1 page.title=Hello, World 2 @jd:body 3 4 <div id="qv-wrapper"> 5 <div id="qv"> 6 <h2></h2> 7 <ol> 8 <li><a href="#avd">AVD </a></li> 9 <li><a href="#create"></a></li> 10 <li><a href="#ui">UI </a></li> 11 <li><a href="#run"></a></li> 12 <li><a href="#upgrading">UI XML </a></li> 13 <li><a href="#debugging"></a></li> 14 <li><a href="#noeclipse">Eclipse </a></li> 15 </ol> 16 </div> 17 </div> 18 19 <p>Hello, WorldAndroid Eclipse </p> 20 21 <p>Eclipse <a href="{@docRoot}guide/developing/other-ide.html">Developing in Other IDEs</a>Eclipse </p> 22 23 <p> SDK Eclipse ADT <a href="{@docRoot}sdk/installing.html">Installing the Android SDK</a></p> 24 25 <h2 id="avd">AVD </h2> 26 27 <div class="sidebox-wrapper"> 28 <div class="sidebox"> 29 <p>AVD <a href="{@docRoot}guide/developing/tools/avd.html">Android </a> </p> 30 </div> 31 </div> 32 33 <p> Android Android AVDAVD </p> 34 35 <p>AVD Android SDK android SDK <code>tools/</code> 36 <pre> 37 android create avd --target 2 --name my_avd 38 </pre> 39 40 <p> No AVD Android 1.5 my_avd AVD AVD </p> 41 42 <p> <code>--target</code> <code>--name</code> AVD </p> 43 44 45 <h2 id="create"> Android </h2> 46 47 <p>AVD Eclipse Android </p> 48 49 <ol> 50 <li>Eclipse <strong>[[]File] > [[]New] > [[]Project]</strong> 51 <p>ADT Plugin for Eclipse AndroidAndroid Android Project1 Android Android XML File</p> 52 </li> 53 54 <li>Android Android Project[[]<strong>Next</strong>] <br/><a href="images/hello_world_0.png"><img src="images/hello_world_0.png" style="height:230px" alt="" /></a> 55 </li> 56 57 <li> 58 <ul> 59 <li><em>Project name:</em> HelloAndroid</li> 60 <li><em>Application name:</em> Hello, Android</li> 61 <li><em>Package name:</em> com.example.helloandroid </li> 62 <li><em>Create Activity:</em> HelloAndroid</li> 63 <li><em>SDK Min SDK Version:</em> 2</li> 64 </ul> 65 <p>[[]<strong>Finish</strong>] </p> 66 67 <a href="images/hello_world_1.png"><img src="images/hello_world_1.png" style="height:230px" alt="" /></a> 68 69 <p></p> 70 71 <dl> 72 <dt><em>Project Name</em></dt> 73 <dd>Eclipse </dd> 74 <dt><em>Application Name</em></dt> 75 <dd> Android </dd> 76 <dt><em>Package Name</em></dt> 77 <dd> Java Activity 78 <p> Android com.example </p></dd> 79 <dt><em>Create Activity</em></dt> 80 <dd> Android {@link android.app.Activity} UI </dd> 81 <dt><em>SDK Min SDK Version</em></dt> 82 <dd> API API API API 2 Android 1.1 Android Android SDK API API API <em></em></dd> 83 </dl> 84 85 <p><em></em>: [[]SDK Min SDK Version] </p> 86 87 <p class="note"> Android 1.1 Android 1.1 AVD Android 1.5 Android 1.1 1.5 </p> 88 </li> 89 </ol> 90 91 <p> Android Package Explorer<em>HelloAndroid > src > com.example.helloandroid</em> <code>HelloAndroid.java</code> </p> 92 93 <pre> 94 package com.example.helloandroid; 95 96 import android.app.Activity; 97 import android.os.Bundle; 98 99 public class HelloAndroid extends Activity { 100 /** Called when the activity is first created. */ 101 @Override 102 public void onCreate(Bundle savedInstanceState) { 103 super.onCreate(savedInstanceState); 104 setContentView(R.layout.main); 105 } 106 }</pre> 107 108 <p> {@link android.app.Activity} Activity 1 1 Android {@link android.app.Activity#onCreate(Bundle) onCreate()} UI </p> 109 110 <p> </p> 111 112 113 <h2 id="ui">UI </h2> 114 115 <p> HelloAndroid </p> 116 117 <pre> 118 package com.android.helloandroid; 119 120 import android.app.Activity; 121 import android.os.Bundle; 122 <strong>import android.widget.TextView;</strong> 123 124 public class HelloAndroid extends Activity { 125 /** Called when the activity is first created. */ 126 @Override 127 public void onCreate(Bundle savedInstanceState) { 128 super.onCreate(savedInstanceState); 129 <strong>TextView tv = new TextView(this); 130 tv.setText("Hello, Android"); 131 setContentView(tv);</strong> 132 } 133 }</pre> 134 135 <p class="note"><strong>:</strong> <strong>Ctrl+Shift+O</strong>Mac <strong>+Shift+O</strong> Eclipse </p> 136 137 <p>Android Views{@link android.view.View} UI View {@link android.widget.TextView} </p> 138 139 <p> TextView Android {@link android.content.Context} Context Activity Context HelloAndroid Activity Context <code>this</code> Context TextView </p> 140 141 <p>{@link android.widget.TextView setText(CharSequence) setText()} </p> 142 143 <p> Activity UI TextView {@link android.app.Activity#setContentView(View) setContentView()} Activity UI </p> 144 145 <p>Android Hello, World</p> 146 147 148 <h2 id="run"></h2> 149 150 <p>Eclipse </p> 151 152 <ol> 153 <li><strong>[[]] > [[]]</strong> </li> 154 <li>Android Application</li> 155 </ol> 156 157 <div class="sidebox-wrapper"> 158 <div class="sidebox"> 159 <p>Eclipse <a href="{@docRoot}guide/developing/eclipse-adt.html#RunConfig">ADT Eclipse </a></p> 160 </div> 161 </div> 162 163 <p>Eclipse ADT Android </p> 164 165 <a href="images/hello_world_5.png"><img src="images/hello_world_5.png" style="height:230px" alt="" /></a> 166 167 <p>Hello, Android Eclipse <code>res/values/strings.xml</code> <code>AndroidManifest.xml</code> TextView </p> 168 169 <p>Hello WorldAndroid </p> 170 171 172 <h2 id="upgrading">UI XML </h2> 173 174 <p>Hello, World UI UI UI </p> 175 176 <p>Android XML UI XML </p> 177 178 <pre><?xml version="1.0" encoding="utf-8"?> 179 <TextView xmlns:android="http://schemas.android.com/apk/res/android"; 180 android:layout_width="fill_parent" 181 android:layout_height="fill_parent" 182 android:text="@string/hello"/></pre> 183 184 <p>Android XML XML View View 1 XML {@link android.view.View} View UI UI Web </p> 185 186 <p> XML <code>TextView</code> View 1 4 XML 4 </p> 187 188 <table> 189 <tbody> 190 <tr> 191 <th> 192 193 </th> 194 <th> 195 196 </th> 197 </tr> 198 <tr> 199 <td> 200 <code>xmlns:android</code> 201 </td> 202 <td> 203 Android Android XML Android <br> 204 </td> 205 </tr> 206 <tr> 207 <td> 208 <code>android:layout_width</code> 209 </td> 210 <td> 211 View View fill_parent<br> 212 </td> 213 </tr> 214 <tr> 215 <td> 216 <code>android:layout_height</code> 217 </td> 218 <td> 219 android:layout_width 220 </td> 221 </tr> 222 <tr> 223 <td> 224 <code>android:text</code> 225 </td> 226 <td> 227 TextView <em>hello</em> <em>res/values/strings.xml</em> <a href="{@docRoot}guide/topics/resources/resources-i18n.html"></a> 228 </td> 229 </tr> 230 </tbody> 231 </table> 232 233 234 <p> XML <code>res/layout/</code> resresources </p> 235 <div class="sidebox-wrapper"> 236 <div class="sidebox"> 237 <h2></h2> 238 <p> XML /res/layout-land Android </p> 239 </div> 240 </div> 241 242 <p>Eclipse 1 main.xmlHello World Android XML XML </p> 243 244 <ol> 245 <li>Eclipse Package Explorer<code>/res/layout/</code> <code>main.xml</code> XML main.xml XML 246 247 <pre><?xml version="1.0" encoding="utf-8"?> 248 <TextView xmlns:android="http://schemas.android.com/apk/res/android"; 249 android:layout_width="fill_parent" 250 android:layout_height="fill_parent" 251 android:text="@string/hello"/></pre> 252 <p></p> 253 </li> 254 255 <li><code>res/values/</code> <code>strings.xml</code> Eclipse ADT <em>hello</em> <em>app_name</em> 2 <em>hello</em> Hello, Android! I am a string resource! 256 <pre> 257 <?xml version="1.0" encoding="utf-8"?> 258 <resources> 259 <string name="hello">Hello, Android! I am a string resource!</string> 260 <string name="app_name">Hello, Android</string> 261 </resources> 262 </pre> 263 </li> 264 265 <li><code>HelloAndroid</code> XML 266 <pre> 267 package com.example.helloandroid; 268 269 import android.app.Activity; 270 import android.os.Bundle; 271 272 public class HelloAndroid extends Activity { 273 /** Called when the activity is first created. */ 274 @Override 275 public void onCreate(Bundle savedInstanceState) { 276 super.onCreate(savedInstanceState); 277 setContentView(R.layout.main); 278 } 279 }</pre> 280 281 <p>R.layout.main</p> 282 283 <p>View <code>setContentView()</code> <code>R.layout.main</code> <code>/res/layout/main.xml</code> Eclipse R.java Eclipse Ant R.java R </p> 284 </li> 285 </ol> 286 287 <p> <strong>[[]Run] > [[]Run History] > [[]Android Activity]</strong> TextView 2 </p> 288 289 <p class="note"><strong>:</strong> <strong>Ctrl+F11</strong>Mac <strong>+Shift+F11</strong></p> 290 291 <p><a href="{@docRoot}guide/topics/fundamentals.html"></a>Android <a href="{@docRoot}guide/index.html"> </a><em> </em> </p> 292 293 294 <div class="special"> 295 <h3>R </h3> 296 <p>Eclipse <code>R.java</code> <code>gen/</code> Java Generated Java Files</p> 297 298 <pre> 299 package com.example.helloandroid; 300 301 public final class R { 302 public static final class attr { 303 } 304 public static final class drawable { 305 public static final int icon=0x7f020000; 306 } 307 public static final class layout { 308 public static final int main=0x7f030000; 309 } 310 public static final class string { 311 public static final int app_name=0x7f040001; 312 public static final int hello=0x7f040000; 313 } 314 } 315 </pre> 316 317 <p> <code>R.java</code> Eclipse </p> 318 319 <p> 16 layoutmainEclipse main.xml XML <code>res/values/string.xml</code> <code>res/drawable/</code> <code>R.java</code> </p> 320 <p>Eclipse Ant </p> 321 <p><em></em></p> 322 </div> 323 324 <h2 id="debugging"></h2> 325 326 <p>Android Plugin for Eclipse Eclipse HelloAndroid </p> 327 328 <pre> 329 package com.android.helloandroid; 330 331 import android.app.Activity; 332 import android.os.Bundle; 333 334 public class HelloAndroid extends Activity { 335 /** Called when the activity is first created. */ 336 @Override 337 public void onCreate(Bundle savedInstanceState) { 338 super.onCreate(savedInstanceState); 339 Object o = null; 340 o.toString(); 341 setContentView(R.layout.main); 342 } 343 }</pre> 344 345 <p> NullPointerException </p> 346 347 <a href="images/hello_world_8.png"><img src="images/hello_world_8.png" style="height:230px" alt="" /></a> 348 349 <p> </p> 350 351 <p> <code>Object o = null;</code> <strong>[[]Run] > [[] Debug History] > [[]Hello, Android]</strong> Eclipse Debug Perspective</p> 352 353 <a href="images/hello_world_9.png"><img src="images/hello_world_9.png" style="height:230px" alt="" /></a> 354 355 356 <h2 id="noeclipse">Eclipse </h2> 357 358 <p>Eclipse Eclipse Eclipse </p> 359 360 <p>Android Plugin for Eclipse Android SDK aaptadbddms <a href="{@docRoot}guide/developing/tools/index.html"></a>Ant </p> 361 362 <p>Android SDK android Ant <code>build.xml</code> </p> 363 364 <p>Eclipse HelloAndroid </p> 365 366 <pre> 367 android create project \ 368 --package com.android.helloandroid \ 369 --activity HelloAndroid \ 370 --target 2 \ 371 --path <em><path-to-your-project></em>/HelloAndroid 372 </pre> 373 374 <p><em>path</em> </p> 375 376 <p>SDK <a href="{@docRoot}guide/developing/other-ide.html">Developing in Other IDEs</a></p> 377
