From 396bc20bfdfb996434f5b008234bdfccda8c8f10 Mon Sep 17 00:00:00 2001
From: Christopher Eby <kreed@kreed.org>
Date: Mon, 26 Sep 2011 20:02:32 -0500
Subject: [PATCH] Prevent cover bitmaps for the actives songs from being
 deleted

Since previously we loaded directly from the cache, the actives songs' bitmaps
could be deleted if the next song was changing very frequently. While this is
fairly unlikely to happen, this new intermediate method should be a bit faster
anyway.
---
 src/org/kreed/vanilla/CoverView.java | 42 +++++++++++++++++-----------
 1 file changed, 25 insertions(+), 17 deletions(-)

diff --git a/src/org/kreed/vanilla/CoverView.java b/src/org/kreed/vanilla/CoverView.java
index 65ca73a6..7dc497cd 100644
--- a/src/org/kreed/vanilla/CoverView.java
+++ b/src/org/kreed/vanilla/CoverView.java
@@ -67,6 +67,10 @@ public final class CoverView extends View implements Handler.Callback {
 	 * The current set of songs: 0 = previous, 1 = current, and 2 = next.
 	 */
 	private Song[] mSongs = new Song[3];
+	/**
+	 * The covers for the current songs: 0 = previous, 1 = current, and 2 = next.
+	 */
+	private Bitmap[] mBitmaps = new Bitmap[3];
 	/**
 	 * Cache of cover bitmaps generated for songs. The song ids are the keys.
 	 */
@@ -166,16 +170,11 @@ public final class CoverView extends View implements Handler.Callback {
 		canvas.drawColor(Color.BLACK);
 
 		for (int x = 0, i = 0; i != 3; ++i, x += width) {
-			if (mSongs[i] != null && scrollX + width > x && scrollX < x + width) {
-				long id = mSongs[i].id;
-				if (id == -1)
-					continue;
-				Bitmap bitmap = mBitmapCache.get(id);
-				if (bitmap != null) {
-					int xOffset = (width - bitmap.getWidth()) / 2;
-					int yOffset = (height - bitmap.getHeight()) / 2;
-					canvas.drawBitmap(bitmap, x + xOffset, yOffset, null);
-				}
+			Bitmap bitmap = mBitmaps[i];
+			if (bitmap != null && scrollX + width > x && scrollX < x + width) {
+				int xOffset = (width - bitmap.getWidth()) / 2;
+				int yOffset = (height - bitmap.getHeight()) / 2;
+				canvas.drawBitmap(bitmap, x + xOffset, yOffset, null);
 			}
 		}
 	}
@@ -307,20 +306,25 @@ public final class CoverView extends View implements Handler.Callback {
 	}
 
 	/**
-	 * Generates a bitmap for the given Song and stores it in the cache.
+	 * Generates a bitmap for the given song if the cache does not contain one
+	 * for it, or moves the bitmap to the top of the cache if it does.
 	 *
-	 * Prunes old bitmaps if the timeline becomes full.
+	 * @param i The position of the song in mSongs.
 	 */
-	private void generateBitmap(Song song)
+	private void generateBitmap(int i)
 	{
+		Song song = mSongs[i];
 		if (song == null || song.id == -1)
 			return;
 
 		Bitmap bitmap = mBitmapCache.get(song.id);
 		if (bitmap == null) {
-			mBitmapCache.put(song.id, CoverBitmap.createBitmap(getContext(), mCoverStyle, song, getWidth(), getHeight(), mBitmapCache.discardOldest()));
+			bitmap = CoverBitmap.createBitmap(getContext(), mCoverStyle, song, getWidth(), getHeight(), mBitmapCache.discardOldest());
+			mBitmaps[i] = bitmap;
+			mBitmapCache.put(song.id, bitmap);
 			postInvalidate();
 		} else {
+			mBitmaps[i] = bitmap;
 			mBitmapCache.touch(song.id);
 		}
 	}
@@ -332,8 +336,12 @@ public final class CoverView extends View implements Handler.Callback {
 	public void setSong(int i, Song song)
 	{
 		mSongs[i] = song;
-		if (song != null)
-			mHandler.sendMessage(mHandler.obtainMessage(MSG_GENERATE_BITMAP, song));
+		if (song == null) {
+			mBitmaps[i] = null;
+		} else {
+			mBitmaps[i] = mBitmapCache.get(song.id);
+			mHandler.sendMessage(mHandler.obtainMessage(MSG_GENERATE_BITMAP, i, 0));
+		}
 	}
 
 	/**
@@ -366,7 +374,7 @@ public final class CoverView extends View implements Handler.Callback {
 	{
 		switch (message.what) {
 		case MSG_GENERATE_BITMAP:
-			generateBitmap((Song)message.obj);
+			generateBitmap(message.arg1);
 			break;
 		case MSG_LONG_CLICK:
 			if (Math.abs(mStartX - mLastMotionX) + Math.abs(mStartY - mLastMotionY) < 10) {