[webview_flutter] Fix iOS WebView ignoring SafeArea widget and iOS 13 WebView scroll indicator showing at random location.

packages/webview_flutter/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.3.19+4
+
+* On iOS, fix the scroll view content inset is automatically adjusted. After the fix, the content position of the WebView is customizable by Flutter.
+* Fix an iOS 13 bug where the scroll indicator shows at random location.
+
 ## 0.3.19+3
 
 * Setup XCTests.

packages/webview_flutter/ios/Classes/FlutterWebView.m

@@ -77,6 +77,13 @@ - (instancetype)initWithFrame:(CGRect)frame
       [weakSelf onMethodCall:call result:result];
     }];
 
+    if (@available(iOS 11.0, *)) {
+      _webView.scrollView.contentInsetAdjustmentBehavior = UIScrollViewContentInsetAdjustmentNever;
+      if (@available(iOS 13.0, *)) {
+        _webView.scrollView.automaticallyAdjustsScrollIndicatorInsets = NO;
+      }
+    }
+
     [self applySettings:settings];
     // TODO(amirh): return an error if apply settings failed once it's possible to do so.
     // https://github.com/flutter/flutter/issues/36228

packages/webview_flutter/ios/Tests/FLTWebViewTests.m

@@ -35,4 +35,33 @@ - (void)canInitFLTWebViewFactory {
   XCTAssertNotNil(factory);
 }
 
+- (void)webViewContentInsetBehaviorShouldBeNeverOnIOS11 {
+  if (@available(iOS 11, *)) {
+    FLTWebViewController *controller =
+        [[FLTWebViewController alloc] initWithFrame:CGRectMake(0, 0, 300, 400)
+                                     viewIdentifier:1
+                                          arguments:nil
+                                    binaryMessenger:self.mockBinaryMessenger];
+    UIView *view = controller.view;
+    XCTAssertTrue([view isKindOfClass:WKWebView.class]);
+    WKWebView *webView = (WKWebView *)view;
+    XCTAssertEqual(webView.scrollView.contentInsetAdjustmentBehavior,
+                   UIScrollViewContentInsetAdjustmentNever);
+  }
+}
+
+- (void)webViewScrollIndicatorAticautomaticallyAdjustsScrollIndicatorInsetsShouldbeNoOnIOS13 {
+  if (@available(iOS 13, *)) {
+    FLTWebViewController *controller =
+        [[FLTWebViewController alloc] initWithFrame:CGRectMake(0, 0, 300, 400)
+                                     viewIdentifier:1
+                                          arguments:nil
+                                    binaryMessenger:self.mockBinaryMessenger];
+    UIView *view = controller.view;
+    XCTAssertTrue([view isKindOfClass:WKWebView.class]);
+    WKWebView *webView = (WKWebView *)view;
+    XCTAssertFalse(webView.scrollView.automaticallyAdjustsScrollIndicatorInsets);
+  }
+}
+
 @end

packages/webview_flutter/pubspec.yaml

@@ -1,6 +1,6 @@
 name: webview_flutter
 description: A Flutter plugin that provides a WebView widget on Android and iOS.
-version: 0.3.19+3
+version: 0.3.19+4
 homepage: https://github.com/flutter/plugins/tree/master/packages/webview_flutter
 
 environment: