viewport_test.dart 41.5 KB
Newer Older
Ian Hickson's avatar
Ian Hickson committed
1
// Copyright 2014 The Flutter Authors. All rights reserved.
2 3 4
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

5 6 7 8 9
// This file is separate from viewport_caching_test.dart because we can't use
// both testWidgets and rendering_tester in the same file - testWidgets will
// initialize a binding, which rendering_tester will attempt to re-initialize
// (or vice versa).

10 11 12
import 'dart:ui';

import 'package:flutter_test/flutter_test.dart';
13
import 'package:flutter/foundation.dart';
14 15 16 17 18 19 20
import 'package:flutter/rendering.dart';
import 'package:flutter/widgets.dart';

void main() {
  testWidgets('Viewport getOffsetToReveal - down', (WidgetTester tester) async {
    List<Widget> children;
    await tester.pumpWidget(
21
      Directionality(
22
        textDirection: TextDirection.ltr,
23
        child: Center(
24 25 26
          child: Container(
            height: 200.0,
            width: 300.0,
27 28 29 30
            child: ListView(
              controller: ScrollController(initialScrollOffset: 300.0),
              children: children = List<Widget>.generate(20, (int i) {
                return Container(
31 32
                  height: 100.0,
                  width: 300.0,
33
                  child: Text('Tile $i'),
34 35 36 37 38 39 40 41
                );
              }),
            ),
          ),
        ),
      ),
    );

42
    final RenderAbstractViewport viewport = tester.allRenderObjects.whereType<RenderAbstractViewport>().first;
43 44 45 46

    final RenderObject target = tester.renderObject(find.byWidget(children[5], skipOffstage: false));
    RevealedOffset revealed = viewport.getOffsetToReveal(target, 0.0);
    expect(revealed.offset, 500.0);
Dan Field's avatar
Dan Field committed
47
    expect(revealed.rect, const Rect.fromLTWH(0.0, 0.0, 300.0, 100.0));
48 49 50

    revealed = viewport.getOffsetToReveal(target, 1.0);
    expect(revealed.offset, 400.0);
Dan Field's avatar
Dan Field committed
51
    expect(revealed.rect, const Rect.fromLTWH(0.0, 100.0, 300.0, 100.0));
52

Dan Field's avatar
Dan Field committed
53
    revealed = viewport.getOffsetToReveal(target, 0.0, rect: const Rect.fromLTWH(40.0, 40.0, 10.0, 10.0));
54
    expect(revealed.offset, 540.0);
Dan Field's avatar
Dan Field committed
55
    expect(revealed.rect, const Rect.fromLTWH(40.0, 0.0, 10.0, 10.0));
56

Dan Field's avatar
Dan Field committed
57
    revealed = viewport.getOffsetToReveal(target, 1.0, rect: const Rect.fromLTWH(40.0, 40.0, 10.0, 10.0));
58
    expect(revealed.offset, 350.0);
Dan Field's avatar
Dan Field committed
59
    expect(revealed.rect, const Rect.fromLTWH(40.0, 190.0, 10.0, 10.0));
60 61 62 63 64 65
  });

  testWidgets('Viewport getOffsetToReveal - right', (WidgetTester tester) async {
    List<Widget> children;

    await tester.pumpWidget(
66
      Directionality(
67
        textDirection: TextDirection.ltr,
68
        child: Center(
69 70 71
          child: Container(
            height: 300.0,
            width: 200.0,
72
            child: ListView(
73
              scrollDirection: Axis.horizontal,
74 75 76
              controller: ScrollController(initialScrollOffset: 300.0),
              children: children = List<Widget>.generate(20, (int i) {
                return Container(
77 78
                  height: 300.0,
                  width: 100.0,
79
                  child: Text('Tile $i'),
80 81 82 83 84 85 86 87
                );
              }),
            ),
          ),
        ),
      ),
    );

88
    final RenderAbstractViewport viewport = tester.allRenderObjects.whereType<RenderAbstractViewport>().first;
89 90 91 92

    final RenderObject target = tester.renderObject(find.byWidget(children[5], skipOffstage: false));
    RevealedOffset revealed = viewport.getOffsetToReveal(target, 0.0);
    expect(revealed.offset, 500.0);
Dan Field's avatar
Dan Field committed
93
    expect(revealed.rect, const Rect.fromLTWH(0.0, 0.0, 100.0, 300.0));
94 95 96

    revealed = viewport.getOffsetToReveal(target, 1.0);
    expect(revealed.offset, 400.0);
Dan Field's avatar
Dan Field committed
97
    expect(revealed.rect, const Rect.fromLTWH(100.0, 0.0, 100.0, 300.0));
98

Dan Field's avatar
Dan Field committed
99
    revealed = viewport.getOffsetToReveal(target, 0.0, rect: const Rect.fromLTWH(40.0, 40.0, 10.0, 10.0));
100
    expect(revealed.offset, 540.0);
Dan Field's avatar
Dan Field committed
101
    expect(revealed.rect, const Rect.fromLTWH(0.0, 40.0, 10.0, 10.0));
102

Dan Field's avatar
Dan Field committed
103
    revealed = viewport.getOffsetToReveal(target, 1.0, rect: const Rect.fromLTWH(40.0, 40.0, 10.0, 10.0));
104
    expect(revealed.offset, 350.0);
Dan Field's avatar
Dan Field committed
105
    expect(revealed.rect, const Rect.fromLTWH(190.0, 40.0, 10.0, 10.0));
106 107 108 109 110 111
  });

  testWidgets('Viewport getOffsetToReveal - up', (WidgetTester tester) async {
    List<Widget> children;

    await tester.pumpWidget(
112
      Directionality(
113
        textDirection: TextDirection.ltr,
114
        child: Center(
115 116 117
          child: Container(
            height: 200.0,
            width: 300.0,
118 119
            child: ListView(
              controller: ScrollController(initialScrollOffset: 300.0),
120
              reverse: true,
121 122
              children: children = List<Widget>.generate(20, (int i) {
                return Container(
123 124
                  height: 100.0,
                  width: 300.0,
125
                  child: Text('Tile $i'),
126 127 128 129 130 131 132 133
                );
              }),
            ),
          ),
        ),
      ),
    );

134
    final RenderAbstractViewport viewport = tester.allRenderObjects.whereType<RenderAbstractViewport>().first;
135 136 137 138

    final RenderObject target = tester.renderObject(find.byWidget(children[5], skipOffstage: false));
    RevealedOffset revealed = viewport.getOffsetToReveal(target, 0.0);
    expect(revealed.offset, 500.0);
Dan Field's avatar
Dan Field committed
139
    expect(revealed.rect, const Rect.fromLTWH(0.0, 100.0, 300.0, 100.0));
140 141 142

    revealed = viewport.getOffsetToReveal(target, 1.0);
    expect(revealed.offset, 400.0);
Dan Field's avatar
Dan Field committed
143
    expect(revealed.rect, const Rect.fromLTWH(0.0, 0.0, 300.0, 100.0));
144

Dan Field's avatar
Dan Field committed
145
    revealed = viewport.getOffsetToReveal(target, 0.0, rect: const Rect.fromLTWH(40.0, 40.0, 10.0, 10.0));
146
    expect(revealed.offset, 550.0);
Dan Field's avatar
Dan Field committed
147
    expect(revealed.rect, const Rect.fromLTWH(40.0, 190.0, 10.0, 10.0));
148

Dan Field's avatar
Dan Field committed
149
    revealed = viewport.getOffsetToReveal(target, 1.0, rect: const Rect.fromLTWH(40.0, 40.0, 10.0, 10.0));
150
    expect(revealed.offset, 360.0);
Dan Field's avatar
Dan Field committed
151
    expect(revealed.rect, const Rect.fromLTWH(40.0, 0.0, 10.0, 10.0));
152 153 154 155 156 157
  });

  testWidgets('Viewport getOffsetToReveal - left', (WidgetTester tester) async {
    List<Widget> children;

    await tester.pumpWidget(
158
      Directionality(
159
        textDirection: TextDirection.ltr,
160
        child: Center(
161 162 163
          child: Container(
            height: 300.0,
            width: 200.0,
164
            child: ListView(
165 166
              scrollDirection: Axis.horizontal,
              reverse: true,
167 168 169
              controller: ScrollController(initialScrollOffset: 300.0),
              children: children = List<Widget>.generate(20, (int i) {
                return Container(
170 171
                  height: 300.0,
                  width: 100.0,
172
                  child: Text('Tile $i'),
173 174 175 176 177 178 179 180
                );
              }),
            ),
          ),
        ),
      ),
    );

181
    final RenderAbstractViewport viewport = tester.allRenderObjects.whereType<RenderAbstractViewport>().first;
182 183 184 185

    final RenderObject target = tester.renderObject(find.byWidget(children[5], skipOffstage: false));
    RevealedOffset revealed = viewport.getOffsetToReveal(target, 0.0);
    expect(revealed.offset, 500.0);
Dan Field's avatar
Dan Field committed
186
    expect(revealed.rect, const Rect.fromLTWH(100.0, 0.0, 100.0, 300.0));
187 188 189

    revealed = viewport.getOffsetToReveal(target, 1.0);
    expect(revealed.offset, 400.0);
Dan Field's avatar
Dan Field committed
190
    expect(revealed.rect, const Rect.fromLTWH(0.0, 0.0, 100.0, 300.0));
191

Dan Field's avatar
Dan Field committed
192
    revealed = viewport.getOffsetToReveal(target, 0.0, rect: const Rect.fromLTWH(40.0, 40.0, 10.0, 10.0));
193
    expect(revealed.offset, 550.0);
Dan Field's avatar
Dan Field committed
194
    expect(revealed.rect, const Rect.fromLTWH(190.0, 40.0, 10.0, 10.0));
195

Dan Field's avatar
Dan Field committed
196
    revealed = viewport.getOffsetToReveal(target, 1.0, rect: const Rect.fromLTWH(40.0, 40.0, 10.0, 10.0));
197
    expect(revealed.offset, 360.0);
Dan Field's avatar
Dan Field committed
198
    expect(revealed.rect, const Rect.fromLTWH(0.0, 40.0, 10.0, 10.0));
199
  }, skip: isBrowser);
200

201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216
  testWidgets('Viewport getOffsetToReveal Sliver - down', (WidgetTester tester) async {
    final List<Widget> children = <Widget>[];
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Center(
          child: Container(
            height: 200.0,
            width: 300.0,
            child: CustomScrollView(
              controller: ScrollController(initialScrollOffset: 300.0),
              slivers: List<Widget>.generate(20, (int i) {
                final Widget sliver = SliverToBoxAdapter(
                  child: Container(
                    height: 100.0,
                    child: Text('Tile $i'),
217
                  ),
218 219 220 221 222 223 224 225 226 227 228 229 230
                );
                children.add(sliver);
                return SliverPadding(
                  padding: const EdgeInsets.all(22.0),
                  sliver: sliver,
                );
              }),
            ),
          ),
        ),
      ),
    );

231
    final RenderAbstractViewport viewport = tester.allRenderObjects.whereType<RenderAbstractViewport>().first;
232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257

    final RenderObject target = tester.renderObject(find.byWidget(children[5], skipOffstage: false));
    RevealedOffset revealed = viewport.getOffsetToReveal(target, 0.0);
    expect(revealed.offset, 5 * (100 + 22 + 22) + 22);

    revealed = viewport.getOffsetToReveal(target, 1.0);
    expect(revealed.offset, 5 * (100 + 22 + 22) + 22 - 100);
  });

  testWidgets('Viewport getOffsetToReveal Sliver - right', (WidgetTester tester) async {
    final List<Widget> children = <Widget>[];
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Center(
          child: Container(
            height: 300.0,
            width: 200.0,
            child: CustomScrollView(
              scrollDirection: Axis.horizontal,
              controller: ScrollController(initialScrollOffset: 300.0),
              slivers: List<Widget>.generate(20, (int i) {
                final Widget sliver = SliverToBoxAdapter(
                    child: Container(
                      width: 100.0,
                      child: Text('Tile $i'),
258
                    ),
259 260 261 262 263 264 265 266 267 268 269 270 271
                );
                children.add(sliver);
                return SliverPadding(
                  padding: const EdgeInsets.all(22.0),
                  sliver: sliver,
                );
              }),
            ),
          ),
        ),
      ),
    );

272
    final RenderAbstractViewport viewport = tester.allRenderObjects.whereType<RenderAbstractViewport>().first;
273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298

    final RenderObject target = tester.renderObject(find.byWidget(children[5], skipOffstage: false));
    RevealedOffset revealed = viewport.getOffsetToReveal(target, 0.0);
    expect(revealed.offset, 5 * (100 + 22 + 22) + 22);

    revealed = viewport.getOffsetToReveal(target, 1.0);
    expect(revealed.offset, 5 * (100 + 22 + 22) + 22 - 100);
  });

  testWidgets('Viewport getOffsetToReveal Sliver - up', (WidgetTester tester) async {
    final List<Widget> children = <Widget>[];
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Center(
          child: Container(
            height: 200.0,
            width: 300.0,
            child: CustomScrollView(
              controller: ScrollController(initialScrollOffset: 300.0),
              reverse: true,
              slivers: List<Widget>.generate(20, (int i) {
                final Widget sliver = SliverToBoxAdapter(
                    child: Container(
                      height: 100.0,
                      child: Text('Tile $i'),
299
                    ),
300 301 302 303 304 305 306 307 308 309 310 311 312
                );
                children.add(sliver);
                return SliverPadding(
                  padding: const EdgeInsets.all(22.0),
                  sliver: sliver,
                );
              }),
            ),
          ),
        ),
      ),
    );

313
    final RenderAbstractViewport viewport = tester.allRenderObjects.whereType<RenderAbstractViewport>().first;
314 315 316 317 318 319 320 321 322

    final RenderObject target = tester.renderObject(find.byWidget(children[5], skipOffstage: false));
    RevealedOffset revealed = viewport.getOffsetToReveal(target, 0.0);
    expect(revealed.offset, 5 * (100 + 22 + 22) + 22);

    revealed = viewport.getOffsetToReveal(target, 1.0);
    expect(revealed.offset, 5 * (100 + 22 + 22) + 22 - 100);
  });

323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362
  testWidgets('Viewport getOffsetToReveal Sliver - up - reverse growth', (WidgetTester tester) async {
    const Key centerKey = ValueKey<String>('center');
    final Widget centerSliver = SliverPadding(
      key: centerKey,
      padding: const EdgeInsets.all(22.0),
      sliver: SliverToBoxAdapter(
        child: Container(
          height: 100.0,
          child: const Text('Tile center'),
        ),
      ),
    );
    final Widget lowerItem = Container(
      height: 100.0,
      child: const Text('Tile lower'),
    );
    final Widget lowerSliver = SliverPadding(
      padding: const EdgeInsets.all(22.0),
      sliver: SliverToBoxAdapter(
        child: lowerItem,
      ),
    );

    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Center(
          child: Container(
            height: 200.0,
            width: 300.0,
            child: CustomScrollView(
              center: centerKey,
              reverse: true,
              slivers: <Widget>[lowerSliver, centerSliver],
            ),
          ),
        ),
      ),
    );

363
    final RenderAbstractViewport viewport = tester.allRenderObjects.whereType<RenderAbstractViewport>().first;
364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413

    final RenderObject target = tester.renderObject(find.byWidget(lowerItem, skipOffstage: false));
    RevealedOffset revealed = viewport.getOffsetToReveal(target, 0.0);
    expect(revealed.offset, - 100 - 22);

    revealed = viewport.getOffsetToReveal(target, 1.0);
    expect(revealed.offset, - 100 - 22 - 100);
  });

  testWidgets('Viewport getOffsetToReveal Sliver - left - reverse growth', (WidgetTester tester) async {
    const Key centerKey = ValueKey<String>('center');
    final Widget centerSliver = SliverPadding(
      key: centerKey,
      padding: const EdgeInsets.all(22.0),
      sliver: SliverToBoxAdapter(
        child: Container(
          width: 100.0,
          child: const Text('Tile center'),
        ),
      ),
    );
    final Widget lowerItem = Container(
      width: 100.0,
      child: const Text('Tile lower'),
    );
    final Widget lowerSliver = SliverPadding(
      padding: const EdgeInsets.all(22.0),
      sliver: SliverToBoxAdapter(
        child: lowerItem,
      ),
    );

    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Center(
          child: Container(
            height: 200.0,
            width: 300.0,
            child: CustomScrollView(
              scrollDirection: Axis.horizontal,
              center: centerKey,
              reverse: true,
              slivers: <Widget>[lowerSliver, centerSliver],
            ),
          ),
        ),
      ),
    );

414
    final RenderAbstractViewport viewport = tester.allRenderObjects.whereType<RenderAbstractViewport>().first;
415 416 417 418 419 420 421 422 423

    final RenderObject target = tester.renderObject(find.byWidget(lowerItem, skipOffstage: false));
    RevealedOffset revealed = viewport.getOffsetToReveal(target, 0.0);
    expect(revealed.offset, -100 - 22);

    revealed = viewport.getOffsetToReveal(target, 1.0);
    expect(revealed.offset, - 100 - 22 - 200);
  });

424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441
  testWidgets('Viewport getOffsetToReveal Sliver - left', (WidgetTester tester) async {
    final List<Widget> children = <Widget>[];
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Center(
          child: Container(
            height: 300.0,
            width: 200.0,
            child: CustomScrollView(
              scrollDirection: Axis.horizontal,
              reverse: true,
              controller: ScrollController(initialScrollOffset: 300.0),
              slivers: List<Widget>.generate(20, (int i) {
                final Widget sliver = SliverToBoxAdapter(
                    child: Container(
                      width: 100.0,
                      child: Text('Tile $i'),
442
                    ),
443 444 445 446 447 448 449 450 451 452 453 454 455
                );
                children.add(sliver);
                return SliverPadding(
                  padding: const EdgeInsets.all(22.0),
                  sliver: sliver,
                );
              }),
            ),
          ),
        ),
      ),
    );

456
    final RenderAbstractViewport viewport = tester.allRenderObjects.whereType<RenderAbstractViewport>().first;
457 458 459 460 461 462 463 464 465

    final RenderObject target = tester.renderObject(find.byWidget(children[5], skipOffstage: false));
    RevealedOffset revealed = viewport.getOffsetToReveal(target, 0.0);
    expect(revealed.offset, 5 * (100 + 22 + 22) + 22);

    revealed = viewport.getOffsetToReveal(target, 1.0);
    expect(revealed.offset, 5 * (100 + 22 + 22) + 22 - 100);
  });

466
  testWidgets('Nested Viewports showOnScreen', (WidgetTester tester) async {
467 468 469
    final List<List<Widget>> children = List<List<Widget>>(10);
    final List<ScrollController> controllersX = List<ScrollController>.generate(10, (int i) => ScrollController(initialScrollOffset: 400.0));
    final ScrollController controllerY  = ScrollController(initialScrollOffset: 400.0);
470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489

    /// Builds a gird:
    ///
    ///       <- x ->
    ///   0 1 2 3 4 5 6 7 8 9
    /// 0 c c c c c c c c c c
    /// 1 c c c c c c c c c c
    /// 2 c c c c c c c c c c
    /// 3 c c c c c c c c c c  y
    /// 4 c c c c v v c c c c
    /// 5 c c c c v v c c c c
    /// 6 c c c c c c c c c c
    /// 7 c c c c c c c c c c
    /// 8 c c c c c c c c c c
    /// 9 c c c c c c c c c c
    ///
    /// Each c is a 100x100 container, v are containers visible in initial
    /// viewport.

    await tester.pumpWidget(
490
      Directionality(
491
        textDirection: TextDirection.ltr,
492
        child: Center(
493 494 495
          child: Container(
            height: 200.0,
            width: 200.0,
496
            child: ListView(
497
              controller: controllerY,
498
              children: List<Widget>.generate(10, (int y) {
499 500
                return Container(
                  height: 100.0,
501
                  child: ListView(
502 503
                    scrollDirection: Axis.horizontal,
                    controller: controllersX[y],
504 505
                    children: children[y] = List<Widget>.generate(10, (int x) {
                      return Container(
506 507
                        height: 100.0,
                        width: 100.0,
508
                        child: Text('$x,$y'),
509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626
                      );
                    }),
                  ),
                );
              }),
            ),
          ),
        ),
      ),
    );

    // Already in viewport
    tester.renderObject(find.byWidget(children[4][4], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllersX[4].offset, 400.0);
    expect(controllerY.offset, 400.0);

    controllersX[4].jumpTo(400.0);
    controllerY.jumpTo(400.0);
    await tester.pumpAndSettle();

    // Above viewport
    tester.renderObject(find.byWidget(children[3][4], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllersX[3].offset, 400.0);
    expect(controllerY.offset, 300.0);

    controllersX[3].jumpTo(400.0);
    controllerY.jumpTo(400.0);
    await tester.pumpAndSettle();

    // Below viewport
    tester.renderObject(find.byWidget(children[6][4], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllersX[6].offset, 400.0);
    expect(controllerY.offset, 500.0);

    controllersX[6].jumpTo(400.0);
    controllerY.jumpTo(400.0);
    await tester.pumpAndSettle();

    // Left of viewport
    tester.renderObject(find.byWidget(children[4][3], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllersX[4].offset, 300.0);
    expect(controllerY.offset, 400.0);

    controllersX[4].jumpTo(400.0);
    controllerY.jumpTo(400.0);
    await tester.pumpAndSettle();

    // Right of viewport
    tester.renderObject(find.byWidget(children[4][6], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllersX[4].offset, 500.0);
    expect(controllerY.offset, 400.0);

    controllersX[4].jumpTo(400.0);
    controllerY.jumpTo(400.0);
    await tester.pumpAndSettle();

    // Above and left of viewport
    tester.renderObject(find.byWidget(children[3][3], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllersX[3].offset, 300.0);
    expect(controllerY.offset, 300.0);

    controllersX[3].jumpTo(400.0);
    controllerY.jumpTo(400.0);
    await tester.pumpAndSettle();

    // Below and left of viewport
    tester.renderObject(find.byWidget(children[6][3], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllersX[6].offset, 300.0);
    expect(controllerY.offset, 500.0);

    controllersX[6].jumpTo(400.0);
    controllerY.jumpTo(400.0);
    await tester.pumpAndSettle();

    // Above and right of viewport
    tester.renderObject(find.byWidget(children[3][6], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllersX[3].offset, 500.0);
    expect(controllerY.offset, 300.0);

    controllersX[3].jumpTo(400.0);
    controllerY.jumpTo(400.0);
    await tester.pumpAndSettle();

    // Below and right of viewport
    tester.renderObject(find.byWidget(children[6][6], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllersX[6].offset, 500.0);
    expect(controllerY.offset, 500.0);

    controllersX[6].jumpTo(400.0);
    controllerY.jumpTo(400.0);
    await tester.pumpAndSettle();

    // Below and right of viewport with animations
    tester.renderObject(find.byWidget(children[6][6], skipOffstage: false)).showOnScreen(duration: const Duration(seconds: 2));
    await tester.pump();
    await tester.pump(const Duration(seconds: 1));
    expect(tester.hasRunningAnimations, isTrue);
    expect(controllersX[6].offset, greaterThan(400.0));
    expect(controllersX[6].offset, lessThan(500.0));
    expect(controllerY.offset, greaterThan(400.0));
    expect(controllerY.offset, lessThan(500.0));
    await tester.pumpAndSettle();
    expect(controllersX[6].offset, 500.0);
    expect(controllerY.offset, 500.0);
  });

  group('Nested viewports (same orientation) showOnScreen', () {
    List<Widget> children;

627
    Future<void> buildNestedScroller({ WidgetTester tester, ScrollController inner, ScrollController outer }) {
628
      return tester.pumpWidget(
629
        Directionality(
630
          textDirection: TextDirection.ltr,
631
          child: Center(
632 633 634
            child: Container(
              height: 200.0,
              width: 300.0,
635
              child: ListView(
636 637
                controller: outer,
                children: <Widget>[
638
                  Container(
639 640
                    height: 200.0,
                  ),
641
                  Container(
642 643
                    height: 200.0,
                    width: 300.0,
644
                    child: ListView(
645
                      controller: inner,
646 647
                      children: children = List<Widget>.generate(10, (int i) {
                        return Container(
648 649
                          height: 100.0,
                          width: 300.0,
650
                          child: Text('$i'),
651 652 653 654
                        );
                      }),
                    ),
                  ),
655
                  Container(
656
                    height: 200.0,
657
                  ),
658 659 660 661 662 663 664 665
                ],
              ),
            ),
          ),
        ),
      );
    }

666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730
    testWidgets('Reverse List showOnScreen', (WidgetTester tester) async {
      const double screenHeight = 400.0;
      const double screenWidth = 400.0;
      const double itemHeight = screenHeight / 10.0;
      const ValueKey<String> centerKey = ValueKey<String>('center');

      tester.binding.window.devicePixelRatioTestValue = 1.0;
      tester.binding.window.physicalSizeTestValue = const Size(screenWidth, screenHeight);

      await tester.pumpWidget(Directionality(
        textDirection: TextDirection.ltr,
        child: CustomScrollView(
            center: centerKey,
            reverse: true,
            slivers: <Widget>[
              SliverList(
                delegate: SliverChildListDelegate(
                  List<Widget>.generate(
                    10,
                        (int index) => SizedBox(
                      height: itemHeight,
                      child: Text('Item ${-index - 1}'),
                    ),
                  ),
                ),
              ),
              SliverList(
                key: centerKey,
                delegate: SliverChildListDelegate(
                  List<Widget>.generate(
                    1,
                        (int index) => const SizedBox(
                      height: itemHeight,
                      child: Text('Item 0'),
                    ),
                  ),
                ),
              ),
              SliverList(
                delegate: SliverChildListDelegate(
                  List<Widget>.generate(
                    10,
                    (int index) => SizedBox(
                      height: itemHeight,
                      child: Text('Item ${index + 1}'),
                    ),
                  ),
                ),
              ),
            ],
          ),
        ),
      );

      expect(find.text('Item -1'), findsNothing);

      final RenderBox itemNeg1 =
        tester.renderObject(find.text('Item -1', skipOffstage: false));

      itemNeg1.showOnScreen(duration: const Duration(seconds: 1));
      await tester.pumpAndSettle();

      expect(find.text('Item -1'), findsOneWidget);
    });

731
    testWidgets('in view in inner, but not in outer', (WidgetTester tester) async {
732 733
      final ScrollController inner = ScrollController();
      final ScrollController outer = ScrollController();
734 735 736 737 738 739 740 741 742 743 744 745 746 747 748
      await buildNestedScroller(
        tester: tester,
        inner: inner,
        outer: outer,
      );
      expect(outer.offset, 0.0);
      expect(inner.offset, 0.0);

      tester.renderObject(find.byWidget(children[0], skipOffstage: false)).showOnScreen();
      await tester.pumpAndSettle();
      expect(inner.offset, 0.0);
      expect(outer.offset, 100.0);
    });

    testWidgets('not in view of neither inner nor outer', (WidgetTester tester) async {
749 750
      final ScrollController inner = ScrollController();
      final ScrollController outer = ScrollController();
751 752 753 754 755 756 757 758 759 760 761 762 763 764 765
      await buildNestedScroller(
        tester: tester,
        inner: inner,
        outer: outer,
      );
      expect(outer.offset, 0.0);
      expect(inner.offset, 0.0);

      tester.renderObject(find.byWidget(children[4], skipOffstage: false)).showOnScreen();
      await tester.pumpAndSettle();
      expect(inner.offset, 300.0);
      expect(outer.offset, 200.0);
    });

    testWidgets('in view in inner and outer', (WidgetTester tester) async {
766 767
      final ScrollController inner = ScrollController(initialScrollOffset: 200.0);
      final ScrollController outer = ScrollController(initialScrollOffset: 200.0);
768 769 770 771 772 773 774 775 776 777 778 779 780 781 782
      await buildNestedScroller(
        tester: tester,
        inner: inner,
        outer: outer,
      );
      expect(outer.offset, 200.0);
      expect(inner.offset, 200.0);

      tester.renderObject(find.byWidget(children[2])).showOnScreen();
      await tester.pumpAndSettle();
      expect(outer.offset, 200.0);
      expect(inner.offset, 200.0);
    });

    testWidgets('inner shown in outer, but item not visible', (WidgetTester tester) async {
783 784
      final ScrollController inner = ScrollController(initialScrollOffset: 200.0);
      final ScrollController outer = ScrollController(initialScrollOffset: 200.0);
785 786 787 788 789 790 791 792 793 794 795 796 797 798 799
      await buildNestedScroller(
        tester: tester,
        inner: inner,
        outer: outer,
      );
      expect(outer.offset, 200.0);
      expect(inner.offset, 200.0);

      tester.renderObject(find.byWidget(children[5], skipOffstage: false)).showOnScreen();
      await tester.pumpAndSettle();
      expect(outer.offset, 200.0);
      expect(inner.offset, 400.0);
    });

    testWidgets('inner half shown in outer, item only visible in inner', (WidgetTester tester) async {
800 801
      final ScrollController inner = ScrollController();
      final ScrollController outer = ScrollController(initialScrollOffset: 100.0);
802 803 804 805 806 807 808 809 810 811 812 813 814 815 816
      await buildNestedScroller(
        tester: tester,
        inner: inner,
        outer: outer,
      );
      expect(outer.offset, 100.0);
      expect(inner.offset, 0.0);

      tester.renderObject(find.byWidget(children[1])).showOnScreen();
      await tester.pumpAndSettle();
      expect(outer.offset, 200.0);
      expect(inner.offset, 0.0);
    });
  });

817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928
  testWidgets('Nested Viewports showOnScreen with allowImplicitScrolling=false for inner viewport', (WidgetTester tester) async {
    // Regression test for https://github.com/flutter/flutter/issues/20893.

    List<Widget> slivers;
    final ScrollController controllerX =  ScrollController(initialScrollOffset: 0.0);
    final ScrollController controllerY  = ScrollController(initialScrollOffset: 0.0);

    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Center(
          child: Container(
            height: 200.0,
            width: 200.0,
            child: ListView(
              controller: controllerY,
              children: <Widget>[
                Container(
                  height: 150.0,
                ),
                Container(
                  height: 100.0,
                  child: ListView(
                    physics: const PageScrollPhysics(), // Turns off `allowImplicitScrolling`
                    scrollDirection: Axis.horizontal,
                    controller: controllerX,
                    children: slivers = <Widget>[
                      Container(
                        width: 150.0,
                      ),
                      Container(
                        width: 150.0,
                      ),
                    ],
                  ),
                ),
                Container(
                  height: 150.0,
                ),
              ],
            ),
          ),
        ),
      ),
    );

    tester.renderObject(find.byWidget(slivers[1])).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllerX.offset, 0.0);
    expect(controllerY.offset, 50.0);
  });

  testWidgets('Nested Viewports showOnScreen on Sliver with allowImplicitScrolling=false for inner viewport', (WidgetTester tester) async {
    Widget sliver;
    final ScrollController controllerX =  ScrollController(initialScrollOffset: 0.0);
    final ScrollController controllerY  = ScrollController(initialScrollOffset: 0.0);

    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Center(
          child: Container(
            height: 200.0,
            width: 200.0,
            child: ListView(
              controller: controllerY,
              children: <Widget>[
                Container(
                  height: 150.0,
                ),
                Container(
                  height: 100.0,
                  child: CustomScrollView(
                    physics: const PageScrollPhysics(), // Turns off `allowImplicitScrolling`
                    scrollDirection: Axis.horizontal,
                    controller: controllerX,
                    slivers: <Widget>[
                      SliverPadding(
                        padding: const EdgeInsets.all(25.0),
                        sliver: SliverToBoxAdapter(
                          child: Container(
                            width: 100.0,
                          ),
                        ),
                      ),
                      SliverPadding(
                        padding: const EdgeInsets.all(25.0),
                        sliver: sliver = SliverToBoxAdapter(
                          child: Container(
                            width: 100.0,
                          ),
                        ),
                      ),
                    ],
                  ),
                ),
                Container(
                  height: 150.0,
                ),
              ],
            ),
          ),
        ),
      ),
    );

    tester.renderObject(find.byWidget(sliver)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controllerX.offset, 0.0);
    expect(controllerY.offset, 25.0);
  });

929 930 931 932 933
  testWidgets('Viewport showOnScreen with objects larger than viewport', (WidgetTester tester) async {
    List<Widget> children;
    ScrollController controller;

    await tester.pumpWidget(
934
      Directionality(
935
        textDirection: TextDirection.ltr,
936
        child: Center(
937 938
          child: Container(
            height: 200.0,
939 940 941 942
            child: ListView(
              controller: controller = ScrollController(initialScrollOffset: 300.0),
              children: children = List<Widget>.generate(20, (int i) {
                return Container(
943
                  height: 300.0,
944
                  child: Text('Tile $i'),
945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987
                );
              }),
            ),
          ),
        ),
      ),
    );

    expect(controller.offset, 300.0);

    // Already aligned with leading edge, nothing happens.
    tester.renderObject(find.byWidget(children[1], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controller.offset, 300.0);

    // Above leading edge aligns trailing edges
    tester.renderObject(find.byWidget(children[0], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controller.offset, 100.0);

    // Below trailing edge aligns leading edges
    tester.renderObject(find.byWidget(children[1], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controller.offset, 300.0);

    controller.jumpTo(250.0);
    await tester.pumpAndSettle();
    expect(controller.offset, 250.0);

    // Partly visible across leading edge aligns trailing edges
    tester.renderObject(find.byWidget(children[0], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controller.offset, 100.0);

    controller.jumpTo(150.0);
    await tester.pumpAndSettle();
    expect(controller.offset, 150.0);

    // Partly visible across trailing edge aligns leading edges
    tester.renderObject(find.byWidget(children[1], skipOffstage: false)).showOnScreen();
    await tester.pumpAndSettle();
    expect(controller.offset, 300.0);
  });
988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049

  group('unbounded constraints control test', () {
    Widget buildNestedWidget([Axis a1 = Axis.vertical, Axis a2 = Axis.horizontal]) {
      return Directionality(
        textDirection: TextDirection.ltr,
        child: Center(
          child: Container(
            child: ListView(
              scrollDirection: a1,
              children: List<Widget>.generate(10, (int y) {
                return Container(
                  child: ListView(
                    scrollDirection: a2,
                  ),
                );
              }),
            ),
          ),
        ),
      );
    }

    Future<void> expectFlutterError({
      Widget widget,
      WidgetTester tester,
      String message,
    }) async {
      final List<FlutterErrorDetails> errors = <FlutterErrorDetails>[];
      final FlutterExceptionHandler oldHandler = FlutterError.onError;
      FlutterError.onError = (FlutterErrorDetails error) => errors.add(error);
      try {
        await tester.pumpWidget(widget);
      } finally {
        FlutterError.onError = oldHandler;
      }
      expect(errors, isNotEmpty);
      expect(errors.first.exception, isFlutterError);
      expect(errors.first.exception.toStringDeep(), message);
    }

    testWidgets('Horizontal viewport was given unbounded height', (WidgetTester tester) async {
      await expectFlutterError(
        widget: buildNestedWidget(),
        tester: tester,
        message:
          'FlutterError\n'
          '   Horizontal viewport was given unbounded height.\n'
          '   Viewports expand in the cross axis to fill their container and\n'
          '   constrain their children to match their extent in the cross axis.\n'
          '   In this case, a horizontal viewport was given an unlimited amount\n'
          '   of vertical space in which to expand.\n',
      );
    });

    testWidgets('Horizontal viewport was given unbounded width', (WidgetTester tester) async {
      await expectFlutterError(
        widget: buildNestedWidget(Axis.horizontal, Axis.horizontal),
        tester: tester,
        message:
          'FlutterError\n'
          '   Horizontal viewport was given unbounded width.\n'
          '   Viewports expand in the scrolling direction to fill their\n'
1050
          '   container. In this case, a horizontal viewport was given an\n'
1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146
          '   unlimited amount of horizontal space in which to expand. This\n'
          '   situation typically happens when a scrollable widget is nested\n'
          '   inside another scrollable widget.\n'
          '   If this widget is always nested in a scrollable widget there is\n'
          '   no need to use a viewport because there will always be enough\n'
          '   horizontal space for the children. In this case, consider using a\n'
          '   Row instead. Otherwise, consider using the "shrinkWrap" property\n'
          '   (or a ShrinkWrappingViewport) to size the width of the viewport\n'
          '   to the sum of the widths of its children.\n'
      );
    });

    testWidgets('Vertical viewport was given unbounded width', (WidgetTester tester) async {
      await expectFlutterError(
        widget: buildNestedWidget(Axis.horizontal, Axis.vertical),
        tester: tester,
        message:
          'FlutterError\n'
          '   Vertical viewport was given unbounded width.\n'
          '   Viewports expand in the cross axis to fill their container and\n'
          '   constrain their children to match their extent in the cross axis.\n'
          '   In this case, a vertical viewport was given an unlimited amount\n'
          '   of horizontal space in which to expand.\n'
      );
    });

    testWidgets('Vertical viewport was given unbounded height', (WidgetTester tester) async {
      await expectFlutterError(
        widget: buildNestedWidget(Axis.vertical, Axis.vertical),
        tester: tester,
        message:
          'FlutterError\n'
          '   Vertical viewport was given unbounded height.\n'
          '   Viewports expand in the scrolling direction to fill their\n'
          '   container. In this case, a vertical viewport was given an\n'
          '   unlimited amount of vertical space in which to expand. This\n'
          '   situation typically happens when a scrollable widget is nested\n'
          '   inside another scrollable widget.\n'
          '   If this widget is always nested in a scrollable widget there is\n'
          '   no need to use a viewport because there will always be enough\n'
          '   vertical space for the children. In this case, consider using a\n'
          '   Column instead. Otherwise, consider using the "shrinkWrap"\n'
          '   property (or a ShrinkWrappingViewport) to size the height of the\n'
          '   viewport to the sum of the heights of its children.\n'
      );
    });
  });

  test('Viewport debugThrowIfNotCheckingIntrinsics() control test', () {
    final RenderViewport renderViewport = RenderViewport(
      crossAxisDirection: AxisDirection.right, offset: ViewportOffset.zero()
    );
    FlutterError error;
    try {
      renderViewport.computeMinIntrinsicHeight(0);
    } on FlutterError catch (e) {
      error = e;
    }
    expect(error, isNotNull);
    expect(
      error.toStringDeep(),
      'FlutterError\n'
      '   RenderViewport does not support returning intrinsic dimensions.\n'
      '   Calculating the intrinsic dimensions would require instantiating\n'
      '   every child of the viewport, which defeats the point of viewports\n'
      '   being lazy.\n'
      '   If you are merely trying to shrink-wrap the viewport in the main\n'
      '   axis direction, consider a RenderShrinkWrappingViewport render\n'
      '   object (ShrinkWrappingViewport widget), which achieves that\n'
      '   effect without implementing the intrinsic dimension API.\n',
    );

    final RenderShrinkWrappingViewport renderShrinkWrappingViewport = RenderShrinkWrappingViewport(
      crossAxisDirection: AxisDirection.right, offset: ViewportOffset.zero()
    );
    error = null;
    try {
      renderShrinkWrappingViewport.computeMinIntrinsicHeight(0);
    } on FlutterError catch (e) {
      error = e;
    }
    expect(error, isNotNull);
    expect(
      error.toStringDeep(),
      'FlutterError\n'
      '   RenderShrinkWrappingViewport does not support returning intrinsic\n'
      '   dimensions.\n'
      '   Calculating the intrinsic dimensions would require instantiating\n'
      '   every child of the viewport, which defeats the point of viewports\n'
      '   being lazy.\n'
      '   If you are merely trying to shrink-wrap the viewport in the main\n'
      '   axis direction, you should be able to achieve that effect by just\n'
      '   giving the viewport loose constraints, without needing to measure\n'
      '   its intrinsic dimensions.\n',
    );
  });
1147

Dan Field's avatar
Dan Field committed
1148
  testWidgets('Handles infinite constraints when TargetPlatform is iOS or macOS', (WidgetTester tester) async {
1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177
    // regression test for https://github.com/flutter/flutter/issues/45866
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            GridView(
              shrinkWrap: true,
              gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
                  crossAxisCount: 3,
                  childAspectRatio: 3,
                  mainAxisSpacing: 3,
                  crossAxisSpacing: 3),
              children: const <Widget>[
                Text('a'),
                Text('b'),
                Text('c'),
              ],
            ),
          ],
        ),
      ),
    );

    expect(find.text('b'), findsOneWidget);
    await tester.drag(find.text('b'), const Offset(0, 200));
    await tester.pumpAndSettle();
Dan Field's avatar
Dan Field committed
1178
  }, variant: const TargetPlatformVariant(<TargetPlatform>{ TargetPlatform.iOS, TargetPlatform.macOS }));
1179
}