Upstream ResourceManager

ui/android/java/src/org/chromium/ui/resources/statics/StaticResource.java

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.ui.resources.statics;
+
+import android.content.res.Resources;
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.graphics.Canvas;
+import android.graphics.Rect;
+import android.graphics.drawable.Drawable;
+
+import org.chromium.ui.resources.Resource;
+
+/**
+ * A representation of a static resource and all related information for drawing it.  In general
+ * this means a {@link Bitmap} and a potential {@link NinePatchData}.
+ */
+public class StaticResource implements Resource {
+    private final Bitmap mBitmap;
+    private final NinePatchData mNinePatchData;
+    private final Rect mBitmapSize;
+
+    /**
+     * Creates a {@link StaticResource} that represents {@code bitmap}.  This will automatically
+     * pull out the {@link NinePatchData} from {@code bitmap} if it exists.
+     * @param bitmap The {@link Bitmap} to build a {@link StaticResource} of.
+     */
+    public StaticResource(Bitmap bitmap) {
+        mBitmap = bitmap;
+        mNinePatchData = NinePatchData.create(mBitmap);
+        mBitmapSize = new Rect(0, 0, mBitmap.getWidth(), mBitmap.getHeight());
+    }
+
+    @Override
+    public Bitmap getBitmap() {
+        return mBitmap;
+    }
+
+    @Override
+    public Rect getBitmapSize() {
+        return mBitmapSize;
+    }
+
+    @Override
+    public Rect getPadding() {
+        return mNinePatchData != null ? mNinePatchData.getPadding() : mBitmapSize;
+    }
+
+    @Override
+    public Rect getAperture() {
+        return mNinePatchData != null ? mNinePatchData.getAperture() : mBitmapSize;
+    }
+
+    /**
+     * Attempts to load the Android resource specified by {@code resId} from {@code resources}.
+     * This will attempt to first load the resource as a {@code Bitmap}.  If that fails it will try
+     * to load the resource as a {@link Drawable}.
+     * @param resources The {@link Resources} instance to load from.
+     * @param resId     The id of the Android resource to load.
+     * @param fitWidth  The smallest width the image can be.  The image will be shrunk to scale to
+     *                  try to get close to this value.  Or use {@code 0} to use the intrinsic
+     *                  size.
+     * @param fitHeight The smallest height the image can be.  The image will be shrunk to scale to
+     *                  try to get close to this value.  Or use {@code 0} to use the intrinsic
+     *                  size.
+     * @return          The loaded {@link StaticResource} or {@code null} if the resource could not
+     *                  be loaded.
+     */
+    public static StaticResource create(Resources resources, int resId, int fitWidth,
+            int fitHeight) {
+        if (resId <= 0) return null;
+        Bitmap bitmap = decodeBitmap(resources, resId, fitWidth, fitHeight);
+        if (bitmap == null) bitmap = decodeDrawable(resources, resId, fitWidth, fitHeight);
+        if (bitmap == null) return null;
+
+        return new StaticResource(bitmap);
+    }
+
+    private static Bitmap decodeBitmap(Resources resources, int resId, int fitWidth,
+            int fitHeight) {
+        BitmapFactory.Options options = createOptions(resources, resId, fitWidth, fitHeight);
+        options.inPreferredConfig = Bitmap.Config.ARGB_8888;
+        Bitmap bitmap = BitmapFactory.decodeResource(resources, resId, options);
+
+        if (bitmap == null) return null;
+        if (bitmap.getConfig() == options.inPreferredConfig) return bitmap;
+
+        Bitmap convertedBitmap = Bitmap.createBitmap(
+                bitmap.getWidth(), bitmap.getHeight(), options.inPreferredConfig);
+        Canvas canvas = new Canvas(convertedBitmap);
+        canvas.drawBitmap(bitmap, 0, 0, null);
+        bitmap.recycle();
+        return convertedBitmap;
+    }
+
+    private static Bitmap decodeDrawable(Resources resources, int resId, int fitWidth,
+            int fitHeight) {
+        try {
+            Drawable drawable = resources.getDrawable(resId);
+            int width = Math.max(drawable.getMinimumWidth(), Math.max(fitWidth, 1));
+            int height = Math.max(drawable.getMinimumHeight(), Math.max(fitHeight, 1));
+            Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
+            Canvas canvas = new Canvas(bitmap);
+            drawable.setBounds(0, 0, width, height);
+            drawable.draw(canvas);
+            return bitmap;
+        } catch (Resources.NotFoundException ex) {
+            return null;
+        }
+    }
+
+    private static BitmapFactory.Options createOptions(Resources resources, int resId,
+            int fitWidth, int fitHeight) {
+        BitmapFactory.Options options = new BitmapFactory.Options();
+        options.inPreferredConfig = Bitmap.Config.ARGB_8888;
+        if (fitWidth == 0 || fitHeight == 0) return options;
+
+        options.inJustDecodeBounds = true;
+        BitmapFactory.decodeResource(resources, resId, options);
+        options.inJustDecodeBounds = false;
+
+        if (options.outHeight <= fitHeight && options.outWidth <= fitWidth) return options;
+
+        int heightRatio = Math.round((float) options.outHeight / (float) fitHeight);
+        int widthRatio = Math.round((float) options.outWidth / (float) fitWidth);
+        options.inSampleSize = Math.min(heightRatio, widthRatio);
+
+        return options;
+    }
+}