Android journey 1@关于编码风格和命名规范

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/*
* 1.关于编程风格：每一位程序猿可能都有自己独特的编程风格，但是有些规则是大家都必须遵守的，特别
*   是在工作的过程中，良好的代码风格能大大提高代码本身的可阅读性和维护性，也更有利于别人修改你
*   的代码。风格问题涉及到的都是细节相关的问题，读者朋友们或许都听过“细节决定成败”这句话，这句话
*   在这里同样生效，不过是换了种意思，就是“细节体现你的专业程度”，所以作为一名程序猿，我们应该从
*   编写代码的训练中养成良好的编码习惯，如命名规范，排版规范，写好注释等。下面具体说明下：
*/
/*
* 1）整个Project相关内容的目录规范：（通常可以包含以下几个文件夹）
*    #.Requirement Doc: project的需求文档说明
*    #.Design：有关设计方面的说明
*    #.Planning&Log：计划、日志、会议等
*    #.Test：测试及其报告
*    #.Study:学习资料及demo
*    #.Deployment:发布，部署
*    #.src: 源代码
*    #.help：帮助文档
*    #. ...（根据自己需求添加合适文档）
*    注意事项：在IDE建立project的时候，包即目录（java），包名全小写，且一般不超过3层，命名为：【公司】.【项目】.【模块】
*/
/*
* 2）命名规范：
*    #、Pascal命名法：每个单词首字母大写，其余小写，如“ActivityDemo”，主要应用于：文件名，普通类名，构造函数等
*    #、Camel命名法：第一个单词全小写，其余单词按pascal命名，如“myName”,主要应用于：方法名（动宾短语），普通函数名等
*    #、匈牙利命名法（使用前缀，后缀命名）：如对于整型变量，可以“int intMyAge;”
*    #、下划线命名法：主要在常量（全大写）中使用，分隔两个不同单词
*    其他常见命名：私有成员变量：“mMyName”;静态变量：“sMyName”;方法参数：“pMyName”；
*    当然命名规则的使用主要看已有项目的要求，若新启动一个项目，编码前团队必须先统一命名规范
*/
/*
* 3)其他需要注意的地方：
*   1、一个方法不超过35行代码
*   2、不要去修改机器自动生成的代码
*   3、final String取代String，即不要直接写字符串
*   4、循环语句中不用return
*   5、属性用set(),get()方法操控
*   6、不要再系统生成函数中写复杂代码，复杂代码通常用函数调用解决
*   7、虽然class能搞定一切，但使用接口暴露信息会更好
*   8、switch语句中无论如何都要有default
*   9、同类的import包放在一起
*   ...<br>*
*/
//下面看一下Android源码中的代码：
 
/*
 * Copyright (C) 2006 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 android.app;
 
import com.android.internal.app.ActionBarImpl;
import com.android.internal.policy.PolicyManager;
 
import android.os.Build;
import android.os.Bundle;
import android.os.UserHandle;
import android.text.Selection;
import android.text.SpannableStringBuilder;
import android.text.TextUtils;
import android.text.method.TextKeyListener;
import android.util.AttributeSet;
import android.util.EventLog;
 
/**可在注释中嵌入HTML标签，在生成javadoc的时候控制各种属性等
 * An activity is a single, focused thing that the user can do.  Almost all
 * activities interact with the user, so the Activity class takes care of
 * creating a window for you in which you can place your UI with
 * {@link #setContentView}.  While activities are often presented to the user
 * as full-screen windows, they can also be used in other ways: as floating
 * windows (via a theme with {@link android.R.attr#windowIsFloating} set)
 * or embedded inside of another activity (using {@link ActivityGroup}).
 *
 * There are two methods almost all subclasses of Activity will implement:
 * 
 * <ul>
 *     <li> {@link #onCreate} is where you initialize your activity.  Most
 *     importantly, here you will usually call {@link #setContentView(int)}
 *     with a layout resource defining your UI, and using {@link #findViewById}
 *     to retrieve the widgets in that UI that you need to interact with
 *     programmatically.
 * 
 *     <li> {@link #onPause} is where you deal with the user leaving your
 *     activity.  Most importantly, any changes made by the user should at this
 *     point be committed (usually to the
 *     {@link android.content.ContentProvider} holding the data).
 * </ul>
 ...
 */
public class Activity extends ContextThemeWrapper
        implements LayoutInflater.Factory2,
        Window.Callback, KeyEvent.Callback,
        OnCreateContextMenuListener, ComponentCallbacks2 {
    private static final String TAG = "Activity";
    private static final boolean DEBUG_LIFECYCLE = false;
 
    /** Standard activity result: operation canceled. */
    //常量命名
    public static final int RESULT_CANCELED    = 0;
    /** Standard activity result: operation succeeded. */
    public static final int RESULT_OK           = -1;
    /** Start of user-defined activity results. */
    public static final int RESULT_FIRST_USER   = 1;
 
    static final String FRAGMENTS_TAG = "android:fragments";
 
    private static final String WINDOW_HIERARCHY_TAG = "android:viewHierarchyState";
    private static final String SAVED_DIALOG_IDS_KEY = "android:savedDialogIds";
    private static final String SAVED_DIALOGS_TAG = "android:savedDialogs";
    private static final String SAVED_DIALOG_KEY_PREFIX = "android:dialog_";
    private static final String SAVED_DIALOG_ARGS_KEY_PREFIX = "android:dialog_args_";
 
    private static class ManagedDialog {
        Dialog mDialog;
        Bundle mArgs;
    }
    private SparseArray<ManagedDialog> mManagedDialogs;
 
    // set by the thread after the constructor and before onCreate(Bundle savedInstanceState) is called.
    //私有变量命名
    private Instrumentation mInstrumentation;
    private IBinder mToken;
    private int mIdent;
 
    static final class NonConfigurationInstances {
        Object activity;
        HashMap<String, Object> children;
        ArrayList<Fragment> fragments;
        HashMap<String, LoaderManagerImpl> loaders;
    }
    /* package */ NonConfigurationInstances mLastNonConfigurationInstances;
     
    private Window mWindow;
 
    /** 
     * Change the intent returned by {@link #getIntent}.  This holds a 
     * reference to the given intent; it does not copy it.  Often used in 
     * conjunction with {@link #onNewIntent}. 
     *  
     * @param newIntent The new Intent object to return from getIntent 
     * 
     * @see #getIntent
     * @see #onNewIntent
     *自定义javadoc标签
     *@author ..
     *@date  ..
     *@modify  ..(who,when..)
     */
    public void setIntent(Intent newIntent) {
        mIntent = newIntent;
    }