;
+import android.graphics.RectF;
+import android.graphics.Shader.TileMode;
+import android.util.AttributeSet;
+import android.util.Log;
+import android.view.View;
+
+import com.google.common.collect.Lists;
+
+import java.util.ArrayList;
+
+/**
+ * Pie chart with multiple items.
+ */
+public class PieChartView extends View {
+    public static final String TAG = "PieChartView";
+    public static final boolean LOGD = true;
+
+    private ArrayList<Slice> mSlices = Lists.newArrayList();
+
+    private int mOriginAngle;
+
+    private Paint mPaintPrimary = new Paint();
+    private Paint mPaintShadow = new Paint();
+
+    private Path mPathSide = new Path();
+    private Path mPathSideShadow = new Path();
+
+    private Path mPathShadow = new Path();
+
+    private int mSideWidth;
+
+    public class Slice {
+        public long value;
+
+        public Path pathPrimary = new Path();
+        public Path pathShadow = new Path();
+
+        public Paint paintPrimary;
+
+        public Slice(long value, int color) {
+            this.value = value;
+            this.paintPrimary = buildFillPaint(color, getResources());
+        }
+    }
+
+    public PieChartView(Context context) {
+        this(context, null);
+    }
+
+    public PieChartView(Context context, AttributeSet attrs) {
+        this(context, attrs, 0);
+    }
+
+    public PieChartView(Context context, AttributeSet attrs, int defStyle) {
+        super(context, attrs, defStyle);
+
+        mPaintPrimary = buildFillPaint(Color.parseColor("#666666"), getResources());
+
+        mPaintShadow.setColor(Color.BLACK);
+        mPaintShadow.setStyle(Style.STROKE);
+        mPaintShadow.setStrokeWidth(3f * getResources().getDisplayMetrics().density);
+        mPaintShadow.setAntiAlias(true);
+
+        mSideWidth = (int) (20 * getResources().getDisplayMetrics().density);
+
+        setWillNotDraw(false);
+    }
+
+    private static Paint buildFillPaint(int color, Resources res) {
+        final Paint paint = new Paint();
+
+        paint.setColor(color);
+        paint.setStyle(Style.FILL_AND_STROKE);
+        paint.setAntiAlias(true);
+
+        final int width = (int) (280 * res.getDisplayMetrics().density);
+        paint.setShader(new RadialGradient(0, 0, width, color, darken(color), TileMode.MIRROR));
+
+        return paint;
+    }
+
+    public void setOriginAngle(int originAngle) {
+        mOriginAngle = originAngle;
+    }
+
+    public void addSlice(long value, int color) {
+        mSlices.add(new Slice(value, color));
+    }
+
+    public void removeAllSlices() {
+        mSlices.clear();
+    }
+
+    @Override
+    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
+        generatePath();
+    }
+
+    public void generatePath() {
+        if (LOGD) Log.d(TAG, "generatePath()");
+
+        long total = 0;
+        for (Slice slice : mSlices) {
+            slice.pathPrimary.reset();
+            slice.pathShadow.reset();
+            total += slice.value;
+        }
+
+        mPathSide.reset();
+        mPathSideShadow.reset();
+        mPathShadow.reset();
+
+        // bail when not enough stats to render
+        if (total == 0) {
+            invalidate();
+            return;
+        }
+
+        final int width = getWidth();
+        final int height = getHeight();
+
+        final RectF rect = new RectF(0, 0, width, height);
+
+        mPathSide.addOval(rect, Direction.CW);
+        mPathSideShadow.addOval(rect, Direction.CW);
+        mPathShadow.addOval(rect, Direction.CW);
+
+        int startAngle = mOriginAngle;
+        for (Slice slice : mSlices) {
+            final int sweepAngle = (int) (slice.value * 360 / total);
+
+            slice.pathPrimary.moveTo(rect.centerX(), rect.centerY());
+            slice.pathPrimary.arcTo(rect, startAngle, sweepAngle);
+            slice.pathPrimary.lineTo(rect.centerX(), rect.centerY());
+
+            slice.pathShadow.moveTo(rect.centerX(), rect.centerY());
+            slice.pathShadow.arcTo(rect, startAngle, 0);
+            slice.pathShadow.moveTo(rect.centerX(), rect.centerY());
+            slice.pathShadow.arcTo(rect, startAngle + sweepAngle, 0);
+
+            startAngle += sweepAngle;
+        }
+
+        invalidate();
+    }
+
+    @Override
+    protected void onDraw(Canvas canvas) {
+
+        canvas.translate(getWidth() * 0.25f, getHeight() * -0.05f);
+        canvas.rotate(-40, getWidth() * 0.5f, getHeight());
+        canvas.scale(0.7f, 1.0f, getWidth(), getHeight());
+
+        canvas.save();
+        canvas.translate(-mSideWidth, 0);
+        canvas.drawPath(mPathSide, mPaintPrimary);
+        canvas.drawPath(mPathSideShadow, mPaintShadow);
+        canvas.restore();
+
+        for (Slice slice : mSlices) {
+            canvas.drawPath(slice.pathPrimary, slice.paintPrimary);
+            canvas.drawPath(slice.pathShadow, mPaintShadow);
+        }
+        canvas.drawPath(mPathShadow, mPaintShadow);
+    }
+
+    public static int darken(int color) {
+        float[] hsv = new float[3];
+        Color.colorToHSV(color, hsv);
+        hsv[2] /= 2;
+        hsv[1] /= 2;
+        return Color.HSVToColor(hsv);
+    }
+
+}