1 page.title=Activity 2 page.tags=Activity, Intent 3 @jd:body 4 5 <div id="qv-wrapper"> 6 <div id="qv"> 7 <h2></h2> 8 <ol> 9 <li><a href="#Creating"> Activity</a> 10 <ol> 11 <li><a href="#UI"></a></li> 12 <li><a href="#Declaring"> Activity</a></li> 13 </ol> 14 </li> 15 <li><a href="#StartingAnActivity"> Activity</a> 16 <ol> 17 <li><a href="#StartingAnActivityForResult"> Activity </a></li> 18 </ol> 19 </li> 20 <li><a href="#ShuttingDown"> Activity</a></li> 21 <li><a href="#Lifecycle"> Activity </a> 22 <ol> 23 <li><a href="#ImplementingLifecycleCallbacks"></a></li> 24 <li><a href="#SavingActivityState"> Activity </a></li> 25 <li><a href="#ConfigurationChanges"></a></li> 26 <li><a href="#CoordinatingActivities"> Activity</a></li> 27 </ol> 28 </li> 29 </ol> 30 31 <h2></h2> 32 <ol> 33 <li>{@link android.app.Activity}</li> 34 </ol> 35 36 <h2></h2> 37 <ol> 38 <li><a href="{@docRoot}guide/components/tasks-and-back-stack.html"></a> 39 </li> 40 </ol> 41 42 </div> 43 </div> 44 45 46 47 <p>{@link android.app.Activity} 48 49 Activity 50 51 </p> 52 53 <p> Activity 54 Activity Activity Activity 55 Activity Activity 56 Activity Activity Activity 57 58 Activity 59 Activity 60 <em></em> 61 Activity<a href="{@docRoot}guide/components/tasks-and-back-stack.html"></a> 62 63 </p> 64 65 <p> Activity Activity Activity Activity — Activity Activity Activity Activity— 66 67 68 69 70 Activity 71 Activity 72 Activity 73 </p> 74 75 <p> Activity Activity Activity 76 77 </p> 78 79 80 81 <h2 id="Creating"> Activity</h2> 82 83 <p> Activity {@link android.app.Activity} 84 Activity Activity Activity Activity Activity 85 86 87 </p> 88 89 <dl> 90 <dt>{@link android.app.Activity#onCreate onCreate()}</dt> 91 <dd> 92 Activity Activity 93 94 {@link android.app.Activity#setContentView 95 setContentView()} Activity </dd> 96 <dt>{@link android.app.Activity#onPause onPause()}</dt> 97 <dd> Activity Activity 98 99 100 </dd> 101 </dl> 102 103 <p> Activity Activity 104 105 <a href="#Lifecycle"> Activity </a> 106 </p> 107 108 109 110 <h3 id="UI"></h3> 111 112 <p> Activity — {@link android.view.View} 113 Activity 114 115 </p> 116 117 <p> Android 118 119 {@link 120 android.view.ViewGroup} 121 {@link android.view.View} 122 {@link android.view.ViewGroup} 123 Activity </p> 124 125 <p> XML 126 Activity 127 {@link android.app.Activity#setContentView(int) setContentView()} 128 Activity UI 129 ID Activity 130 {@link android.view.View} {@link 131 android.view.View} {@link android.view.ViewGroup} 132 {@link android.view.ViewGroup} {@link android.app.Activity#setContentView(View) 133 setContentView()} </p> 134 135 <p><a href="{@docRoot}guide/topics/ui/index.html"></a></p> 136 137 138 139 <h3 id="Declaring"> Activity</h3> 140 141 <p> Activity 142 Activity <a href="{@docRoot}guide/topics/manifest/activity-element.html">{@code <activity>}</a> 143 <a href="{@docRoot}guide/topics/manifest/application-element.html">{@code <application>}</a> 144 </p> 145 146 <pre> 147 <manifest ... > 148 <application ... > 149 <activity android:name=".ExampleActivity" /> 150 ... 151 </application ... > 152 ... 153 </manifest > 154 </pre> 155 156 <p> Activity Activity Activity 157 UI 158 <a href="{@docRoot}guide/topics/manifest/activity-element.html#nm">{@code android:name}</a> 159 — Activity 160 <a href="http://android-developers.blogspot.com/2011/06/things-that-cannot-change.html">Things 161 That Cannot Change</a> 162 []</p> 163 164 <p> <a href="{@docRoot}guide/topics/manifest/activity-element.html">{@code <activity>}</a> 165 Activity </p> 166 167 168 <h4> Intent </h4> 169 170 <p><a href="{@docRoot}guide/topics/manifest/activity-element.html">{@code 171 <activity>}</a> Intent — <a href="{@docRoot}guide/topics/manifest/intent-filter-element.html">{@code 172 <Intent-filter>}</a> 173 —</p> 174 175 <p> Android SDK Activity Intent Activity launcher 176 177 Intent 178 </p> 179 180 <pre> 181 <activity android:name=".ExampleActivity" android:icon="@drawable/app_icon"> 182 <intent-filter> 183 <action android:name="android.intent.action.MAIN" /> 184 <category android:name="android.intent.category.LAUNCHER" /> 185 </intent-filter> 186 </activity> 187 </pre> 188 189 <p><a href="{@docRoot}guide/topics/manifest/action-element.html">{@code 190 <action>}</a> <a href="{@docRoot}guide/topics/manifest/category-element.html">{@code 191 <category>}</a> 192 Activity Activity</p> 193 194 <p> Activity Intent 195 Activity launcher 196 Activity Intent Intent 197 198 </p> 199 200 <p> Activity Intent Activity Intent 201 202 Intent <a href="{@docRoot}guide/topics/manifest/intent-filter-element.html">{@code 203 <Intent-filter>}</a> 204 <a href="{@docRoot}guide/topics/manifest/action-element.html">{@code 205 <action>}</a> <a href="{@docRoot}guide/topics/manifest/category-element.html">{@code 206 <category>}</a> / <a href="{@docRoot}guide/topics/manifest/data-element.html">{@code 207 <data>}</a> Activity Intent 208 </p> 209 210 <p> Activity Intent <a href="{@docRoot}guide/components/intents-filters.html"> Intent Intent </a> 211 </p> 212 213 214 215 <h2 id="StartingAnActivity"> Activity</h2> 216 217 <p> {@link android.app.Activity#startActivity 218 startActivity()} Activity {@link android.content.Intent} 219 ActivityIntent Activity Activity Activity 220 221 222 Intent Activity 223 </p> 224 225 <p> Activity 226 Activity Intent 227 Activity {@code 228 SignInActivity} Activity</p> 229 230 <pre> 231 Intent intent = new Intent(this, SignInActivity.class); 232 startActivity(intent); 233 </pre> 234 235 <p> Activity 236 Activity Activity 237 238 Intent — Intent Activity 239 240 241 Activity Intent 242 Intent 243 244 </p> 245 246 <pre> 247 Intent intent = new Intent(Intent.ACTION_SEND); 248 intent.putExtra(Intent.EXTRA_EMAIL, recipientArray); 249 startActivity(intent); 250 </pre> 251 252 <p> Intent {@link android.content.Intent#EXTRA_EMAIL} extra 253 Intent extra 254 255 Activity Activity 256 </p> 257 258 259 260 261 <h3 id="StartingAnActivityForResult"> Activity </h3> 262 263 <p> Activity {@link android.app.Activity#startActivityForResult 264 startActivityForResult()} {@link android.app.Activity#startActivity 265 startActivity()} Activity 266 Activity 267 {@link android.app.Activity#onActivityResult onActivityResult()} 268 Activity {@link 269 android.content.Intent} {@link android.app.Activity#onActivityResult onActivityResult()} 270 </p> 271 272 <p> Activity 273 Intent 274 </p> 275 276 <pre> 277 private void pickContact() { 278 // Create an intent to "pick" a contact, as defined by the content provider URI 279 Intent intent = new Intent(Intent.ACTION_PICK, Contacts.CONTENT_URI); 280 startActivityForResult(intent, PICK_CONTACT_REQUEST); 281 } 282 283 @Override 284 protected void onActivityResult(int requestCode, int resultCode, Intent data) { 285 // If the request went well (OK) and the request was PICK_CONTACT_REQUEST 286 if (resultCode == Activity.RESULT_OK && requestCode == PICK_CONTACT_REQUEST) { 287 // Perform a query to the contact's content provider for the contact's name 288 Cursor cursor = getContentResolver().query(data.getData(), 289 new String[] {Contacts.DISPLAY_NAME}, null, null, null); 290 if (cursor.moveToFirst()) { // True if the cursor is not empty 291 int columnIndex = cursor.getColumnIndex(Contacts.DISPLAY_NAME); 292 String name = cursor.getString(columnIndex); 293 // Do something with the selected contact's name... 294 } 295 } 296 } 297 </pre> 298 299 <p> Activity {@link 300 android.app.Activity#onActivityResult onActivityResult()} 301 {@code resultCode} {@link android.app.Activity#RESULT_OK} — {@code requestCode} {@link android.app.Activity#startActivityForResult 302 startActivityForResult()} 303 304 305 {@link android.content.Intent} {@code data} Activity 306 </p> 307 308 <p>{@link 309 android.content.ContentResolver} 310 {@link android.database.Cursor}<a href="{@docRoot}guide/topics/providers/content-providers.html"></a> 311 </p> 312 313 <p> Intent <a href="{@docRoot}guide/components/intents-filters.html"> Intent Intent </a> 314 </p> 315 316 317 <h2 id="ShuttingDown"> Activity</h2> 318 319 <p> Activity {@link android.app.Activity#finish 320 finish()} Activity 321 {@link android.app.Activity#finishActivity finishActivity()} Activity</p> 322 323 <p class="note"><strong></strong> Activity 324 Activity Android Activity Activity 325 326 Activity 327 328 </p> 329 330 331 <h2 id="Lifecycle"> Activity </h2> 332 333 <p> Activity 334 335 Activity Activity Activity 336 </p> 337 338 <p>Activity </p> 339 340 <dl> 341 <dt><i></i></dt> 342 <dd> Activity 343 </dd> 344 345 <dt><i></i></dt> 346 <dd> Activity Activity Activity Activity Activity 347 348 Activity Activity {@link android.app.Activity} 349 350 </dd> 351 352 <dt><i></i></dt> 353 <dd> Activity Activity Activity 354 Activity Activity {@link android.app.Activity} 355 <em></em> 356 357 </dd> 358 </dl> 359 360 <p> Activity 361 {@link android.app.Activity#finish finish()} 362 Activity 363 </p> 364 365 366 367 <h3 id="ImplementingLifecycleCallbacks"></h3> 368 369 <p> Activity 370 Activity 371 Activity 372 </p> 373 374 375 <pre> 376 public class ExampleActivity extends Activity { 377 @Override 378 public void {@link android.app.Activity#onCreate onCreate}(Bundle savedInstanceState) { 379 super.onCreate(savedInstanceState); 380 // The activity is being created. 381 } 382 @Override 383 protected void {@link android.app.Activity#onStart onStart()} { 384 super.onStart(); 385 // The activity is about to become visible. 386 } 387 @Override 388 protected void {@link android.app.Activity#onResume onResume()} { 389 super.onResume(); 390 // The activity has become visible (it is now "resumed"). 391 } 392 @Override 393 protected void {@link android.app.Activity#onPause onPause()} { 394 super.onPause(); 395 // Another activity is taking focus (this activity is about to be "paused"). 396 } 397 @Override 398 protected void {@link android.app.Activity#onStop onStop()} { 399 super.onStop(); 400 // The activity is no longer visible (it is now "stopped") 401 } 402 @Override 403 protected void {@link android.app.Activity#onDestroy onDestroy()} { 404 super.onDestroy(); 405 // The activity is about to be destroyed. 406 } 407 } 408 </pre> 409 410 <p class="note"><strong></strong> 411 </p> 412 413 <p> Activity Activity 414 </p> 415 416 <ul> 417 <li>Activity <b></b> {@link 418 android.app.Activity#onCreate onCreate()} {@link 419 android.app.Activity#onDestroy} Activity {@link android.app.Activity#onCreate onCreate()} 420 {@link android.app.Activity#onDestroy} 421 Activity 422 {@link android.app.Activity#onCreate onCreate()} 423 {@link 424 android.app.Activity#onDestroy} </li> 425 426 <li><p>Activity <b></b> {@link 427 android.app.Activity#onStart onStart()} {@link 428 android.app.Activity#onStop onStop()} Activity 429 Activity Activity 430 {@link android.app.Activity#onStop onStop()} Activity 431 432 {@link 433 android.app.Activity#onStart onStart()} {@link android.content.BroadcastReceiver} UI 434 {@link android.app.Activity#onStop onStop()} 435 Activity Activity {@link android.app.Activity#onStart onStart()} {@link 436 android.app.Activity#onStop onStop()} 437 </p></li> 438 439 <li><p>Activity <b></b> {@link 440 android.app.Activity#onResume onResume()} {@link android.app.Activity#onPause 441 onPause()} Activity Activity 442 Activity — {@link android.app.Activity#onPause onPause()} 443 444 445 </p></li> 446 </ul> 447 448 <p> 1 Activity Activity 449 450 <p> 451 452 <img src="{@docRoot}images/activity_lifecycle.png" alt="" /> 453 <p class="img-caption"><strong> 1. </strong>Activity </p> 454 455 <p> 1 Activity Activity 456 457 458 </p> 459 460 <p class="table-caption"><strong> 1. </strong>Activity 461 </p> 462 463 <table border="2" width="85%" frame="hsides" rules="rows"> 464 <colgroup align="left" span="3"></colgroup> 465 <colgroup align="left"></colgroup> 466 <colgroup align="center"></colgroup> 467 <colgroup align="center"></colgroup> 468 469 <thead> 470 <tr><th colspan="3"></th> <th></th> <th></th> <th></th></tr> 471 </thead> 472 473 <tbody> 474 <tr> 475 <td colspan="3" align="left"><code>{@link android.app.Activity#onCreate onCreate()}</code></td> 476 <td> Activity 477 — 478 Bundle Activity <a href="#actstate"> Activity </a> 479 480 481 482 <p> {@code onStart()}</p></td> 483 <td align="center"></td> 484 <td align="center">{@code onStart()}</td> 485 </tr> 486 487 <tr> 488 <td rowspan="5" style="border-left: none; border-right: none;"> </td> 489 <td colspan="2" align="left"><code>{@link android.app.Activity#onRestart 490 onRestart()}</code></td> 491 <td> Activity 492 493 <p> {@code onStart()}</p></td> 494 <td align="center"></td> 495 <td align="center">{@code onStart()}</td> 496 </tr> 497 498 <tr> 499 <td colspan="2" align="left"><code>{@link android.app.Activity#onStart onStart()}</code></td> 500 <td> Activity 501 <p> Activity {@code onResume()} Activity {@code onStop()} 502 </p></td> 503 <td align="center"></td> 504 <td align="center">{@code onResume()} <br/><br/> {@code onStop()}</td> 505 </tr> 506 507 <tr> 508 <td rowspan="2" style="border-left: none;"> </td> 509 <td align="left"><code>{@link android.app.Activity#onResume onResume()}</code></td> 510 <td> Activity 511 Activity Activity 512 513 <p> {@code onPause()}</p></td> 514 <td align="center"></td> 515 <td align="center">{@code onPause()}</td> 516 </tr> 517 518 <tr> 519 <td align="left"><code>{@link android.app.Activity#onPause onPause()}</code></td> 520 <td> Activity 521 CPU 522 523 Activity 524 525 <p> Activity {@code onResume()} Activity {@code onStop()} 526 527 </td> 528 <td align="center"><strong style="color:#800000"></strong></td> 529 <td align="center">{@code onResume()} <br/><br/> {@code onStop()}</td> 530 </tr> 531 532 <tr> 533 <td colspan="2" align="left"><code>{@link android.app.Activity#onStop onStop()}</code></td> 534 <td>Activity Activity Activity Activity Activity 535 536 537 <p> Activity {@code onRestart()} Activity 538 {@code onDestroy()} 539 </p></td> 540 <td align="center"><strong style="color:#800000"></strong></td> 541 <td align="center">{@code onRestart()} <br/><br/> {@code onDestroy()}</td> 542 </tr> 543 544 <tr> 545 <td colspan="3" align="left"><code>{@link android.app.Activity#onDestroy 546 onDestroy()}</code></td> 547 <td> Activity Activity 548 Activity Activity <code>{@link android.app.Activity#finish 549 finish()}</code> Activity 550 551 552 <code>{@link 553 android.app.Activity#isFinishing isFinishing()}</code> </td> 554 <td align="center"><strong style="color:#800000"></strong></td> 555 <td align="center"><em></em></td> 556 </tr> 557 </tbody> 558 </table> 559 560 <p> Activity <em></em> Activity 561 562 ({@link 563 android.app.Activity#onPause 564 onPause()}{@link android.app.Activity#onStop onStop()} {@link android.app.Activity#onDestroy 565 onDestroy()}) {@link android.app.Activity#onPause onPause()} 566 Activity {@link android.app.Activity#onPause onPause()} 567 <em></em>— 568 {@link 569 android.app.Activity#onStop onStop()} 570 {@link android.app.Activity#onDestroy onDestroy()} {@link android.app.Activity#onPause onPause()} 571 572 {@link android.app.Activity#onPause onPause()} 573 Activity 574 </p> 575 576 <p> <b></b> Activity 577 {@link android.app.Activity#onPause onPause()} 578 {@link android.app.Activity#onResume onResume()} 579 Activity {@link android.app.Activity#onPause onPause()} 580 Activity </p> 581 582 <p class="note"><strong></strong> 583 1 584 Activity —<a href="{@docRoot}guide/components/processes-and-threads.html"></a> Activity 585 586 </p> 587 588 589 <h3 id="SavingActivityState"> Activity </h3> 590 591 <p><a href="#Lifecycle"> Activity </a> Activity Activity 592 593 Activity {@link android.app.Activity} 594 — Activity 595 Activity Activity 596 597 </p> 598 599 <p> Activity {@link 600 android.app.Activity} 601 Activity Activity {@link android.app.Activity} 602 Activity Activity 603 604 Activity Activity {@link 605 android.app.Activity#onSaveInstanceState onSaveInstanceState()} 606 607 </p> 608 609 <p> 610 {@link android.app.Activity#onSaveInstanceState onSaveInstanceState()} Activity 611 {@link android.os.Bundle} 612 {@link 613 android.os.Bundle#putString putString()} {@link 614 android.os.Bundle#putInt putInt()} - Activity Activity Activity 615 {@link android.os.Bundle} 616 {@link android.app.Activity#onCreate onCreate()} {@link 617 android.app.Activity#onRestoreInstanceState onRestoreInstanceState()} 618 {@link android.os.Bundle} 619 Activity {@link 620 android.os.Bundle} 621 Activity</p> 622 623 <img src="{@docRoot}images/fundamentals/restore_instance.png" alt="" /> 624 <p class="img-caption"><strong> 2. </strong>Activity Activity ActivityActivity Activity Activity Activity 625 626 627 </p> 628 629 <p class="note"><strong></strong> Activity {@link 630 android.app.Activity#onSaveInstanceState onSaveInstanceState()} 631 <em></em> 632 Activity Activity 633 634 {@link android.app.Activity#onSaveInstanceState 635 onSaveInstanceState()} {@link 636 android.app.Activity#onStop onStop()} {@link android.app.Activity#onPause 637 onPause()} </p> 638 639 <p> {@link 640 android.app.Activity#onSaveInstanceState onSaveInstanceState()}{@link android.app.Activity} 641 {@link 642 android.app.Activity#onSaveInstanceState onSaveInstanceState()} Activity 643 {@link 644 android.view.View} {@link 645 android.view.View#onSaveInstanceState onSaveInstanceState()} 646 Android 647 Activity UI 648 {@link android.widget.EditText} 649 {@link android.widget.CheckBox} 650 ID <a href="{@docRoot}guide/topics/resources/layout-resource.html#idvalue">{@code android:id}</a> 651 ID 652 </p> 653 654 <div class="sidebox-wrapper"> 655 <div class="sidebox"> 656 <p> 657 {@link android.R.attr#saveEnabled android:saveEnabled} {@code "false"} {@link android.view.View#setSaveEnabled setSaveEnabled()} 658 Activity UI 659 </p> 660 </div> 661 </div> 662 663 <p> {@link 664 android.app.Activity#onSaveInstanceState onSaveInstanceState()} 665 Activity UI 666 Activity 667 UI UI 668 </p> 669 670 <p> {@link 671 android.app.Activity#onSaveInstanceState onSaveInstanceState()} UI 672 673 {@link android.app.Activity#onSaveInstanceState onSaveInstanceState()} 674 {@link 675 android.app.Activity#onRestoreInstanceState onRestoreInstanceState()} 676 </p> 677 678 <p class="note"><strong></strong> 679 {@link android.app.Activity#onSaveInstanceState 680 onSaveInstanceState()} Activity UI 681 — {@link 682 android.app.Activity#onPause onPause()} 683 Activity </p> 684 685 <p> 686 Activity 687 688 Activity 689 690 </p> 691 692 693 <h3 id="ConfigurationChanges"></h3> 694 695 <p> 696 Android Activity 697 {@link android.app.Activity#onDestroy} {@link 698 android.app.Activity#onCreate onCreate()} 699 700 701 </p> 702 703 <p> Activity Activity Activity 704 705 </p> 706 707 <p> 708 {@link 709 android.app.Activity#onSaveInstanceState onSaveInstanceState()} {@link 710 android.app.Activity#onRestoreInstanceState onRestoreInstanceState()} {@link 711 android.app.Activity#onCreate onCreate()} Activity </p> 712 713 <p><a href="{@docRoot}guide/topics/resources/runtime-changes.html"></a> 714 715 </p> 716 717 718 719 <h3 id="CoordinatingActivities"> Activity</h3> 720 721 <p> Activity Activity Activity Activity 722 723 Activity Activity Activity Activity Activity 724 725 726 </p> 727 728 <p> Activity Activity Activity 729 Activity A 730 Activity B </p> 731 732 <ol> 733 <li>Activity A {@link android.app.Activity#onPause onPause()} </li> 734 735 <li>Activity B {@link android.app.Activity#onCreate onCreate()}{@link 736 android.app.Activity#onStart onStart()} {@link android.app.Activity#onResume onResume()} 737 Activity B </li> 738 739 <li> Activity A {@link 740 android.app.Activity#onStop onStop()} </li> 741 </ol> 742 743 <p> Activity Activity 744 Activity Activity 745 {@link android.app.Activity#onPause onPause()} 746 {@link 747 android.app.Activity#onStop onStop()} </p> 748 749 <!-- 750 <h2>Beginner's Path</h2> 751 752 <p>For more information about how Android maintains a history of activities and 753 enables user multitasking, continue with the <b><a 754 href="{@docRoot}guide/components/tasks-and-back-stack.html">Tasks and Back 755 Stack</a></b> document.</p> 756 --> 757
