/*
* Copyright (C) 2015 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.setupwizardlib.view;
import android.annotation.TargetApi;
import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.os.Build.VERSION;
import android.os.Build.VERSION_CODES;
import android.util.AttributeSet;
import android.util.LayoutDirection;
import android.view.Gravity;
import android.view.ViewOutlineProvider;
import android.widget.FrameLayout;
import com.android.setupwizardlib.R;
/**
* Class to draw the illustration of setup wizard. The aspectRatio attribute determines the aspect
* ratio of the top padding, which is leaving space for the illustration. Draws an illustration
* (foreground) to fit the width of the view and fills the rest with the background.
*
* If an aspect ratio is set, then the aspect ratio of the source drawable is maintained. Otherwise
* the the aspect ratio will be ignored, only increasing the width of the illustration.
*/
public class Illustration extends FrameLayout {
// Size of the baseline grid in pixels
private float mBaselineGridSize;
private Drawable mBackground;
private Drawable mIllustration;
private final Rect mViewBounds = new Rect();
private final Rect mIllustrationBounds = new Rect();
private float mScale = 1.0f;
private float mAspectRatio = 0.0f;
public Illustration(Context context) {
super(context);
init(null, 0);
}
public Illustration(Context context, AttributeSet attrs) {
super(context, attrs);
init(attrs, 0);
}
@TargetApi(VERSION_CODES.HONEYCOMB)
public Illustration(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init(attrs, defStyleAttr);
}
// All the constructors delegate to this init method. The 3-argument constructor is not
// available in FrameLayout before v11, so call super with the exact same arguments.
private void init(AttributeSet attrs, int defStyleAttr) {
if (attrs != null) {
TypedArray a = getContext().obtainStyledAttributes(attrs,
R.styleable.SuwIllustration, defStyleAttr, 0);
mAspectRatio = a.getFloat(R.styleable.SuwIllustration_suwAspectRatio, 0.0f);
a.recycle();
}
// Number of pixels of the 8dp baseline grid as defined in material design specs
mBaselineGridSize = getResources().getDisplayMetrics().density * 8;
setWillNotDraw(false);
}
/**
* The background will be drawn to fill up the rest of the view. It will also be scaled by the
* same amount as the foreground so their textures look the same.
*/
// Override the deprecated setBackgroundDrawable method to support API < 16. View.setBackground
// forwards to setBackgroundDrawable in the framework implementation.
@SuppressWarnings("deprecation")
@Override
public void setBackgroundDrawable(Drawable background) {
if (background == mBackground) {
return;
}
mBackground = background;
invalidate();
requestLayout();
}
/**
* Sets the drawable used as the illustration. The drawable is expected to have intrinsic
* width and height defined and will be scaled to fit the width of the view.
*/
public void setIllustration(Drawable illustration) {
if (illustration == mIllustration) {
return;
}
mIllustration = illustration;
invalidate();
requestLayout();
}
/**
* Set the aspect ratio reserved for the illustration. This overrides the top padding of the
* view according to the width of this view and the aspect ratio. Children views will start
* being laid out below this aspect ratio.
*
* @param aspectRatio A float value specifying the aspect ratio (= width / height). 0 to not
* override the top padding.
*/
public void setAspectRatio(float aspectRatio) {
mAspectRatio = aspectRatio;
invalidate();
requestLayout();
}
@Override
@Deprecated
public void setForeground(Drawable d) {
setIllustration(d);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mAspectRatio != 0.0f) {
int parentWidth = MeasureSpec.getSize(widthMeasureSpec);
int illustrationHeight = (int) (parentWidth / mAspectRatio);
illustrationHeight -= illustrationHeight % mBaselineGridSize;
setPadding(0, illustrationHeight, 0, 0);
}
if (VERSION.SDK_INT >= VERSION_CODES.LOLLIPOP) {
setOutlineProvider(ViewOutlineProvider.BOUNDS);
}
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
final int layoutWidth = right - left;
final int layoutHeight = bottom - top;
if (mIllustration != null) {
int intrinsicWidth = mIllustration.getIntrinsicWidth();
int intrinsicHeight = mIllustration.getIntrinsicHeight();
mViewBounds.set(0, 0, layoutWidth, layoutHeight);
if (mAspectRatio != 0f) {
mScale = layoutWidth / (float) intrinsicWidth;
intrinsicWidth = layoutWidth;
intrinsicHeight = (int) (intrinsicHeight * mScale);
}
Gravity.apply(Gravity.FILL_HORIZONTAL | Gravity.TOP, intrinsicWidth,
intrinsicHeight, mViewBounds, mIllustrationBounds);
mIllustration.setBounds(mIllustrationBounds);
}
if (mBackground != null) {
// Scale the background bounds by the same scale to compensate for the scale done to the
// canvas in onDraw.
mBackground.setBounds(0, 0, (int) Math.ceil(layoutWidth / mScale),
(int) Math.ceil((layoutHeight - mIllustrationBounds.height()) / mScale));
}
super.onLayout(changed, left, top, right, bottom);
}
@Override
public void onDraw(Canvas canvas) {
if (mBackground != null) {
// Draw the background filling parts not covered by the illustration
canvas.save();
canvas.translate(0, mIllustrationBounds.height());
// Scale the background so its size matches the foreground
canvas.scale(mScale, mScale, 0, 0);
if (VERSION.SDK_INT > VERSION_CODES.JELLY_BEAN_MR1 &&
shouldMirrorDrawable(mBackground, getLayoutDirection())) {
// Flip the illustration for RTL layouts
canvas.scale(-1, 1);
canvas.translate(-mBackground.getBounds().width(), 0);
}
mBackground.draw(canvas);
canvas.restore();
}
if (mIllustration != null) {
canvas.save();
if (VERSION.SDK_INT > VERSION_CODES.JELLY_BEAN_MR1 &&
shouldMirrorDrawable(mIllustration, getLayoutDirection())) {
// Flip the illustration for RTL layouts
canvas.scale(-1, 1);
canvas.translate(-mIllustrationBounds.width(), 0);
}
// Draw the illustration
mIllustration.draw(canvas);
canvas.restore();
}
super.onDraw(canvas);
}
private boolean shouldMirrorDrawable(Drawable drawable, int layoutDirection) {
if (layoutDirection == LayoutDirection.RTL) {
if (VERSION.SDK_INT >= VERSION_CODES.KITKAT) {
return drawable.isAutoMirrored();
} else if (VERSION.SDK_INT >= VERSION_CODES.JELLY_BEAN_MR1) {
final int flags = getContext().getApplicationInfo().flags;
return (flags & ApplicationInfo.FLAG_SUPPORTS_RTL) != 0;
}
}
return false;
}
}