Android基于观察者模式下载管理

/** * Copyright 2013 Joan Zapata * * 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.example.mydownloadmanger.adapter.quickadpter; import com.nostra13.universalimageloader.core.ImageLoader; import android.annotation.SuppressLint; import android.content.Context; import android.graphics.Bitmap; import android.graphics.Paint; import android.graphics.Typeface; import android.graphics.drawable.Drawable; import android.os.Build; import android.text.util.Linkify; import android.util.SparseArray; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.view.animation.AlphaAnimation; import android.widget.Adapter; import android.widget.AdapterView; import android.widget.Checkable; import android.widget.ImageView; import android.widget.ProgressBar; import android.widget.RatingBar; import android.widget.TextView; //import com.squareup.picasso.Picasso; //import com.squareup.picasso.RequestCreator; /** * Allows an abstraction of the ViewHolder pattern.<br> * <br> * <p/> * <b>Usage</b> * <p/> * * <pre> * return BaseAdapterHelper.get(context, convertView, parent, R.layout.item) * .setText(R.id.tvName, contact.getName()) * .setText(R.id.tvEmails, contact.getEmails().toString()) * .setText(R.id.tvNumbers, contact.getNumbers().toString()).getView(); * </pre> */ public class BaseAdapterHelper { /** Views indexed with their IDs */ private final SparseArray<View> views; private final Context context; private int position; private View convertView; public int layoutId; /** * Package private field to retain the associated user object and detect a * change */ Object associatedObject; protected BaseAdapterHelper(Context context, ViewGroup parent, int layoutId, int position) { this.context = context; this.position = position; this.layoutId = layoutId; this.views = new SparseArray<View>(); convertView = LayoutInflater.from(context) // .inflate(layoutId, parent, false); convertView.setTag(this); } /** * This method is the only entry point to get a BaseAdapterHelper. * * @param context * The current context. * @param convertView * The convertView arg passed to the getView() method. * @param parent * The parent arg passed to the getView() method. * @return A BaseAdapterHelper instance. */ public static BaseAdapterHelper get(Context context, View convertView, ViewGroup parent, int layoutId) { return get(context, convertView, parent, layoutId, -1); } /** This method is package private and should only be used by QuickAdapter. */ static BaseAdapterHelper get(Context context, View convertView, ViewGroup parent, int layoutId, int position) { if (convertView == null) { return new BaseAdapterHelper(context, parent, layoutId, position); } // Retrieve the existing helper and update its position BaseAdapterHelper existingHelper = (BaseAdapterHelper) convertView .getTag(); if (existingHelper.layoutId != layoutId) { return new BaseAdapterHelper(context, parent, layoutId, position); } existingHelper.position = position; return existingHelper; } /** * This method allows you to retrieve a view and perform custom operations * on it, not covered by the BaseAdapterHelper.<br/> * If you think it's a common use case, please consider creating a new issue * at https://github.com/JoanZapata/base-adapter-helper/issues. * * @param viewId * The id of the view you want to retrieve. */ public <T extends View> T getView(int viewId) { return retrieveView(viewId); } @SuppressWarnings("unchecked") protected <T extends View> T retrieveView(int viewId) { View view = views.get(viewId); if (view == null) { view = convertView.findViewById(viewId); views.put(viewId, view); } return (T) view; } /** * Will set the text of a TextView. * * @param viewId * The view id. * @param value * The text to put in the text view. * @return The BaseAdapterHelper for chaining. */ public BaseAdapterHelper setText(int viewId, String value) { TextView view = retrieveView(viewId); view.setText(value); return this; } public BaseAdapterHelper setText(int viewId, int value) { TextView view = retrieveView(viewId); view.setText(value); return this; } /** * Will set the image of an ImageView from a resource id. * * @param viewId * The view id. * @param imageResId * The image resource id. * @return The BaseAdapterHelper for chaining. */ public BaseAdapterHelper setImageResource(int viewId, int imageResId) { ImageView view = retrieveView(viewId); view.setImageResource(imageResId); return this; } /** * Will set background color of a view. * * @param viewId * The view id. * @param color * A color, not a resource id. * @return The BaseAdapterHelper for chaining. */ public BaseAdapterHelper setBackgroundColor(int viewId, int color) { View view = retrieveView(viewId); view.setBackgroundColor(color); return this; } /** * Will set background of a view. * * @param viewId * The view id. * @param backgroundRes * A resource to use as a background. * @return The BaseAdapterHelper for chaining. */ public BaseAdapterHelper setBackgroundRes(int viewId, int backgroundRes) { View view = retrieveView(viewId); view.setBackgroundResource(backgroundRes); return this; } /** * Will set text color of a TextView. * * @param viewId * The view id. * @param textColor * The text color (not a resource id). * @return The BaseAdapterHelper for chaining. */ public BaseAdapterHelper setTextColor(int viewId, int textColor) { TextView view = retrieveView(viewId); view.setTextColor(textColor); return this; } /** * Will set text color of a TextView. * * @param viewId * The view id. * @param textColorRes * The text color resource id. * @return The BaseAdapterHelper for chaining. */ public BaseAdapterHelper setTextColorRes(int viewId, int textColorRes) { TextView view = retrieveView(viewId); view.setTextColor(context.getResources().getColor(textColorRes)); return this; } /** * Will set the image of an ImageView from a drawable. * * @param viewId * The view id. * @param drawable * The image drawable. * @return The BaseAdapterHelper for chaining. */ public BaseAdapterHelper setImageDrawable(int viewId, Drawable drawable) { ImageView view = retrieveView(viewId); view.setImageDrawable(drawable); return this; } /** * Will download an image from a URL and put it in an ImageView.<br/> * It uses Square's Picasso library to download the image asynchronously and * put the result into the ImageView.<br/> * Picasso manages recycling of views in a ListView.<br/> * If you need more control over the Picasso settings, use * {BaseAdapterHelper#setImageBuilder}. * * @param viewId * The view id. * @param imageUrl * The image URL. * @ret