挑战练习参考答案.zip_android 源码_android开发

<html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta charset="utf-8"> <meta name="generator" content="pdf2htmlEX"> <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"> <link rel="stylesheet" href="https://static.pudn.com/base/css/base.min.css"> <link rel="stylesheet" href="https://static.pudn.com/base/css/fancy.min.css"> <link rel="stylesheet" href="https://static.pudn.com/prod/directory_preview_static/62522dd774bc5c0105bbfd02/raw.css"> <script src="https://static.pudn.com/base/js/compatibility.min.js"></script> <script src="https://static.pudn.com/base/js/pdf2htmlEX.min.js"></script> <script> try{ pdf2htmlEX.defaultViewer = new pdf2htmlEX.Viewer({}); }catch(e){} </script> <title></title> </head> <body> <div id="sidebar" style="display: none"> <div id="outline"> </div> </div> <div id="pf1" class="pf w0 h0" data-page-no="1"><div class="pc pc1 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/62522dd774bc5c0105bbfd02/bg1.jpg"><div class="t m0 x1 h2 y1 ff1 fs0 fc0 sc0 ls0 ws0"> </div><div class="t m0 x1 h2 y2 ff1 fs0 fc0 sc0 ls0 ws0"> </div><div class="t m0 x1 h2 y3 ff1 fs0 fc0 sc0 ls0 ws0"> </div><div class="t m0 x1 h3 y4 ff2 fs1 fc0 sc0 ls0 ws0"> </div><div class="t m0 x2 h4 y5 ff3 fs1 fc0 sc1 ls0 ws0">And<span class="_ _0"></span>ro<span class="_ _0"></span>id<span class="_ _0"></span> </div><div class="t m0 x3 h4 y6 ff4 fs1 fc0 sc1 ls1 ws0">编程<span class="ls0">权威<span class="_ _0"></span>指南<span class="_ _0"></span><span class="ff3"> </span></span></div><div class="t m0 x4 h4 y7 ff4 fs1 fc0 sc1 ls0 ws0">挑战<span class="_ _0"></span>练习<span class="_ _0"></span>参考答案<span class="_ _1"></span><span class="ff3"> </span></div><div class="t m0 x5 h5 y8 ff2 fs2 fc0 sc0 ls0 ws0"> </div><div class="t m0 x5 h5 y9 ff2 fs2 fc0 sc0 ls0 ws0"> </div><div class="t m0 x5 h5 ya ff2 fs2 fc0 sc0 ls0 ws0"> </div><div class="t m0 x5 h5 yb ff2 fs2 fc0 sc0 ls0 ws0"> </div><div class="t m0 x5 h5 yc ff2 fs2 fc0 sc0 ls0 ws0"> </div><div class="t m0 x5 h5 yd ff2 fs2 fc0 sc0 ls0 ws0"> </div><div class="t m0 x5 h5 ye ff2 fs2 fc0 sc0 ls0 ws0"> </div><div class="t m0 x5 h5 yf ff2 fs2 fc0 sc0 ls0 ws0"> </div><div class="t m0 x5 h5 y10 ff2 fs2 fc0 sc0 ls0 ws0"> </div><div class="t m0 x5 h5 y11 ff2 fs2 fc0 sc0 ls0 ws0"> </div><div class="t m0 x6 h6 y12 ff5 fs3 fc0 sc0 ls0 ws0">亦可以访问论坛<span class="_ _2"> </span><span class="ff2 fc1">http://forum<span class="_ _3"></span>s.bignerdranch.com<span class="_ _3"></span>/viewforum.php?f=<span class="_ _3"></span>395</span></div><div class="t m0 x7 h6 y13 ff5 fs3 fc0 sc0 ls0 ws0">寻求在线帮助<span class="ff2"> </span></div><a class="l" rel='nofollow' onclick='return false;'><div class="d m1"></div></a><a class="l" rel='nofollow' onclick='return false;'><div class="d m1"></div></a></div><div class="pi" data-data='{"ctm":[1.611792,0.000000,0.000000,1.611792,0.000000,0.000000]}'></div></div> </body> </html>

<div id="pf2" class="pf w0 h0" data-page-no="2"><div class="pc pc2 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/62522dd774bc5c0105bbfd02/bg2.jpg"><div class="t m0 x8 h7 y14 ff2 fs4 fc0 sc0 ls0 ws0">Android<span class="_"> </span><span class="ff5">编程权威指南</span> <span class="_"> </span><span class="ff5">挑战练习参考答案</span> </div><div class="t m0 x9 h7 y15 ff2 fs4 fc0 sc0 ls0 ws0">1 </div><div class="t m0 x1 h7 y16 ff2 fs4 fc0 sc0 ls0 ws0"> </div><div class="t m0 xa h8 y17 ff5 fs5 fc2 sc0 ls0 ws0">目录<span class="ff6"> </span></div><div class="t m0 x1 h5 y2 ff2 fs2 fc0 sc0 ls0 ws0">2.8 <span class="_"> </span><span class="ff5">挑战练习一<span class="_ _3"></span>：为<span class="_ _4"> </span><span class="ff2">T<span class="_ _5"></span>extV<span class="_ _5"></span>iew<span class="_ _4"> </span><span class="ff5">添加监<span class="_ _3"></span>听器<span class="ff2"> <span class="_ _5"></span>.................................................................................. <span class="_ _6"></span>2<span class="ff7"> </span></span></span></span></span></div><div class="t m0 x1 h5 y18 ff2 fs2 fc0 sc0 ls0 ws0">2.9 <span class="_"> </span><span class="ff5">挑战练习二<span class="_ _3"></span>：添加后退按钮<span class="_ _3"></span><span class="ff2"> <span class="_ _7"></span>.................................................................................................... <span class="_ _7"></span>2<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y3 ff2 fs2 fc0 sc0 ls0 ws0">2.10 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>三：从按钮<span class="_ _3"></span>到图标按钮<span class="ff2"> <span class="_ _7"></span>.......................................................................................... <span class="_ _7"></span>3<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y19 ff2 fs2 fc0 sc0 ls0 ws0">5.5 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span><span class="ff2"> <span class="_ _8"></span>.................................................................................................................................... <span class="_ _7"></span>4<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y1a ff2 fs2 fc0 sc0 ls0 ws0">6.4 <span class="_"> </span><span class="ff5">挑战练习：<span class="_ _3"></span>报告编译版本<span class="_ _3"></span><span class="ff2"> <span class="_ _7"></span>........................................................................................................ <span class="_ _7"></span>6<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y1b ff2 fs2 fc0 sc0 ls0 ws0">8.6 <span class="_"> </span><span class="ff5">挑战练习：<span class="_ _3"></span>日期格式化<span class="ff2"> <span class="_ _8"></span>............................................................................................................ <span class="_ _7"></span>7<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y1c ff2 fs2 fc0 sc0 ls0 ws0">12.3 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：更多对话<span class="_ _3"></span>框<span class="ff2"> <span class="_ _7"></span>.......................................................................................................... <span class="_ _7"></span>7<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y1d ff2 fs2 fc0 sc0 ls0 ws0">13.6 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：暂停音频<span class="_ _3"></span>播放<span class="ff2"> <span class="_ _7"></span>.................................................................................................... <span class="_ _7"></span>13<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y1e ff2 fs2 fc0 sc0 ls0 ws0">13.8 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：在<span class="_ _4"> </span><span class="ff2">HelloMoon<span class="_"> </span></span>应<span class="_ _3"></span>用中播放视频<span class="_ _3"></span><span class="ff2"> ....................................................................... <span class="_ _7"></span>15<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y1f ff2 fs2 fc0 sc0 ls0 ws0">16.4 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：用于列表<span class="_ _3"></span>的空视图<span class="ff2"> <span class="_ _7"></span>............................................................................................ <span class="_ _7"></span>16<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y20 ff2 fs2 fc0 sc0 ls0 ws0">17.2 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：使用外部<span class="_ _3"></span>存储<span class="ff2"> <span class="_ _7"></span>.................................................................................................... <span class="_ _7"></span>18<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y21 ff2 fs2 fc0 sc0 ls0 ws0">18.5 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：在<span class="_ _4"> </span><span class="ff2">CrimeF<span class="_ _3"></span>ragment<span class="_"> </span><span class="ff5">视图中删<span class="_ _3"></span>除<span class="_ _4"> </span><span class="ff2">crime<span class="_"> </span></span>记录<span class="ff2"> <span class="_ _8"></span>...................................................... <span class="_ _7"></span>19<span class="ff7"> </span></span></span></span></span></div><div class="t m0 x1 h5 y22 ff2 fs2 fc0 sc0 ls0 ws0">18.7 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：使用<span class="_ _4"> </span><span class="ff2">ActionBarS<span class="_ _3"></span>herlock <span class="_ _6"></span>.................................................................................... <span class="_ _6"></span>19<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y23 ff2 fs2 fc0 sc0 ls0 ws0">20.6 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：<span class="ff2">Crim<span class="_ _3"></span>e<span class="_"> </span><span class="ff5">照片的显示方向</span> <span class="_ _7"></span>..................................................................................... <span class="_ _7"></span>19<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y24 ff2 fs2 fc0 sc0 ls0 ws0">20.7 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：删除照片<span class="_ _3"></span><span class="ff2"> <span class="_ _7"></span>............................................................................................................ <span class="_ _7"></span>23<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y25 ff2 fs2 fc0 sc0 ls0 ws0">21.5 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：又一个隐<span class="_ _3"></span>式<span class="_ _4"> </span><span class="ff2">intent <span class="_ _8"></span>.............................................................................................. <span class="_ _6"></span>25<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y26 ff2 fs2 fc0 sc0 ls0 ws0">23.6 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：应用图标<span class="_ _3"></span>与任务重排<span class="ff2"> <span class="_ _7"></span>........................................................................................ <span class="_ _7"></span>26<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y27 ff2 fs2 fc0 sc0 ls0 ws0">24.5 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：样式的继<span class="_ _3"></span>承<span class="ff2"> <span class="_ _7"></span>........................................................................................................ <span class="_ _7"></span>28<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y28 ff2 fs2 fc0 sc0 ls0 ws0">26.8 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：分页<span class="ff2"> <span class="_ _8"></span>.................................................................................................................... <span class="_ _7"></span>28<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y29 ff2 fs2 fc0 sc0 ls0 ws0">27.7 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：预加载以<span class="_ _3"></span>及缓存<span class="ff2"> <span class="_ _7"></span>................................................................................................ <span class="_ _7"></span>30<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y2a ff2 fs2 fc0 sc0 ls0 ws0">28.4 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span><span class="ff2"> <span class="_ _8"></span>................................................................................................................................ <span class="_ _7"></span>32<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y2b ff2 fs2 fc0 sc0 ls0 ws0">32.5 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：设备旋转<span class="_ _3"></span>问题<span class="ff2"> <span class="_ _7"></span>.................................................................................................... <span class="_ _7"></span>35<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y2c ff2 fs2 fc0 sc0 ls0 ws0">34.6 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：识别当前<span class="_ _3"></span>跟踪的旅程<span class="ff2"> <span class="_ _7"></span>........................................................................................ <span class="_ _7"></span>37<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y2d ff2 fs2 fc0 sc0 ls0 ws0">36.5 <span class="_"> </span><span class="ff5">挑战练习<span class="_ _3"></span>：实时数据<span class="_ _3"></span>更新<span class="ff2"> <span class="_ _7"></span>.................................................................................................... <span class="_ _7"></span>38<span class="ff7"> </span></span></span></div><div class="t m0 x1 h5 y2e ff2 fs2 fc0 sc0 ls0 ws0"> </div><a class="l" rel='nofollow' onclick='return false;'><div class="d m1"></div></a><a class="l" rel='nofollow' onclick='return false;'><div class="d m1"></div></a><a class="l" rel='nofollow' onclick='return false;'><div class="d m1"></div></a><a class="l" rel='nofollow' onclick='return false;'><div class="d m1"></div></a><a class="l" rel='nofollow' onclick='return false;'><div class="d m1"></div></a><a class="l" rel='nofollow' onclick='return false;'><div class="d m1"></div></a><a class="l" rel='nofollow' onclick='return false;'><div class="d m1"></div></a><a class="l" rel='nofollow' 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<div id="pf3" class="pf w0 h0" data-page-no="3"><div class="pc pc3 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/62522dd774bc5c0105bbfd02/bg3.jpg"><div class="t m0 x8 h7 y14 ff2 fs4 fc0 sc0 ls0 ws0">Android<span class="_"> </span><span class="ff5">编程权威指南</span> <span class="_"> </span><span class="ff5">挑战练习参考答案</span> </div><div class="t m0 x9 h7 y15 ff2 fs4 fc0 sc0 ls0 ws0">2 </div><div class="t m0 x1 h7 y16 ff2 fs4 fc0 sc0 ls0 ws0"> </div><div class="t m0 x1 h9 y2f ff1 fs5 fc0 sc0 ls0 ws0">2.8 <span class="_"> </span><span class="ff5 sc1 ls1">挑战练习<span class="ls0">一：<span class="_ _0"></span>为<span class="_ _9"> </span></span></span>TextView<span class="_ _a"> </span><span class="ff5 sc1 ls1">添加监听器</span> </div><div class="t m0 x1 ha y30 ff5 fs2 fc0 sc1 ls0 ws0">代码清单<span class="_ _4"> </span><span class="ff1 sc0">2-1 <span class="_"> </span></span>为<span class="_ _4"> </span><span class="ff1 sc0">T<span class="_ _5"></span>extV<span class="_ _5"></span>iew<span class="_"> </span><span class="ff5 sc1">添加监听器（</span>Qui<span class="_ _3"></span>zActivity<span class="_ _5"></span>.java<span class="_ _3"></span><span class="ff5 sc1">）<span class="ff1 sc0"> </span></span></span></div><div class="t m0 x1 hb y31 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span><span class="fc3 ls2">mQuestionTextView<span class="_ _0"></span><span class="fc0 ls0"> <span class="ls2">= </span></span></span></div><div class="t m0 x1 hb y32 ff8 fs6 fc0 sc0 ls2 ws0">(TextView)findViewById(R.id.<span class="ff9 fc3">question_text_view</span>);<span class="ls0"> </span></div><div class="t m0 x1 hc y33 ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc3 ls2">mQuestionTextView<span class="fc0">.setOnClickListener(<span class="fc4">new</span><span class="ls0"> <span class="_ _c"></span><span class="ls2">View.OnClickListener() </span></span></span></span></div><div class="t m0 x1 hc y34 ffa fs6 fc0 sc0 ls0 ws0">{ </div><div class="t m0 x1 hc y35 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc5 ls2">@Override</span> </div><div class="t m0 x1 hc y36 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc4 ls2">public</span> <span class="fc4 ls2">void</span> <span class="ls2">onClick(View v) {</span> </div><div class="t m0 x1 hc y37 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mCurrentIndex</span> <span class="_ _5"></span>= <span class="_ _5"></span>(<span class="fc3">mCurrentIndex<span class="_ _0"></span></span> <span class="_ _b"></span>+ <span class="_ _5"></span>1) <span class="_ _5"></span>% <span class="_ _5"></span><span class="fc3">mA<span class="_ _0"></span>nswer<span class="ls2">Key</span><span class="fc0">.</span><span class="ls2">length</span><span class="fc0">; </span></span></div><div class="t m0 x1 hc y38 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">updateQuestion();</span> </div><div class="t m0 x1 hc y39 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span>} </div><div class="t m0 x1 hc y3a ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">});</span> </div><div class="t m0 x1 h9 y3b ff1 fs5 fc0 sc0 ls0 ws0">2.9 <span class="_"> </span><span class="ff5 sc1 ls1">挑战练习二：添加后退按钮</span> </div><div class="t m0 x1 ha y3c ff5 fs2 fc0 sc1 ls0 ws0">代码清单<span class="_ _4"> </span><span class="ff1 sc0">2-2 <span class="_"> </span></span>添加字符串资源（<span class="ff1 sc0">strin<span class="_ _3"></span>gs.xml<span class="ff5 sc1">）</span> </span></div><div class="t m0 x1 hb y3d ff8 fs6 fc0 sc0 ls3 ws0"> <span class="fc6 ls0"><<span class="fc7 ls2">string</span><span class="fc0"> <span class="fc8 ls2">name</span>=<span class="ff9 fc9 ls2">"next_button"</span></span>></span><span class="ls2">Next<span class="fc6"></<span class="fc7">string</span><span class="ls0">><span class="fc0"> </span></span></span></span></div><div class="t m0 x1 hc y3e ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc6 ls0"><<span class="fc7 ls2">string</span><span class="fc0"> <span class="fc8 ls2">name</span>=<span class="ffb fc9 ls2">"prev_button"</span></span>></span><span class="ls2">Prev<span class="fc6"></<span class="fc7">string</span><span class="ls0">><span class="fc0"> </span></span></span></span></div><div class="t m0 x1 ha y3f ff5 fs2 fc0 sc1 ls0 ws0">代码清单<span class="_ _4"> </span><span class="ff1 sc0">2-3 <span class="_"> </span></span>修改布局（<span class="ff1 sc0">activi<span class="_ _3"></span>ty_quiz.xml<span class="ff5 sc1">）</span> </span></div><div class="t m0 x1 hb y40 ff8 fs6 fc6 sc0 ls0 ws0"><<span class="fc7 ls2">LinearLayout</span><span class="fc0"> <span class="_ _5"></span><span class="fc8"> </span></span></div><div class="t m0 x1 hb y41 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffc">…</span> </div><div class="t m0 xb hb y42 ff8 fs6 fc6 sc0 ls0 ws0"><<span class="fc7 ls2">TextView<span class="ls0"> </span></span></div><div class="t m0 xb hb y43 ff8 fs6 fc7 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffc ls2">…/></span><span class="fc0"> </span></div><div class="t m0 xb hb y44 ff8 fs6 fc6 sc0 ls0 ws0"><<span class="fc7 ls2">LinearLayout<span class="ls0"> </span></span></div><div class="t m0 xb hb y45 ff8 fs6 fc7 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffc">…</span><span class="fc0"> </span></div><div class="t m0 x1 hb y46 ff8 fs6 fc0 sc0 ls3 ws0"> <span class="fc6 ls2"></<span class="fc7">LinearLayout</span><span class="ls0">><span class="fc0"> </span></span></span></div><div class="t m0 x1 hc y47 ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc6 ls0"><<span class="fc7 ls2">LinearLayout</span><span class="fc0"> </span></span></div><div class="t m0 x1 hc y48 ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:layout_width</span><span class="ls0">=<span class="ffb fc9 ls2">"wrap_content"</span> </span></div><div class="t m0 x1 hc y49 ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:layout_height</span><span class="ls0">=<span class="ffb fc9 ls2">"wrap_content"</span> </span></div><div class="t m0 x1 hc y4a ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:orientation</span><span class="ls0">=<span class="ffb fc9 ls2">"horizontal"</span> <span class="fc6">></span> </span></div><div class="t m0 x1 hc y4b ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc6 ls0"><<span class="fc7 ls2">Button</span><span class="fc0"> </span></span></div><div class="t m0 x1 hc y4c ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:id</span><span class="ls0">=<span class="ffb fc9 ls2">"@+id/prev_button"</span> </span></div><div class="t m0 x1 hc y4d ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:layout_width</span><span class="ls0">=<span class="ffb fc9 ls2">"wrap_content"</span> </span></div><div class="t m0 x1 hc y4e ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:layout_height</span><span class="ls0">=<span class="ffb fc9 ls2">"wrap_content"</span> </span></div><div class="t m0 x1 hc y4f ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:drawableLeft</span><span class="ls0">=<span class="ffb fc9 ls2">"@drawable/arrow_left"</span> </span></div><div class="t m0 x1 hc y50 ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:drawablePadding</span><span class="ls0">=<span class="ffb fc9 ls2">"4dp"</span> </span></div><div class="t m0 x1 hc y51 ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:text</span><span class="ls0">=<span class="ffb fc9 ls2">"@string/prev_button"</span> <span class="fc6 ls2">/></span> </span></div><div class="t m0 x1 hb y52 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span><span class="fc6"><<span class="_ _0"></span><span class="fc7 ls2">Button<span class="_ _3"></span><span class="fc0 ls0"> </span></span></span></div><div class="t m0 x1 hb y53 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="fc8 ls2">android:id<span class="fc0 ls0">=</span><span class="ff9 fc9">"@+id/next_button"</span><span class="fc0 ls0"> </span></span></div></div><div class="pi" data-data='{"ctm":[1.611792,0.000000,0.000000,1.611792,0.000000,0.000000]}'></div></div>

<div id="pf4" class="pf w0 h0" data-page-no="4"><div class="pc pc4 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/62522dd774bc5c0105bbfd02/bg4.jpg"><div class="t m0 x8 h7 y14 ff2 fs4 fc0 sc0 ls0 ws0">Android<span class="_"> </span><span class="ff5">编程权威指南</span> <span class="_"> </span><span class="ff5">挑战练习参考答案</span> </div><div class="t m0 x9 h7 y15 ff2 fs4 fc0 sc0 ls0 ws0">3 </div><div class="t m0 x1 h7 y16 ff2 fs4 fc0 sc0 ls0 ws0"> </div><div class="t m0 x1 hb y54 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="ffc">…<span class="ff8"> <span class="fc6 ls2">/></span> </span></span></div><div class="t m0 x1 hb y55 ff8 fs6 fc0 sc0 ls3 ws0"> <span class="fc6 ls2"></<span class="fc7">LinearLayout</span><span class="ls0">><span class="fc0"> </span></span></span></div><div class="t m0 x1 ha y56 ff5 fs2 fc0 sc1 ls0 ws0">代码清单<span class="_ _4"> </span><span class="ff1 sc0">2-4 <span class="_"> </span></span>修改<span class="_ _4"> </span><span class="ff1 sc0">QuizActivi<span class="_ _3"></span>ty<span class="ff5 sc1">（</span>QuizActivity<span class="_ _5"></span>.java<span class="ff5 sc1">）</span> </span></div><div class="t m0 x1 hb y57 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ls2">Button <span class="fc3">mNextButton</span></span>; </div><div class="t m0 x1 hc y58 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ls2">Button <span class="fc3">mPrevButton</span></span>; </div><div class="t m0 x1 hb y59 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffc">…</span> </div><div class="t m0 x1 hb y5a ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="fc5 ls2">@Override</span> </div><div class="t m0 x1 hc y5b ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffa fc4 ls2">protected</span> <span class="ffa fc4 ls2">void</span> <span class="ls2">onCreate(Bundle savedInstanceState) {</span> </div><div class="t m0 x1 hb y5c ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ffc">…</span> </div><div class="t m0 x1 hc y5d ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mNextButton<span class="fc0">.setOnClickListener(<span class="ffa fc4">new</span></span></span> <span class="ls2">View.OnClickListener() {</span> </div><div class="t m0 x1 hb y5e ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc5 ls2">@Override</span> </div><div class="t m0 x1 hc y5f ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ffa fc4 ls2">public</span> <span class="ffa fc4 ls2">void</span> <span class="ls2">onClick(View v) {</span> </div><div class="t m0 x1 hb y60 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mCurrentIndex</span> <span class="_ _5"></span>= <span class="_ _5"></span>(<span class="fc3">mCurrentIndex<span class="_ _0"></span></span> <span class="_ _b"></span>+ <span class="_ _5"></span>1) <span class="_ _5"></span>% <span class="_ _5"></span><span class="fc3">mA<span class="_ _0"></span>nswerKey<span class="fc0">.</span><span class="ls2">length</span><span class="fc0">; </span></span></div><div class="t m0 x1 hb y61 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">updateQuestion();</span> </div><div class="t m0 x1 hb y62 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span>} </div><div class="t m0 x1 hb y63 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">});</span> </div><div class="t m0 x1 hc y64 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mPrevButton</span> <span class="ls2">= (Button) findViewById(R.id.<span class="ffb fc3">prev_button</span>);</span> </div><div class="t m0 x1 hc y65 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mPrevButton<span class="fc0">.setOnClickListener(<span class="fc4">new</span></span></span> V<span class="ls2">iew.OnClickListener() {</span> </div><div class="t m0 x1 hc y66 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc5 ls2">@Override</span> </div><div class="t m0 x1 hc y67 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc4 ls2">public</span> <span class="fc4 ls2">void</span> <span class="ls2">onClick(View v) {</span> </div><div class="t m0 x1 hc y68 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mCurrentIndex</span> <span class="ls2">= (<span class="fc3">mCurrentIndex</span></span> <span class="ls2">+ <span class="fc3">mAnswerKey</span></span>.<span class="fc3 ls2">length</span> - <span class="ls2">1)</span> </div><div class="t m0 x1 hc y69 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">% <span class="fc3">mAnswerKey</span></span>.<span class="fc3 ls2">length</span>; </div><div class="t m0 x1 hc y6a ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">updateQuestion();</span> </div><div class="t m0 x1 hc y6b ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span>} </div><div class="t m0 x1 hc y6c ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">});</span> </div><div class="t m0 x1 h9 y6d ff1 fs5 fc0 sc0 ls0 ws0">2.10 <span class="_"> </span><span class="ff5 sc1 ls1">挑战练习<span class="ls0">三：<span class="_ _0"></span>从按钮<span class="_ _0"></span>到图标按钮<span class="_ _0"></span></span></span> </div><div class="t m0 x1 ha y6e ff5 fs2 fc0 sc1 ls0 ws0">代码清单<span class="_ _4"> </span><span class="ff1 sc0">2-5 <span class="_"> </span></span>修改布局（<span class="ff1 sc0">activi<span class="_ _3"></span>ty_quiz.xml<span class="ff5 sc1">）</span> </span></div><div class="t m0 x1 hc y6f ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span><span class="fc6"><<span class="_ _0"></span><span class="ffa fc7 ls2">ImageButton</span><span class="fc0"> </span></span></div><div class="t m0 x1 hb y70 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="fc8 ls2">android:id<span class="fc0 ls0">=</span><span class="ff9 fc9">"@+id/prev_button"</span><span class="fc0 ls0"> </span></span></div><div class="t m0 x1 hb y71 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="fc8 ls2">android:layout_width<span class="fc0 ls0">=</span><span class="ff9 fc9">"wrap_content"</span><span class="fc0 ls0"> </span></span></div><div class="t m0 x1 hb y72 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="fc8 ls2">android:layout_height<span class="fc0 ls0">=</span><span class="ff9 fc9">"wrap_content"</span><span class="fc0 ls0"> </span></span></div><div class="t m0 x1 hc y73 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="ffa fc8 ls2">android:drawableLeft<span class="fc0 ls0">=</span><span class="ffb fc9">"@drawable/arrow_left"</span><span class="fc0 ls0"> </span></span></div><div class="t m0 x1 hc y74 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="ffa fc8 ls2">android:drawablePadding<span class="fc0 ls0">=</span><span class="ffb fc9">"4dp"</span><span class="fc0 ls0"> </span></span></div><div class="t m0 x1 hc y75 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="ffa fc8 ls2">android:text<span class="fc0 ls0">=</span><span class="ffb fc9">"@string/prev_button"<span class="ff8 fc0 ls0"> </span></span></span></div><div class="t m0 x1 hc y76 ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:src</span><span class="ls0">=<span class="ffb fc9 ls2">"@drawable/arrow_left"</span> <span class="fc6 ls2">/></span> </span></div><div class="t m0 x1 hc y77 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span><span class="fc6"><<span class="_ _0"></span><span class="ffa fc7 ls2">ImageButton</span><span class="fc0"> </span></span></div><div class="t m0 x1 hb y78 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="fc8 ls2">android:id<span class="fc0 ls0">=</span><span class="ff9 fc9">"@+id/next_button"</span><span class="fc0 ls0"> </span></span></div><div class="t m0 x1 hb y79 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="fc8 ls2">android:layout_width<span class="fc0 ls0">=</span><span class="ff9 fc9">"wrap_content"</span><span class="fc0 ls0"> </span></span></div><div class="t m0 x1 hb y7a ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="fc8 ls2">android:layout_height<span class="fc0 ls0">=</span><span class="ff9 fc9">"wrap_content"</span><span class="fc0 ls0"> </span></span></div><div class="t m0 x1 hc y7b ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="ffa fc8 ls2">android:drawablePadding<span class="fc0 ls0">=</span><span class="ffb fc9">"4dp"</span><span class="fc0 ls0"> </span></span></div><div class="t m0 x1 hc y7c ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="ffa fc8 ls2">android:drawableRight<span class="fc0 ls0">=</span><span class="ffb fc9">"@drawable/arrow_right"</span><span class="fc0 ls0"> </span></span></div></div><div class="pi" data-data='{"ctm":[1.611792,0.000000,0.000000,1.611792,0.000000,0.000000]}'></div></div>

<div id="pf5" class="pf w0 h0" data-page-no="5"><div class="pc pc5 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/62522dd774bc5c0105bbfd02/bg5.jpg"><div class="t m0 x8 h7 y14 ff2 fs4 fc0 sc0 ls0 ws0">Android<span class="_"> </span><span class="ff5">编程权威指南</span> <span class="_"> </span><span class="ff5">挑战练习参考答案</span> </div><div class="t m0 x9 h7 y15 ff2 fs4 fc0 sc0 ls0 ws0">4 </div><div class="t m0 x1 h7 y16 ff2 fs4 fc0 sc0 ls0 ws0"> </div><div class="t m0 x1 hc y7d ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span> <span class="_ _5"></span> <span class="_ _b"></span><span class="ffa fc8 ls2">android:text<span class="fc0 ls0">=</span><span class="ffb fc9">"@string/next_button"<span class="ff8 fc0 ls0"> </span></span></span></div><div class="t m0 x1 hc y7e ffa fs6 fc0 sc0 ls3 ws0"> <span class="fc8 ls2">android:src</span><span class="ls0">=<span class="ffb fc9 ls2">"@drawable/arrow_right"</span> <span class="fc6 ls2">/></span> </span></div><div class="t m0 x1 ha y56 ff5 fs2 fc0 sc1 ls0 ws0">代码清单<span class="_ _4"> </span><span class="ff1 sc0">2-6 <span class="_"> </span></span>修改<span class="_ _4"> </span><span class="ff1 sc0">QuizActivi<span class="_ _3"></span>ty<span class="ff5 sc1">（</span>QuizActivity<span class="_ _5"></span>.java<span class="ff5 sc1">）</span> </span></div><div class="t m0 x1 hc y57 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffa ls2">ImageButton</span> <span class="fc3 ls2">mNextButton</span>; </div><div class="t m0 x1 hc y58 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffa ls2">ImageButton</span> <span class="fc3 ls2">mPrevButton</span>; </div><div class="t m0 x1 hb y59 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffc">…</span> </div><div class="t m0 x1 hb y5a ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="fc5 ls2">@Override</span> </div><div class="t m0 x1 hc y5b ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffa fc4 ls2">protected</span> <span class="ffa fc4 ls2">void</span> <span class="ls2">onCreate(Bundle savedInstanceState) {</span> </div><div class="t m0 x1 hb y5c ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ffc">…</span> </div><div class="t m0 x1 hc y7f ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mNextButton</span> <span class="ls2">= (<span class="ffa">ImageButton</span>) findViewById(R.id.<span class="ff9 fc3">next_button</span>);</span> </div><div class="t m0 x1 hb y5e ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ffc">…</span> </div><div class="t m0 x1 hc y80 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mPrevButton</span> <span class="ls2">= (<span class="ffa">ImageButton</span>) findViewById(R.id.<span class="ff9 fc3">prev_button</span>);</span> </div><div class="t m0 x1 h9 y81 ff1 fs5 fc0 sc0 ls0 ws0">5.5 <span class="_"> </span><span class="ff5 sc1 ls1">挑战练习</span> </div><div class="t m0 x1 ha y82 ff5 fs2 fc0 sc1 ls0 ws0">代码清单<span class="_ _4"> </span><span class="ff1 sc0">5-1 <span class="_"> </span></span>解决旋转<span class="_ _4"> </span><span class="ff1 sc0">CheatActivi<span class="_ _3"></span>ty<span class="_"> </span><span class="ff5 sc1">问题（</span>Cheat<span class="_ _3"></span>Activity<span class="_ _5"></span>.java<span class="ff5 sc1">）</span> </span></div><div class="t m0 x1 hc y83 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffa fc4 ls2">public</span> <span class="ffa fc4 ls2">static</span> <span class="ffa fc4 ls2">final</span> <span class="ls2">String <span class="ff9 fc3">EXTRA_ANSWER_SHOWN</span></span> = </div><div class="t m0 x1 hb y84 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc9 ls2">"com.bignerdranch.android.geoquiz.answer_shown"</span>; </div><div class="t m0 x1 hc y85 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="fc4 ls2">private</span> <span class="fc4 ls2">static</span> <span class="fc4 ls2">final</span> <span class="ls2">String <span class="ffb fc3">KEY_IS_CHEAT</span></span> <span class="ls2">= <span class="fc9">"isCheat"</span></span>; </div><div class="t m0 x1 hc y86 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffa fc4 ls2">private</span> <span class="ffa fc4 ls2">boolean</span> <span class="fc3 ls2">mAnswerIsTrue</span>; </div><div class="t m0 x1 hc y87 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="fc4 ls2">private</span> <span class="fc4 ls2">boolean</span> <span class="fc3 ls2">mIsCheat</span>; </div><div class="t m0 x1 hb y88 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffc">…</span> </div><div class="t m0 x1 hb y89 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="fc5 ls2">@Override</span> </div><div class="t m0 x1 hc y8a ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="ffa fc4 ls2">protected</span> <span class="ffa fc4 ls2">void</span> <span class="ls2">onCreate(Bundle savedInstanceState) {</span> </div><div class="t m0 x1 hb y8b ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ffc">…</span> </div><div class="t m0 x1 hc y8c ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mShowAnswer<span class="fc0">.setOnClickListener(<span class="ffa fc4">new</span></span></span> <span class="ls2">View.OnClickListener() {</span> </div><div class="t m0 x1 hb y8d ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ffc">…</span> </div><div class="t m0 x1 hb y8e ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">});</span> </div><div class="t m0 x1 hc y8f ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc4 ls2">if</span> <span class="ls2">(savedInstanceState != <span class="fc4">null</span></span> </div><div class="t m0 x1 hc y90 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">&& savedInstanceState.getBoolean(<span class="ffb fc3">KEY_IS_CHEAT</span>)) {</span> </div><div class="t m0 x1 hc y91 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc4 ls2">if</span> (<span class="fc3 ls2">mAnswerIsTrue<span class="fc0">) {</span></span> </div><div class="t m0 x1 hc y92 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mAnswerTextView<span class="fc0">.setText(R.string.</span><span class="ffb">true_button</span><span class="fc0">);</span></span> </div><div class="t m0 x1 hc y93 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">} <span class="fc4">else</span></span> { </div><div class="t m0 x1 hc y73 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mAnswerTextView<span class="fc0">.setText(R.string.</span><span class="ffb">false_button</span><span class="fc0">);</span></span> </div><div class="t m0 x1 hc y94 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span>} </div><div class="t m0 x1 hc y95 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">setAnswerShownResult(<span class="fc4">true</span>);</span> </div><div class="t m0 x1 hc y96 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc3 ls2">mIsCheat</span> <span class="ls2">= <span class="fc4">true</span></span>; </div><div class="t m0 x1 hc y77 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span>} </div><div class="t m0 x1 hb y97 ff8 fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span>} </div><div class="t m0 x1 hc y98 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="fc5 ls2">@Override</span> </div><div class="t m0 x1 hc y99 ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span><span class="fc4 ls2">protected</span> <span class="fc4 ls2">void</span> <span class="ls2">onSaveInstanceState(Bundle outState) {</span> </div><div class="t m0 x1 hc y9a ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="fc4 ls2">super<span class="fc0">.onSaveInstanceState(outState);</span></span> </div><div class="t m0 x1 hc y7c ffa fs6 fc0 sc0 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _d"> </span><span class="ls2">outState.putBoolean(<span class="ffb fc3">KEY_IS_CHEAT</span>, <span class="fc3">mIsCheat</span>);</span> </div></div><div class="pi" data-data='{"ctm":[1.611792,0.000000,0.000000,1.611792,0.000000,0.000000]}'></div></div>