Fix image placeholder (#2564)

* [iOS] Make sure that placeholder do not override main image. * [iOS] Make sure that placeholder do not override main image.
apache · Jun 17, 2019 · 07151c3 · 07151c3
1 parent a31c982
commit 07151c3
Showing 1 changed file with 25 additions and 2 deletions.
diff --git a/ios/sdk/WeexSDK/Sources/Component/WXImageComponent.m b/ios/sdk/WeexSDK/Sources/Component/WXImageComponent.m
@@ -57,6 +57,7 @@ @interface WXImageComponent ()
     pthread_mutex_t _imageSrcMutex;
     pthread_mutexattr_t _propertMutexAttr;
     BOOL _shouldUpdateImage;
+    BOOL _mainImageSuccess;
 }
 
 @property (atomic, strong) NSString *placeholdSrc;
@@ -398,12 +399,30 @@ - (void)updateImage
     }
     __weak typeof(self) weakSelf = self;
     if (_downloadImageWithURL && [[self imageLoader] respondsToSelector:@selector(setImageViewWithURL:url:placeholderImage:options:progress:completed:)]) {
+        _mainImageSuccess = NO;
+
         NSString *newURL = nil;
         if (self.placeholdSrc) {
             newURL = [self.placeholdSrc copy];
             WX_REWRITE_URL([self placeholdSrc], WXResourceTypeImage, self.weexInstance)
-            NSDictionary* extInfo = @{@"instanceId":[self _safeInstanceId]};
-            [[self imageLoader] setImageViewWithURL:(UIImageView*)self.view url:[NSURL URLWithString:newURL] placeholderImage:nil options:extInfo progress:nil completed:nil];
+            NSDictionary* extInfo = @{@"instanceId":[self _safeInstanceId], @"pageURL": self.weexInstance.scriptURL ?: @""};
+            [[self imageLoader] setImageViewWithURL:(UIImageView*)self.view url:[NSURL URLWithString:newURL] placeholderImage:nil options:extInfo progress:nil completed:^(UIImage *image, NSError *error, WXImageLoaderCacheType cacheType, NSURL *imageURL) {
+                /* We cannot rely on image library even if we call setImage with placeholer before calling setImage with real url.
+                 The placeholder image may be downloaded and decoded after the real url, so finally we show the placeholder image by wrong. */
+                __strong typeof(weakSelf) strongSelf = weakSelf;
+                if (strongSelf) {
+                    UIImageView *imageView = (UIImageView *)strongSelf.view;
+                    if (imageView && imageView.image == image && strongSelf->_mainImageSuccess) {
+                        // reload image with main image url
+                        NSString* newURL = [[strongSelf imageSrc] copy];
+                        WX_REWRITE_URL([strongSelf imageSrc], WXResourceTypeImage, strongSelf.weexInstance)
+                        NSDictionary *userInfo = @{@"imageQuality":@(strongSelf.imageQuality), @"imageSharp":@(strongSelf.imageSharp),  @"blurRadius":@(strongSelf.blurRadius), @"instanceId":[strongSelf _safeInstanceId], @"pageURL": strongSelf.weexInstance.scriptURL ?: @""};
+                        [[strongSelf imageLoader] setImageViewWithURL:imageView url:[NSURL URLWithString:newURL] placeholderImage:nil options:userInfo progress:nil completed:^(UIImage *image, NSError *error, WXImageLoaderCacheType cacheType, NSURL *imageURL) {
+                            WXLogInfo(@"Image re-requested because placeholder may override main image. %@", imageURL);
+                        }];
+                    }
+                }
+            }];
         }
         newURL = [[self imageSrc] copy];
         if ([newURL length] == 0) {
@@ -436,6 +455,10 @@ - (void)updateImage
                                                         completed:nil];
                     return;
                 }
+                strongSelf->_mainImageSuccess = NO;
+            }
+            else {
+                strongSelf->_mainImageSuccess = YES;
             }
             UIImageView *imageView = (UIImageView *)strongSelf.view;
             if (imageView && imageView.image != image) {