Improve GallerySpider

app/src/main/java/com/hippo/ehviewer/gallery/GalleryProvider.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2015 Hippo Seven
+ *
+ * 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.hippo.ehviewer.gallery;
+
+public interface GalleryProvider {
+
+    /**
+     * There is no worker to get the page now.
+     * There is no guarantee that the {@link GalleryProviderListener} will be
+     * called, so do some reactions after get it.
+     */
+    Object RESULT_NONE = new Object();
+
+    /**
+     * Worker failed to get the page
+     * There is no guarantee that the {@link GalleryProviderListener} will be
+     * called, so do some reactions after get it.
+     */
+    Object RESULT_FAILED = new Object();
+
+    /**
+     * {@link GalleryProviderListener} will be calls soon.
+     */
+    Object RESULT_WAIT = new Object();
+
+    /**
+     * Request is out of range
+     */
+    Object RESULT_OUT_OF_RANGE = new Object();
+
+    /**
+     * Request special index page
+     *
+     * @param index the index to request
+     * @return Might be on of {@link #RESULT_NONE}, {@link #RESULT_FAILED},
+     * {@link #RESULT_WAIT}, {@link #RESULT_OUT_OF_RANGE}. It could be
+     * {@link Float} it means the percent of getting the page
+     */
+    Object request(int index);
+
+    /**
+     * Just like {@link #request(int)}, but it ignores cache or local file
+     *
+     * @param index the index to request
+     * @return just like {@link #request(int)}
+     */
+    Object forceRequest(int index);
+
+    /**
+     * Gallery provider may fails, so we need
+     */
+    void restart();
+
+    void retry();
+
+    void addGalleryProviderListener(GalleryProviderListener listener);
+
+    void removeGalleryProviderListener(GalleryProviderListener listener);
+}