gecko/mobile/android/base/LightweightTheme.java

357 lines
13 KiB
Java

/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
package org.mozilla.gecko;
import java.util.ArrayList;
import java.util.List;
import org.json.JSONObject;
import org.mozilla.gecko.AppConstants.Versions;
import org.mozilla.gecko.gfx.BitmapUtils;
import org.mozilla.gecko.util.GeckoEventListener;
import org.mozilla.gecko.util.ThreadUtils;
import org.mozilla.gecko.util.ThreadUtils.AssertBehavior;
import android.app.Application;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.Shader;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Handler;
import android.os.Looper;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.Gravity;
import android.view.View;
import android.view.ViewParent;
public class LightweightTheme implements GeckoEventListener {
private static final String LOGTAG = "GeckoLightweightTheme";
private final Application mApplication;
/* inner-access */ final Handler mHandler;
private Bitmap mBitmap;
private int mColor;
private boolean mIsLight;
public static interface OnChangeListener {
// The View should change its background/text color.
public void onLightweightThemeChanged();
// The View should reset to its default background/text color.
public void onLightweightThemeReset();
}
private final List<OnChangeListener> mListeners;
public LightweightTheme(Application application) {
mApplication = application;
mHandler = new Handler(Looper.getMainLooper());
mListeners = new ArrayList<OnChangeListener>();
// unregister isn't needed as the lifetime is same as the application.
EventDispatcher.getInstance().registerGeckoThreadListener(this,
"LightweightTheme:Update",
"LightweightTheme:Disable");
}
public void addListener(final OnChangeListener listener) {
// Don't inform the listeners that attached late.
// Their onLayout() will take care of them before their onDraw();
mListeners.add(listener);
}
public void removeListener(OnChangeListener listener) {
mListeners.remove(listener);
}
@Override
public void handleMessage(String event, JSONObject message) {
try {
if (event.equals("LightweightTheme:Update")) {
JSONObject lightweightTheme = message.getJSONObject("data");
final String headerURL = lightweightTheme.getString("headerURL");
// Move any heavy lifting off the Gecko thread
ThreadUtils.postToBackgroundThread(new Runnable() {
@Override
public void run() {
String croppedURL = headerURL;
int mark = croppedURL.indexOf('?');
if (mark != -1)
croppedURL = croppedURL.substring(0, mark);
// Get the image and convert it to a bitmap.
final Bitmap bitmap = BitmapUtils.decodeUrl(croppedURL);
mHandler.post(new Runnable() {
@Override
public void run() {
setLightweightTheme(bitmap);
}
});
}
});
} else if (event.equals("LightweightTheme:Disable")) {
mHandler.post(new Runnable() {
@Override
public void run() {
resetLightweightTheme();
}
});
}
} catch (Exception e) {
Log.e(LOGTAG, "Exception handling message \"" + event + "\":", e);
}
}
/**
* Set a new lightweight theme with the given bitmap.
* Note: This should be called on the UI thread to restrict accessing the
* bitmap to a single thread.
*
* @param bitmap The bitmap used for the lightweight theme.
*/
private void setLightweightTheme(Bitmap bitmap) {
if (bitmap == null || bitmap.getWidth() == 0 || bitmap.getHeight() == 0) {
mBitmap = null;
return;
}
// To find the dominant color only once, take the bottom 25% of pixels.
DisplayMetrics dm = mApplication.getResources().getDisplayMetrics();
int maxWidth = Math.max(dm.widthPixels, dm.heightPixels);
int height = (int) (bitmap.getHeight() * 0.25);
// The lightweight theme image's width and height.
int bitmapWidth = bitmap.getWidth();
int bitmapHeight = bitmap.getHeight();
// A cropped bitmap of the bottom 25% of pixels.
Bitmap cropped = Bitmap.createBitmap(bitmap,
bitmapWidth > maxWidth ? bitmapWidth - maxWidth : 0,
bitmapHeight - height,
bitmapWidth > maxWidth ? maxWidth : bitmapWidth,
height);
// Dominant color based on the cropped bitmap.
mColor = BitmapUtils.getDominantColor(cropped, false);
// Calculate the luminance to determine if it's a light or a dark theme.
double luminance = (0.2125 * ((mColor & 0x00FF0000) >> 16)) +
(0.7154 * ((mColor & 0x0000FF00) >> 8)) +
(0.0721 * (mColor &0x000000FF));
mIsLight = luminance > 110;
// The bitmap image might be smaller than the device's width.
// If it's smaller, fill the extra space on the left with the dominant color.
if (bitmap.getWidth() >= maxWidth) {
mBitmap = bitmap;
} else {
Paint paint = new Paint();
paint.setAntiAlias(true);
// Create a bigger image that can fill the device width.
// By creating a canvas for the bitmap, anything drawn on the canvas
// will be drawn on the bitmap.
mBitmap = Bitmap.createBitmap(maxWidth, bitmapHeight, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(mBitmap);
// Fill the canvas with dominant color.
canvas.drawColor(mColor);
// The image should be top-right aligned.
Rect rect = new Rect();
Gravity.apply(Gravity.TOP | Gravity.RIGHT,
bitmapWidth,
bitmapHeight,
new Rect(0, 0, maxWidth, bitmapHeight),
rect);
// Draw the bitmap.
canvas.drawBitmap(bitmap, null, rect, paint);
}
for (OnChangeListener listener : mListeners)
listener.onLightweightThemeChanged();
}
/**
* Reset the lightweight theme.
* Note: This should be called on the UI thread to restrict accessing the
* bitmap to a single thread.
*/
private void resetLightweightTheme() {
ThreadUtils.assertOnUiThread(AssertBehavior.NONE);
if (mBitmap == null) {
return;
}
// Reset the bitmap.
mBitmap = null;
for (OnChangeListener listener : mListeners) {
listener.onLightweightThemeReset();
}
}
/**
* A lightweight theme is enabled only if there is an active bitmap.
*
* @return True if the theme is enabled.
*/
public boolean isEnabled() {
return (mBitmap != null);
}
/**
* Based on the luminance of the domanint color, a theme is classified as light or dark.
*
* @return True if the theme is light.
*/
public boolean isLightTheme() {
return mIsLight;
}
/**
* Crop the image based on the position of the view on the window.
* Either the View or one of its ancestors might have scrolled or translated.
* This value should be taken into account while mapping the View to the Bitmap.
*
* @param view The view requesting a cropped bitmap.
*/
private Bitmap getCroppedBitmap(View view) {
if (mBitmap == null || view == null) {
return null;
}
// Get the global position of the view on the entire screen.
Rect rect = new Rect();
view.getGlobalVisibleRect(rect);
// Get the activity's window position. This does an IPC call, may be expensive.
Rect window = new Rect();
view.getWindowVisibleDisplayFrame(window);
// Calculate the coordinates for the cropped bitmap.
int screenWidth = view.getContext().getResources().getDisplayMetrics().widthPixels;
int left = mBitmap.getWidth() - screenWidth + rect.left;
int right = mBitmap.getWidth() - screenWidth + rect.right;
int top = rect.top - window.top;
int bottom = rect.bottom - window.top;
int offsetX = 0;
int offsetY = 0;
// Find if this view or any of its ancestors has been translated or scrolled.
ViewParent parent;
View curView = view;
do {
if (Versions.feature11Plus) {
offsetX += (int) curView.getTranslationX() - curView.getScrollX();
offsetY += (int) curView.getTranslationY() - curView.getScrollY();
} else {
offsetX -= curView.getScrollX();
offsetY -= curView.getScrollY();
}
parent = curView.getParent();
if (parent instanceof View) {
curView = (View) parent;
}
} while(parent instanceof View && parent != null);
// Adjust the coordinates for the offset.
left -= offsetX;
right -= offsetX;
top -= offsetY;
bottom -= offsetY;
// The either the required height may be less than the available image height or more than it.
// If the height required is more, crop only the available portion on the image.
int width = right - left;
int height = (bottom > mBitmap.getHeight() ? mBitmap.getHeight() - top : bottom - top);
// There is a chance that the view is not visible or doesn't fall within the phone's size.
// In this case, 'rect' will have all values as '0'. Hence 'top' and 'bottom' may be negative,
// and createBitmap() will fail.
// The view will get a background in its next layout pass.
try {
return Bitmap.createBitmap(mBitmap, left, top, width, height);
} catch (Exception e) {
return null;
}
}
/**
* Converts the cropped bitmap to a BitmapDrawable and returns the same.
*
* @param view The view for which a background drawable is required.
* @return Either the cropped bitmap as a Drawable or null.
*/
public Drawable getDrawable(View view) {
Bitmap bitmap = getCroppedBitmap(view);
if (bitmap == null) {
return null;
}
BitmapDrawable drawable = new BitmapDrawable(view.getContext().getResources(), bitmap);
drawable.setGravity(Gravity.TOP | Gravity.RIGHT);
drawable.setTileModeXY(Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
return drawable;
}
/**
* Converts the cropped bitmap to a LightweightThemeDrawable, placing it over the dominant color.
*
* @param view The view for which a background drawable is required.
* @return Either the cropped bitmap as a Drawable or null.
*/
public LightweightThemeDrawable getColorDrawable(View view) {
return getColorDrawable(view, mColor, false);
}
/**
* Converts the cropped bitmap to a LightweightThemeDrawable, placing it over the required color.
*
* @param view The view for which a background drawable is required.
* @param color The color over which the drawable should be drawn.
* @return Either the cropped bitmap as a Drawable or null.
*/
public LightweightThemeDrawable getColorDrawable(View view, int color) {
return getColorDrawable(view, color, false);
}
/**
* Converts the cropped bitmap to a LightweightThemeDrawable, placing it over the required color.
*
* @param view The view for which a background drawable is required.
* @param color The color over which the drawable should be drawn.
* @param needsDominantColor A layer of dominant color is needed or not.
* @return Either the cropped bitmap as a Drawable or null.
*/
public LightweightThemeDrawable getColorDrawable(View view, int color, boolean needsDominantColor) {
Bitmap bitmap = getCroppedBitmap(view);
if (bitmap == null) {
return null;
}
LightweightThemeDrawable drawable = new LightweightThemeDrawable(view.getContext().getResources(), bitmap);
if (needsDominantColor) {
drawable.setColorWithFilter(color, (mColor & 0x22FFFFFF));
} else {
drawable.setColor(color);
}
return drawable;
}
}