udacity android 实践笔记: lesson 4 part b

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udacity android 实践笔记: lesson 4 part b

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作者：干货店打杂的 /titer1 /Archimedes
出处：https://code.csdn.net/titer1
联系：1307316一九六八(短信最佳)
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tips:https://code.csdn.net/titer1/pat_aha/blob/master/Markdown/android/

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摘要

• 完全展示content provider添加的过程
• 动态展示android单元测试的过程
  动图出没喔！o(^▽^)o，动图在最后

overviw 图

还是老图，(create / insert /query)

下面 我们开始 content provider的学习

复习四大 组件content provider
service
broadcast provider
actvity 

本章 overview

4.07 init code for content provider

- 测试打桩函数就占了大半
- 然后传统的函数里面修改了 weatherContrace
- 增加了 weatherProvider
- 修改了 fetchweatherTask函数，代码的来源是
从 forececastFragment代码拆解出来的。
- 除了修改weatherContrace,其他文件都是 新增加的

关键词 uri

weatherContract里面增加的最多就是生成uri的函数

/* Inner class that defines the table contents of the location table */public static final class LocationEntry implements BaseColumns {...public static Uri buildLocationUri(long id) {return ContentUris.withAppendedId(CONTENT_URI, id);}}===

    /* Inner class that defines the table contents of the weather table */public static final class WeatherEntry implements BaseColumns {...public static Uri buildWeatherLocation(String locationSetting) {return null;}public static Uri buildWeatherLocationWithStartDate(String locationSetting, long startDate) {long normalizedDate = normalizeDate(startDate);return CONTENT_URI.buildUpon().appendPath(locationSetting).appendQueryParameter(COLUMN_DATE, Long.toString(normalizedDate)).build();}public static Uri buildWeatherLocationWithDate(String locationSetting, long date) {return CONTENT_URI.buildUpon().appendPath(locationSetting).appendPath(Long.toString(normalizeDate(date))).build();}public static String getLocationSettingFromUri(Uri uri) {return uri.getPathSegments().get(1);}public static long getDateFromUri(Uri uri) {return Long.parseLong(uri.getPathSegments().get(2));}public static long getStartDateFromUri(Uri uri) {String dateString = uri.getQueryParameter(COLUMN_DATE);if (null != dateString && dateString.length() > 0)return Long.parseLong(dateString);elsereturn 0;}}
}

4.08 uri location with weather

仅2处更新

1/2 weatherContract

        /*Student: This is the buildWeatherLocation function you filled in.*/public static Uri buildWeatherLocation(String locationSetting) {return CONTENT_URI.buildUpon().appendPath(locationSetting).build();//上一版本这里返回空值}

##2/2 test

仅仅打开 这里的注释
“` java
/*
Students: This is NOT a complete test for the WeatherContract — just for the functions
that we expect you to write.
*/
public class TestWeatherContract extends AndroidTestCase {

// intentionally includes a slash to make sure Uri is getting quoted correctly
private static final String TEST_WEATHER_LOCATION = "/North Pole";
private static final long TEST_WEATHER_DATE = 1419033600L;  // December 20th, 2014/*Students: Uncomment this out to test your weather location function.*/
public void testBuildWeatherLocation() {Uri locationUri = WeatherContract.WeatherEntry.buildWeatherLocation(TEST_WEATHER_LOCATION);assertNotNull("Error: Null Uri returned.  You must fill-in buildWeatherLocation in " +"WeatherContract.",locationUri);assertEquals("Error: Weather location not properly appended to the end of the Uri",TEST_WEATHER_LOCATION, locationUri.getLastPathSegment());assertEquals("Error: Weather location Uri doesn't match our expected result",locationUri.toString(),"content://com.example.android.sunshine.app/weather/%2FNorth%20Pole");
}

}
“`

4.09 write uri matcher

1/2 weatherProvider

这是框架里面的代码，更新一处

    /*Students: Here is where you need to create the UriMatcher. This UriMatcher willmatch each URI to the WEATHER, WEATHER_WITH_LOCATION, WEATHER_WITH_LOCATION_AND_DATE,and LOCATION integer constants defined above.  You can test this by uncommenting thetestUriMatcher test within TestUriMatcher.*/static UriMatcher buildUriMatcher() {// I know what you're thinking.  Why create a UriMatcher when you can use regular// expressions instead?  Because you're not crazy, that's why.// All paths added to the UriMatcher have a corresponding code to return when a match is// found.  The code passed into the constructor represents the code to return for the root// URI.  It's common to use NO_MATCH as the code for this case.final UriMatcher matcher = new UriMatcher(UriMatcher.NO_MATCH);final String authority = WeatherContract.CONTENT_AUTHORITY;// For each type of URI you want to add, create a corresponding code.matcher.addURI(authority, WeatherContract.PATH_WEATHER, WEATHER);matcher.addURI(authority, WeatherContract.PATH_WEATHER + "/*", WEATHER_WITH_LOCATION);matcher.addURI(authority, WeatherContract.PATH_WEATHER + "/*/#", WEATHER_WITH_LOCATION_AND_DATE);matcher.addURI(authority, WeatherContract.PATH_LOCATION, LOCATION);return matcher;}

2/2 test

依然是已经写好的测试代码框架，这里仅仅打开注释

public class TestUriMatcher extends AndroidTestCase {
.../*Students: This function tests that your UriMatcher returns the correct integer valuefor each of the Uri types that our ContentProvider can handle.  Uncomment this when you areready to test your UriMatcher.*/public void testUriMatcher() {UriMatcher testMatcher = WeatherProvider.buildUriMatcher();assertEquals("Error: The WEATHER URI was matched incorrectly.",testMatcher.match(TEST_WEATHER_DIR), WeatherProvider.WEATHER);assertEquals("Error: The WEATHER WITH LOCATION URI was matched incorrectly.",testMatcher.match(TEST_WEATHER_WITH_LOCATION_DIR), WeatherProvider.WEATHER_WITH_LOCATION);assertEquals("Error: The WEATHER WITH LOCATION AND DATE URI was matched incorrectly.",testMatcher.match(TEST_WEATHER_WITH_LOCATION_AND_DATE_DIR), WeatherProvider.WEATHER_WITH_LOCATION_AND_DATE);assertEquals("Error: The LOCATION URI was matched incorrectly.",testMatcher.match(TEST_LOCATION_DIR), WeatherProvider.LOCATION);}

···

4.10 register content provider

1/2

这里仅仅使能（打开注释） testProviderRegistry

public class TestProvider extends AndroidTestCase {.../*This test checks to make sure that the content provider is registered correctly.Students: Uncomment this test to make sure you've correctly registered the WeatherProvider.*/public void testProviderRegistry() {PackageManager pm = mContext.getPackageManager();// We define the component name based on the package name from the context and the// WeatherProvider class.ComponentName componentName = new ComponentName(mContext.getPackageName(),WeatherProvider.class.getName());try {// Fetch the provider info using the component name from the PackageManager// This throws an exception if the provider isn't registered.ProviderInfo providerInfo = pm.getProviderInfo(componentName, 0);// Make sure that the registered authority matches the authority from the Contract.assertEquals("Error: WeatherProvider registered with authority: " + providerInfo.authority +" instead of authority: " + WeatherContract.CONTENT_AUTHORITY,providerInfo.authority, WeatherContract.CONTENT_AUTHORITY);} catch (PackageManager.NameNotFoundException e) {// I guess the provider isn't registered correctly.assertTrue("Error: WeatherProvider not registered at " + mContext.getPackageName(),false);}}}

androidManifest update

        <provider
            android:authorities="com.example.android.sunshine.app"android:name=".data.WeatherProvider" />

小憩

增加provider布凑
- 估计要从 1代版本代码 和 2代代码 进行比较

聪明的编译器

智能提示
android 在debug模式下，有很有趣的话题在里面，比如变量值的提示
还有搜索字符时，主动过滤注释里面字符

test ok 单元测试的方法 && testPractise

并且 我没有选右键触发，而是直接 run ( shift f10)
（4a-28 ）里面单元测试的方法，完全可以复现

- 展现运行的配置
- 展示出错情形如何定位错误
- 展示正常情况

使用的是 sunshine version2 的4.02的代码，code: testPractise

todo 实践后思考
空白的android test工程是怎样的？
4.02章节里面，命名只有有效的3个testcase,怎么显示有6个testcase ?

testDb之testCreateDb

4.04 (git version) delete the testPractise,

实际运行记录：
我在所有的 assertTrue,assertFalse,assertEqual
位置都下了断点，但是只有testDb中的testCreateDb 被触发，
数字上，run窗口显示的“6 of 6”ok,
但6个中的4个被触发，
我怀疑这个6是不是显示过时

testdb之testLocationTable

测试完全通过.

• 该函数完整的调用了db的操作函数
  
  • insert
  • query

并且有趣的是调用了TestUtilities.validateCurrentRecord。
(这里面还有2个assert,这里面的断言终于被触发了)

这是我观察中
testUtilities类中函数的第一次调用，
上一轮，我在这个类的static函数里面设置断点，
都没有被调用。

还有这个类testUtilities提供了数据库插入的样本数据

todo
实践后思考：
既然单元测试都是利用AndroidTestCase
那么为什么每次都是testDb被调用，
而其他AndroidTestCase的继承类testUtilities 没有被直接调用.

testWeatherTable 和重构 testLocationTable

4.06 lesson,
而且有趣的是前者内部调用调用了
locationTable的内容

竟然所有的测试通过了

todo 内容深入分析// Fifth Step: Validate the location QueryTestUtilities.validateCurrentRecord("testInsertReadDb weatherEntry failed to validate",weatherCursor, weatherValues);

小憩

github 前6个小节，就是认识单元测试

单元测试的魔力很大啊，这里

后续

from 4.06 -4.10 (github)
测试函数有：
- test weatherContract
- test uri matcher
- test Provider
- test providerRegistery

构造一个content provider，每个模块都不能马虎

晚安 小憩

至少方向是光明的

下一天 复习

解释 前面 为什么 不是 全部的uri都被命中

再看 weather provider 和 testProvider的演示
作者是逐一功能的enable,逐一测试。逐渐深入

几乎每种testProvider的函数(query/getType/insert/updat)
都含有uri matcher的筛选

新近发现 可以 查看 每一个测试的内容：

video 4b-24 是个阶段总结

bulkinsert 其实利用了事务，只有endtrancsation 才执行操作

小节

小节：整章节 就是 uri 使用
- define uri
- update uri(feflect to number)
- uri matcher (I think ,here addmatch)
- implement (I think, sUriMatcher.match(uri);)

说到，开源很多 封装了 content provider ? toco
如何理解 notification oserver ..here

整合

至此，我们的content provider 还没有和 database 联合起来。
操作不是 test*.java,也不主要是 weatherprovider里面

我们将精力集中到 FetchweatherTask
- addlocation
- getWeatherDataFromJson insert + query part
(网络收报后的处理例程)

看到凡是使用了getContentResolver的地方，都是利用了contentprovider的地方，

最后

为了ui theread 更加流畅，引出Loader
至此，我们的video 来到4b的借书，代码
代码范围是：

todo 附code

小节

android 你好
android 再见
呵呵，本博客android暂停更新，如果有兴趣可以短信联系

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