SetupWizardIllustration.java revision 62c15e38d1b7555b4b854b4de6f9d9ae90ecdb65 
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
17
18package com.android.settings.widget;
19
20import android.content.Context;
21import android.content.res.TypedArray;
22import android.graphics.Canvas;
23import android.graphics.Rect;
24import android.graphics.drawable.Drawable;
25import android.util.AttributeSet;
26import android.util.Log;
27import android.view.Gravity;
28import android.widget.FrameLayout;
29
30import com.android.settings.R;
31
32/**
33 * Class to draw the illustration of setup wizard. The aspectRatio attribute determines the aspect
34 * ratio of the top padding, which is leaving space for the illustration. Draws an illustration
35 * (foreground) to fit the width of the view and fills the rest with the background.
36 *
37 * Copied from com.google.android.setupwizard.util.SetupWizardIllustration
38 */
39public class SetupWizardIllustration extends FrameLayout {
40
41    private static final String TAG = "SetupWizardIllustration";
42
43    // Size of the baseline grid in pixels
44    private float mBaselineGridSize;
45    private Drawable mBackground;
46    private Drawable mForeground;
47    private final Rect mViewBounds = new Rect();
48    private final Rect mForegroundBounds = new Rect();
49    private float mScale = 1.0f;
50    private float mAspectRatio = 0.0f;
51
52    public SetupWizardIllustration(Context context) {
53        this(context, null);
54    }
55
56    public SetupWizardIllustration(Context context, AttributeSet attrs) {
57        this(context, attrs, 0);
58    }
59
60    public SetupWizardIllustration(Context context, AttributeSet attrs, int defStyleAttr) {
61        this(context, attrs, defStyleAttr, 0);
62    }
63
64    public SetupWizardIllustration(Context context, AttributeSet attrs, int defStyleAttr,
65            int defStyleRes) {
66        super(context, attrs, defStyleAttr, defStyleRes);
67        if (attrs != null) {
68            TypedArray a = context.obtainStyledAttributes(attrs,
69                    R.styleable.SetupWizardIllustration, 0, 0);
70            mAspectRatio = a.getFloat(R.styleable.SetupWizardIllustration_aspectRatio, 0.0f);
71            a.recycle();
72        }
73        // Number of pixels of the 8dp baseline grid as defined in material design specs
74        mBaselineGridSize = getResources().getDisplayMetrics().density * 8;
75        setWillNotDraw(false);
76    }
77
78    /**
79     * The background will be drawn to fill up the rest of the view. It will also be scaled by the
80     * same amount as the foreground so their textures look the same.
81     */
82    @Override
83    public void setBackground(Drawable background) {
84        mBackground = background;
85    }
86
87    /**
88     * Sets the drawable used as the illustration. THe drawable is expected to have intrinsic
89     * width and height defined and will be scaled to fit the width of the view.
90     */
91    @Override
92    public void setForeground(Drawable foreground) {
93        mForeground = foreground;
94    }
95
96    @Override
97    public void onResolveDrawables(int layoutDirection) {
98        mBackground.setLayoutDirection(layoutDirection);
99        mForeground.setLayoutDirection(layoutDirection);
100    }
101
102    @Override
103    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
104        if (mAspectRatio != 0.0f) {
105            int parentWidth = MeasureSpec.getSize(widthMeasureSpec);
106            int illustrationHeight = (int) (parentWidth / mAspectRatio);
107            illustrationHeight -= illustrationHeight % mBaselineGridSize;
108            setPaddingRelative(0, illustrationHeight, 0, 0);
109        }
110        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
111    }
112
113    @Override
114    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
115        final int layoutWidth = right - left;
116        final int layoutHeight = bottom - top;
117        if (mForeground != null) {
118            int intrinsicWidth = mForeground.getIntrinsicWidth();
119            int intrinsicHeight = mForeground.getIntrinsicHeight();
120            final int layoutDirection = getLayoutDirection();
121
122            mViewBounds.set(0, 0, layoutWidth, layoutHeight);
123            if (mAspectRatio != 0f) {
124                mScale = layoutWidth / (float) intrinsicWidth;
125                intrinsicWidth = layoutWidth;
126                intrinsicHeight = (int) (intrinsicHeight * mScale);
127            }
128            Gravity.apply(Gravity.FILL_HORIZONTAL | Gravity.TOP, intrinsicWidth, intrinsicHeight,
129                    mViewBounds, mForegroundBounds, layoutDirection);
130            mForeground.setBounds(mForegroundBounds);
131        }
132        if (mBackground != null) {
133            // Scale the bounds by mScale to compensate for the scale done to the canvas before
134            // drawing.
135            mBackground.setBounds(0, 0, (int) Math.ceil(layoutWidth / mScale),
136                    (int) Math.ceil((layoutHeight - mForegroundBounds.height()) / mScale));
137        }
138        super.onLayout(changed, left, top, right, bottom);
139    }
140
141    @Override
142    public void onDraw(Canvas canvas) {
143        if (mBackground != null) {
144            canvas.save();
145            // Draw the background filling parts not covered by the illustration
146            canvas.translate(0, mForegroundBounds.height());
147            // Scale the background so its size matches the foreground
148            canvas.scale(mScale, mScale, 0, 0);
149            mBackground.draw(canvas);
150            canvas.restore();
151        }
152        if (mForeground != null) {
153            canvas.save();
154            // Draw the illustration
155            mForeground.draw(canvas);
156            canvas.restore();
157        }
158        super.onDraw(canvas);
159    }
160}
161