如何调试HelloAndrid-日志-光明领域，提供各类软件下载，各类日志

日志分类

文章日志

如何调试HelloAndrid

日志类别：技术

2013-08-28 22:43

    在Eclipse开发工具中调试程序的方法很多，使用Eclipse调试Android程序时需要注意·些细节上的问题。许多刚接触Android的开发者，在调试Android程序时总是不能迅速地找到程序的错误所在，Eclipse+ADT的开发环境中没有直接跟踪对象内容的方法，但是我们可以使用Google提供的ADT插件DDMS(Dalvik Debug Monitor Serrvice)在Eclipse上轻松地调试Android程序。DDMS为我们提供了很多功能，例如:测试设备截屏，针对特定的进程查看正在运行的线程以及堆信息，LogCat，广播状态信息，模拟电话呼叫，接收SMsa虚拟地理坐标等等，下面我们通过DDMS来调试我们的Hello Androidl项目口
    (1)将Eclipse开发工具的工作界面切换到DDMS标签。首先确定Eclipse开发工具右上角是否有DDMS标签，如果有，则直接点击该标签即可切换到DDMS工作界面，如果没有，则点击“Open Perspective按钮，选择 'Other...”命令按钮，打开“Open Perspective”对话框。在"Open Perspective”对话框中选择"DDMS”选项，然后点击`ok”按钮。
    (2)在DDMS”界面中选择“Devices”标签，查看其菜单的功能，可以看到Debug Process(调试进程)、UPdate Threads(更新线程)、Update HeaP(更新堆)、Cause GC(引起垃圾回收)、Stop Process(停止进程)、Screen Capture"(屏幕截图)、Rest adb(重启Android Debug Bridge)菜单选项。
    从中可以观察到Android程序运行时的各种状态，比如进程信息、线程分析、堆内存的占用，结束一个进程等。当然，这些操作都是在DDMs框架’下进行的，日常开发的程序是羌法执行调用的。如果adb调试桥运行不稳定，可以选择“Reset adb”来重新启动adb.exe”进程。’下面我们介绍如何使用DDMS的“Logcat”来调试Android程序，步骤如下:
    (l)“Logcat”通过“android.util.Log类的静态方法来查找错误和打印系统口志消息。它是一个进行日志输出的API，我们在Android程序中可以随时为某一个对象插入一个Log，然后在DDMS中观察Logcat的输出是否正常。android.util.Log常用的方法有以下5个:
    口Log.v(String tag,String msg);
    口Log.d(String tag,String msg);
    口Log.i(String tag,String msg);
    口Log.w(Striyng t, String msg);
    口Log.e(String tag,String msg);
　　这5种方法的首字母分别对应VERBOSE, DEBUG, INFO, WARN, ERROR当利用DDMS进行调试时，它们的区别并不大，只是显示的颜色不同，可以控制要显示的某一类错误，一般如果使用“断点”方式来调试程序，则使用Log.e比较合适·但是根据规范建议Log.v,Log.d信息应当只存在于开发过程中，最终版本只可以包含Log.i, Log.w, Log.e这三种日志信息。下面我们对"HelloAndroid"程序进行调试，首先修改“HelloAndroid.java”。
　　(2)点击“RUN”→“Debug”菜单命令，进入调试模式。
　　(3)切换到“DDMS”界面，点击“LogCat标签，即可查看我们刚刚在程序中打印的Log信息。用不同颜色表示了不同等级的信息，这样就可方便地对程序进行跟踪，使得调试Android程序更加方便。
　　在调试.Android程序时，同样可以通过设置断点的方式来调试程序。在启动应用程序进行调试时，Eclipse会自动切换到Debug透视图。毫无疑问，最常见的调试步骤是设置断点，这样可以检查条件语句或循环内的变量和值。要在java透视图的Package Explorer透视图中设置断点，双击选择的源代码文件，在一个编辑器中打开它。遍历代码，将鼠标放在可疑代码一行的标记栏(在编辑器区域的左侧)上，双击即可设置断点。
　　一旦找到错误发生的位置，你可能想知道在程序崩溃之前它在做什么。一种方法是单步执行程序的每行语句，直到运行到可疑的那一行。有时候最好只运行‘段代码，在可疑处停止运行，检查数据。另一种方法是声明条件断点，断点在表达式值发生变化时触发。我门设置条件“savedInstanceState=null”，当满足这个条什时，程序就会挂起。除此之外，在输入条件表达式时，也可以使用代码帮助。为了在Debug透视图的编辑器中计算表达式的值，选择设置了断点的那行代码，在上下文菜单中.通过try+shift+I或右键单击你感兴趣的变量并选择Inspect选项。在当前堆栈框架的上下文中会计算表达式的值，在Display窗口的Expressions视图中会显示结果。
　要在Debug视图中挂起执行线程，选择一个运行线程，单击Debug视图上具栏中的Suspend。该线程的当前调用堆栈就会显示出来，当前执行的代码行就会在Debug透视图中的编辑器中高亮显示。挂起一个线程时，将鼠标放在java编辑器中的变量上，该变量的值就会在一个小的悬停窗口中显示出来。此时，该线程的项部堆栈框架也会自动选中，其中的可视变量也会在Variables视图中显示出来，可以通过单击Variables视图中合适的变量名来检查变量。
   以上列举了一些在Eclipse编辑器中常用的调试方式，当然调试的方式很多，读者同样可以根据自己的需要选择不同的方式进行调试。希望读者能够根据不同的错误采取不同的方式进行调试，使错误能快速地出现在眼前。

本文转自【上海青大实训】,原文地址：http://www.shaccp.net/base/android/246.html

0 0

Markus：

We need someone with experience <a href=" http://accutane.click/#beset ">order accutane</a> University of Utah physicists invented a new "spintronic" organic light-emitting diode or OLED that promises to be brighter, cheaper and more environmentally friendly than the kinds of LEDs now used in television ...

2016-03-22 16:34 支持(0) 反对(0)

George：

I'd like to speak to someone about a mortgage <a href=" http://levitra.uno/ ">cheap levitra</a> Yum! Brands Inc fell 8.4 percent to $65.30 as boththe worst performer and biggest drag on the S&P 500 after theKFC parent warned it will take longer than expected forrestaurant sales to rebound in China, which accounts for morethan half the company's overall operating profit.

2016-03-22 09:20 支持(0) 反对(0)

Monty：

Withdraw cash <a href=" http://propecia.pro/#earnest ">order propecia</a> Isaacson's label handles her music. "It was her dream to have a string orchestra interpret her work," he said of the nun, who sat front and center at the concerts. "She was not recognized in Ethiopia; when she became religious her music is not quite church music. We're hoping this festival may change this. Itâs a very extraordinary moment for her." â¨â¨

2016-03-22 06:08 支持(0) 反对(0)

Stanton：

Would you like to leave a message? <a href=" http://virility.definition.webster.staminahealth.com/virility-definition-webster.html#elect ">cheap virility</a>  "From Edward Snowden to Aaron Alexis, what's emerging is a pattern of failure on the part of this company, and a failure of this entire system, that risks nothing less than our national security and the lives of Americans," Senator Claire McCaskill said in a statement Thursday.
<a href=" http://vigorax.medicine.staminahealth.com/vigorax-medicine.html ">what is vigorax pure power</a>  It said warming had slowed "in roughly equal measure" because of random variations in the climate and the impact of factors such as volcanic eruptions, when ash dims sunshine, and a cyclical decline in the sun's output.
<a href=" http://price.of.virility.ex.in.india.staminahealth.com/price-of-virility-ex-in-india.html ">price of virility ex in india</a>  Air Force leaders called the move a step in the right direction but warned that budget cuts hav

2016-03-11 03:13 支持(0) 反对(0)

Kareem：

very best job <a href=" http://test.x.180.60.staminahealth.com/test-x-180-60.html ">where to buy test x180</a>  The government has gradually been selling off the rest of the stock, with the goal of exiting the investment by April of next year. As of June 6, it still owned 189 million shares, or about 14 percent of the company, according to the report.
<a href=" http://febrex.plus.pregnancy.staminahealth.com/febrex-plus-pregnancy.html ">febrex plus pregnancy</a>  Investors were mainly encouraged by its positive netinterest margins, Credit Suisse analysts said in a note. This ismainly due to its higher asset yield, strong fee income and areduction in its inter-bank assets, they added.
<a href=" http://rexavar.activator.staminahealth.com/rexavar-activator.html#eldest ">rexavar pills price</a>  The Copiapo Court of Appeals on Monday ordered a freeze on construction of the project, which straddles the Chile-Argentine border high in the Andes, until the company builds infrastructure to pre

2016-03-11 03:13 支持(0) 反对(0)

Warner：

Special Delivery <a href=" http://xanogen.before.and.after.pics.staminahealth.com/xanogen-before-and-after-pics.html#peanut ">coupon code for xanogen</a>  The lack of a coherent plan to help the nation's rapidly growing pool of seniors afford long-term care was a major reason why Congress approved a new long-term care insurance program in 2010 as part of the health care reform law.
<a href=" http://maxoderm.gel.staminahealth.com/maxoderm-gel.html#polish ">maxoderm gel</a>  "People need to love and be loved (sexually and non-sexually) by others. In the absence of these elements, many people become susceptible to loneliness, social anxiety, and depression that could affect their working life," said study author Nick Drydakis, an economics lecturer at Angila Ruskin University in Cambridge, England in an email, via CBS News.
<a href=" http://neosize.xl.purchase.staminahealth.com/neosize-xl-purchase.html ">neosize xl price in rupees</a>  A severe flu strain swept the country last winter,

2016-03-11 03:13 支持(0) 反对(0)

Jack：

I came here to work <a href=" http://staminahealth.com/maps/sitemap3.html ">filagra wirkung</a> Wheatley's "Kill List" kicks off with a suburban dinner party and ends in scenes of excruciating, occult horror. His "A Field in England", released earlier this year, mixes magic mushrooms with England's 17th-century civil war.

2016-03-09 03:20 支持(0) 反对(0)

Frederic：

I'll put him on <a href=" http://rxonlineprescription.com/maps/sitemap11.html#leisure ">costco temecula pharmacy phone</a> Tulsa police spokesman Capt. Steve Odom said a gun was recovered but that it will have to be tested to see if it is linked to the Saturday night shooting. Odom said the alleged shooters and the victims were all Hmong and that there was "probably a relationship" between the men charged and the victims.

2016-03-09 03:20 支持(0) 反对(0)

Wilbur：

I've just started at <a href=" http://staminaenhanced.com/maps/sitemap5.html#develop ">libido foods</a> Officials initially decided not to remove the arrow, since the bird was able to fly without difficulty. The DNR again came across the goose at the end of June when biologists were banding geese and decided to take action

2016-03-09 03:20 支持(0) 反对(0)

Dogkill：

Could you ask him to call me? <a href=" http://staminahealth.com/maps/sitemap6.html#lame ">omega 3 prostaglandin</a> According to the survey, the barriers most commonly cited by shoppers against eating more healthfully include cost, motivation, difficulty in changing habits, too much conflicting information, taste and time. Looking to these so-called healthier processed foods, many of these barriers make a great deal of sense. "Healthier" versions of processed foods almost invariably cost more, don't taste as good and are often confusingly contradictory in their messaging (Does the presence of "whole grains" really make Froot Loops a healthful choice?).

2016-03-09 03:01 支持(0) 反对(0)

Salvador：

We need someone with experience <a href=" http://mainsildenafil.com/maps/sitemap1.html ">venta de viagra cubano</a> As its labour costs rose faster than in neighbouring Germanyover the last decade, France's share of international exportmarkets has declined, costing hundreds of thousands of jobs inthe industrial sector.

2016-03-09 03:01 支持(0) 反对(0)

Ellis：

Did you go to university? <a href=" http://staminaprotect.com/maps/sitemap6.html ">is zenegra good</a> The bank reported declines in revenue, lending margins andthe backlog of new mortgage loans. The efficiency ratio, whichmeasures costs as a percentage of revenue, rose to 59.1 percent,missing the firmâs target of 55 percent to 59 percent.Noninterest expenses were little changed at $12.1 billion.

2016-03-09 03:01 支持(0) 反对(0)

Carmine：

I can't get a dialling tone <a href=" http://mainsildenafil.com/maps/sitemap4.html ">levitra resmi satä±å sitesi</a> After making off with his preferred loot of electric cables, Mr Lang used the profits to bankroll an expensive penchant for state-of-the-art mobile phones including handsets made by Samsung, Sony and Apple. He reportedly used the smart phones to swat up on the latest techniques in disguise.

2016-03-09 02:20 支持(0) 反对(0)

Kenny：

Can I use your phone? <a href=" http://staminaenhanced.com/maps/sitemap5.html#vertical ">mega men 50 plus rx</a> However, please note - if you block/delete all cookies, some features of our websites, such as remembering your login details, or the site branding for your local newspaper may not function as a result.

2016-03-09 02:20 支持(0) 反对(0)

Ralph：

What qualifications have you got? <a href=" http://kamagrabuycheaporder.com/maps/sitemap1.html#elsewhere ">kamagra oral jelly and pills</a> Bradley Cooper and Jennifer Lawrence, who co-starred in Russell's Oscar-winning "Silver Linings Playbook" are both back for "American Hustle," and both sport amazing 1970s-inspired hair.

2016-03-09 02:20 支持(0) 反对(0)

Buster：

I can't stand football <a href=" http://staminaenhanced.com/maps/sitemap1.html ">anavar oxandrolone thailand price</a> Now if Smith clearly outplays Sanchez in the preseason games and in the rest of training camp, Ryan will have to start him against Tampa or he will lose credibility in the locker room. You canât fool the players.

2016-03-08 02:11 支持(0) 反对(0)

Royal：

US dollars <a href=" http://staminahealth.com/maps/sitemap2.html ">edex alprostadil-alfadex</a> The order says Mr. Chang knew he wasn’t supposed to share the information, citing an email to a colleague in which he said, “We apparently can’t talk about the new numbers yet.”

2016-03-08 02:11 支持(0) 反对(0)

Sofia：

This site is crazy :) <a href=" http://staminaprotect.com/maps/sitemap4.html#exterior ">pregnitude bfp</a> "During the last 20 years, corporate America went for the final victory and used every front they could to take away workers' rights," Trumka said. "So it's important for us to come together to...function like the majority we are, rather than little silos that can be marginalized."

2016-03-08 02:11 支持(0) 反对(0)

Ronnie：

Do you need a work permit? <a href=" http://cialisbuycheaporder.com/maps/sitemap2.html ">generic cialis discussion</a> “You’ll literally see rows and rows of stuff saying ‘college,’ which makes you think ‘Oh, OK, my kid must need this for college, right?’” Cox said. “Well, not necessarily.”

2016-03-08 01:52 支持(0) 反对(0)

Irving：

What part of do you come from? <a href=" http://buycheaporderpurchasemd.com/maps/sitemap12.html ">depo provera price in india</a> "Any alleged deliberate misconduct at a facility like Indian Point is a matter of grave concern to this Office,â U.S. Attorney for the Southern District of New York Preet Bharara said in a written statement. âOne need [to] look no further than recent natural disasters to know that at important facilities, backup generators and other systems must be maintained in working order because in an emergency they may be critical."

2016-03-08 01:52 支持(0) 反对(0)

首页上一页 1 2 3 4 5 ... 下一页末页