michael@0: /* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: package org.mozilla.gecko.widget;
michael@0: 
michael@0: import org.mozilla.gecko.R;
michael@0: import org.mozilla.gecko.favicons.Favicons;
michael@0: 
michael@0: import android.content.Context;
michael@0: import android.graphics.Bitmap;
michael@0: import android.graphics.Canvas;
michael@0: import android.graphics.Paint;
michael@0: import android.graphics.RectF;
michael@0: import android.util.AttributeSet;
michael@0: import android.widget.ImageView;
michael@0: /**
michael@0:  * Special version of ImageView for favicons.
michael@0:  * Displays solid colour background around Favicon to fill space not occupied by the icon. Colour
michael@0:  * selected is the dominant colour of the provided Favicon.
michael@0:  */
michael@0: public class FaviconView extends ImageView {
michael@0:     private Bitmap mIconBitmap;
michael@0: 
michael@0:     // Reference to the unscaled bitmap, if any, to prevent repeated assignments of the same bitmap
michael@0:     // to the view from causing repeated rescalings (Some of the callers do this)
michael@0:     private Bitmap mUnscaledBitmap;
michael@0: 
michael@0:     // Key into the Favicon dominant colour cache. Should be the Favicon URL if the image displayed
michael@0:     // here is a Favicon managed by the caching system. If not, any appropriately unique-to-this-image
michael@0:     // string is acceptable.
michael@0:     private String mIconKey;
michael@0: 
michael@0:     private int mActualWidth;
michael@0:     private int mActualHeight;
michael@0: 
michael@0:     // Flag indicating if the most recently assigned image is considered likely to need scaling.
michael@0:     private boolean mScalingExpected;
michael@0: 
michael@0:     // Dominant color of the favicon.
michael@0:     private int mDominantColor;
michael@0: 
michael@0:     // Stroke width for the border.
michael@0:     private static float sStrokeWidth;
michael@0: 
michael@0:     // Paint for drawing the stroke.
michael@0:     private static Paint sStrokePaint;
michael@0: 
michael@0:     // Paint for drawing the background.
michael@0:     private static Paint sBackgroundPaint;
michael@0: 
michael@0:     // Size of the stroke rectangle.
michael@0:     private final RectF mStrokeRect;
michael@0: 
michael@0:     // Size of the background rectangle.
michael@0:     private final RectF mBackgroundRect;
michael@0: 
michael@0:     // Initializing the static paints.
michael@0:     static {
michael@0:         sStrokePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
michael@0:         sStrokePaint.setStyle(Paint.Style.STROKE);
michael@0: 
michael@0:         sBackgroundPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
michael@0:         sBackgroundPaint.setStyle(Paint.Style.FILL);
michael@0:     }
michael@0: 
michael@0:     public FaviconView(Context context, AttributeSet attrs) {
michael@0:         super(context, attrs);
michael@0:         setScaleType(ImageView.ScaleType.CENTER);
michael@0: 
michael@0:         mStrokeRect = new RectF();
michael@0:         mBackgroundRect = new RectF();
michael@0: 
michael@0:         if (sStrokeWidth == 0) {
michael@0:             sStrokeWidth = getResources().getDisplayMetrics().density;
michael@0:             sStrokePaint.setStrokeWidth(sStrokeWidth);
michael@0:         }
michael@0: 
michael@0:         mStrokeRect.left = mStrokeRect.top = sStrokeWidth;
michael@0:         mBackgroundRect.left = mBackgroundRect.top = sStrokeWidth * 2.0f;
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     protected void onSizeChanged(int w, int h, int oldw, int oldh){
michael@0:         super.onSizeChanged(w, h, oldw, oldh);
michael@0: 
michael@0:         // No point rechecking the image if there hasn't really been any change.
michael@0:         if (w == mActualWidth && h == mActualHeight) {
michael@0:             return;
michael@0:         }
michael@0: 
michael@0:         mActualWidth = w;
michael@0:         mActualHeight = h;
michael@0: 
michael@0:         mStrokeRect.right = w - sStrokeWidth;
michael@0:         mStrokeRect.bottom = h - sStrokeWidth;
michael@0:         mBackgroundRect.right = mStrokeRect.right - sStrokeWidth;
michael@0:         mBackgroundRect.bottom = mStrokeRect.bottom - sStrokeWidth;
michael@0: 
michael@0:         formatImage();
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void onDraw(Canvas canvas) {
michael@0:         super.onDraw(canvas);
michael@0: 
michael@0:         // 27.5% transparent dominant color.
michael@0:         sBackgroundPaint.setColor(mDominantColor & 0x46FFFFFF);
michael@0:         canvas.drawRect(mStrokeRect, sBackgroundPaint);
michael@0: 
michael@0:         sStrokePaint.setColor(mDominantColor);
michael@0:         canvas.drawRoundRect(mStrokeRect, sStrokeWidth, sStrokeWidth, sStrokePaint);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Formats the image for display, if the prerequisite data are available. Upscales tiny Favicons to
michael@0:      * normal sized ones, replaces null bitmaps with the default Favicon, and fills all remaining space
michael@0:      * in this view with the coloured background.
michael@0:      */
michael@0:     private void formatImage() {
michael@0:         // If we're called before bitmap is set, or before size is set, show blank.
michael@0:         if (mIconBitmap == null || mActualWidth == 0 || mActualHeight == 0) {
michael@0:             showNoImage();
michael@0:             return;
michael@0:         }
michael@0: 
michael@0:         if (mScalingExpected && mActualWidth != mIconBitmap.getWidth()) {
michael@0:             scaleBitmap();
michael@0:             // Don't scale the image every time something changes.
michael@0:             mScalingExpected = false;
michael@0:         }
michael@0: 
michael@0:         setImageBitmap(mIconBitmap);
michael@0: 
michael@0:         // After scaling, determine if we have empty space around the scaled image which we need to
michael@0:         // fill with the coloured background. If applicable, show it.
michael@0:         // We assume Favicons are still squares and only bother with the background if more than 3px
michael@0:         // of it would be displayed.
michael@0:         if (Math.abs(mIconBitmap.getWidth() - mActualWidth) > 3) {
michael@0:             mDominantColor = Favicons.getFaviconColor(mIconKey);
michael@0:             if (mDominantColor == -1) {
michael@0:                 mDominantColor = 0;
michael@0:             }
michael@0:         } else {
michael@0:             mDominantColor = 0;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     private void scaleBitmap() {
michael@0:         // If the Favicon can be resized to fill the view exactly without an enlargment of more than
michael@0:         // a factor of two, do so.
michael@0:         int doubledSize = mIconBitmap.getWidth()*2;
michael@0:         if (mActualWidth > doubledSize) {
michael@0:             // If the view is more than twice the size of the image, just double the image size
michael@0:             // and do the rest with padding.
michael@0:             mIconBitmap = Bitmap.createScaledBitmap(mIconBitmap, doubledSize, doubledSize, true);
michael@0:         } else {
michael@0:             // Otherwise, scale the image to fill the view.
michael@0:             mIconBitmap = Bitmap.createScaledBitmap(mIconBitmap, mActualWidth, mActualWidth, true);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Sets the icon displayed in this Favicon view to the bitmap provided. If the size of the view
michael@0:      * has been set, the display will be updated right away, otherwise the update will be deferred
michael@0:      * until then. The key provided is used to cache the result of the calculation of the dominant
michael@0:      * colour of the provided image - this value is used to draw the coloured background in this view
michael@0:      * if the icon is not large enough to fill it.
michael@0:      *
michael@0:      * @param bitmap favicon image
michael@0:      * @param key string used as a key to cache the dominant color of this image
michael@0:      * @param allowScaling If true, allows the provided bitmap to be scaled by this FaviconView.
michael@0:      *                     Typically, you should prefer using Favicons obtained via the caching system
michael@0:      *                     (Favicons class), so as to exploit caching.
michael@0:      */
michael@0:     private void updateImageInternal(Bitmap bitmap, String key, boolean allowScaling) {
michael@0:         if (bitmap == null) {
michael@0:             showDefaultFavicon();
michael@0:             return;
michael@0:         }
michael@0: 
michael@0:         // Reassigning the same bitmap? Don't bother.
michael@0:         if (mUnscaledBitmap == bitmap) {
michael@0:             return;
michael@0:         }
michael@0:         mUnscaledBitmap = bitmap;
michael@0:         mIconBitmap = bitmap;
michael@0:         mIconKey = key;
michael@0:         mScalingExpected = allowScaling;
michael@0: 
michael@0:         // Possibly update the display.
michael@0:         formatImage();
michael@0:     }
michael@0: 
michael@0:     public void showDefaultFavicon() {
michael@0:         setImageResource(R.drawable.favicon);
michael@0:         mDominantColor = 0;
michael@0:     }
michael@0: 
michael@0:     private void showNoImage() {
michael@0:         setImageDrawable(null);
michael@0:         mDominantColor = 0;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Clear image and background shown by this view.
michael@0:      */
michael@0:     public void clearImage() {
michael@0:         showNoImage();
michael@0:         mUnscaledBitmap = null;
michael@0:         mIconBitmap = null;
michael@0:         mIconKey = null;
michael@0:         mScalingExpected = false;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Update the displayed image and apply the scaling logic.
michael@0:      * The scaling logic will attempt to resize the image to fit correctly inside the view in a way
michael@0:      * that avoids unreasonable levels of loss of quality.
michael@0:      * Scaling is necessary only when the icon being provided is not drawn from the Favicon cache
michael@0:      * introduced in Bug 914296.
michael@0:      *
michael@0:      * Due to Bug 913746, icons bundled for search engines are not available to the cache, so must
michael@0:      * always have the scaling logic applied here. At the time of writing, this is the only case in
michael@0:      * which the scaling logic here is applied.
michael@0:      *
michael@0:      * @param bitmap The bitmap to display in this favicon view.
michael@0:      * @param key The key to use into the dominant colours cache when selecting a background colour.
michael@0:      */
michael@0:     public void updateAndScaleImage(Bitmap bitmap, String key) {
michael@0:         updateImageInternal(bitmap, key, true);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Update the image displayed in the Favicon view without scaling. Images larger than the view
michael@0:      * will be centrally cropped. Images smaller than the view will be placed centrally and the
michael@0:      * extra space filled with the dominant colour of the provided image.
michael@0:      *
michael@0:      * @param bitmap The bitmap to display in this favicon view.
michael@0:      * @param key The key to use into the dominant colours cache when selecting a background colour.
michael@0:      */
michael@0:     public void updateImage(Bitmap bitmap, String key) {
michael@0:         updateImageInternal(bitmap, key, false);
michael@0:     }
michael@0: 
michael@0:     public Bitmap getBitmap() {
michael@0:         return mIconBitmap;
michael@0:     }
michael@0: }