| /* |
| * Copyright (C) 2013 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.mail.ui; |
| |
| import android.graphics.Bitmap; |
| |
| /** |
| * A canvas to draw loaded photos. |
| */ |
| public interface ImageCanvas { |
| |
| /** |
| * Dimensions holds the desired width, height, and scale for a bitmap being |
| * placed in the ImageCanvas. |
| */ |
| public static class Dimensions { |
| public int width; |
| public int height; |
| public float scale; |
| |
| public static final float SCALE_ONE = 1.0f; |
| public static final float SCALE_HALF = 0.5f; |
| public static final float SCALE_QUARTER = 0.25f; |
| |
| public Dimensions() { |
| } |
| |
| public Dimensions(int w, int h, float s) { |
| width = w; |
| height = h; |
| scale = s; |
| } |
| |
| @Override |
| public String toString() { |
| return String.format("Dimens [%d x %d]", width, height); |
| } |
| } |
| |
| /** |
| * Draw/composite the given Bitmap corresponding with the key 'id'. It will be sized according |
| * to whatever {@link #getDesiredDimensions(Object, Dimensions)} reported when the |
| * decode request was made. |
| * |
| * @param decoded an exactly-sized, decoded bitmap to display |
| * @param key |
| */ |
| void drawImage(Bitmap decoded, Object key); |
| |
| /** |
| * Reset all state associated with this view so that it can be reused. |
| */ |
| void reset(); |
| |
| /** |
| * Outputs the desired dimensions that the object with key 'id' would like to be drawn to. |
| * |
| * @param key |
| * @param outDim caller-allocated {@link Dimensions} object to house the result |
| */ |
| void getDesiredDimensions(Object key, Dimensions outDim); |
| |
| /** |
| * Return an arbitrary integer to associate with any asynchronous requests for images that |
| * currently belong to this canvas. If, later on when results are available, the generation |
| * that is then reported does not match, the photo manager will assume the image is no longer |
| * desired and will not offer the image. |
| * <p> |
| * Implementors should basically treat this as a counter to increment upon reset() or |
| * data binding. |
| */ |
| int getGeneration(); |
| } |