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PONSOutlineView rowForItem: always returns 0
 

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  1. PONSOutlineView rowForItem: always returns 0
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    <p>I have an app which needs to update cells in certain columns asynchronously. I have a GCD queue which blocks are added to which later gets the cell for the row and column given using <code>-rowForItem:</code> but the result of <code>-rowForItem:</code> is consistently 0, and <code>NSAssert([self.outlineView itemAtRow:row] == item, @"rowForItem: and itemForRow: not reversible! (Item %@, row %ld)", item, (long)row);</code> throws every time. I don't see what I'm doing wrong here. The index is not -1, which means that the item wasn't found, but the item is said to be at the incorrect index. (The first item is always a JODirectoryInfo, and I only run the block on JOFileInfo, so it can't be the wrong item.)</p> <pre><code>- (NSTableCellView *)_cellForRow:(NSInteger)row columnIdentifier:(NSString *)column { if (row &lt; 0) return nil; NSInteger colIdx = [self.outlineView columnWithIdentifier:column]; if (colIdx == -1) return nil; if (colIdx + 1 &gt; self.outlineView.tableColumns.count) return nil; return [self.outlineView viewAtColumn:colIdx row:row makeIfNecessary:NO]; } - (NSTableCellView *)_cellForItem:(id)item columnIdentifier:(NSString *)column { NSInteger row = [self.outlineView rowForItem:item]; NSAssert([self.outlineView itemAtRow:row] == item, @"rowForItem: and itemForRow: not reversible! (Item %@, row %ld)", item, (long)row); DDLogVerbose(@"Getting cell for item %@ (row %ld) in column %@", item, (long)row, column); return [self _cellForRow:row columnIdentifier:column]; } - (dispatch_block_t)_loadingBlockForItem:(JOFileInfo *)item block:(JOFileInfoBlock)block column:(NSString *)columnIdentifier { return ^{ NSTableCellView *cellView = [self _cellForItem:item columnIdentifier:columnIdentifier]; if (!cellView) return; cellView.objectValue = block(item); }; } - (id)outlineView:(NSOutlineView *)outlineView objectValueForTableColumn:(NSTableColumn *)tableColumn byItem:(id)item { DDLogVerbose(@"Requested value of column %@ for item %@", tableColumn.identifier, item); if ([tableColumn.identifier isEqualToString:@"Size"]) { if ([item isKindOfClass:[JOFileInfo class]]) { dispatch_async(self.queue, [self _loadingBlockForItem:item block:^(JOFileInfo *item) { unsigned long long size = item.size; if (size != ULONG_LONG_MAX) return [self.byteCountFormatter stringFromByteCount:size]; else return @"--"; } column:tableColumn.identifier]); return @"--"; } else { return @"--"; } } else { return @"text"; } } </code></pre>
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    1. USJosh The Geek
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      1. PONSOutlineView rowForItem: always returns 0
      1. USJosh The Geek
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    1. This table or related slice is empty.
 

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