Hallo!
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if ( Array.isArray( propertyNames ) ) { |
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cacheKey = propertyNames.join( "->" ); |
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// Ensure cached identity function. |
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if ( ! cache[ cacheKey ] ) { |
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cache[ cacheKey ] = function trackByProperty<T>( index: number, item: T ) : any { |
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var values = []; |
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// Collect the item values that will be aggregated in the resultant |
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// item identity |
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for ( var propertyName of propertyNames ) { |
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values.push( item[ propertyName ] ); |
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} |
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return( values.join( "->" ) ); |
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}; |
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} |
This part for a list of properties doesn't work correctly.
the list will be re'rendered each time if I click on refresh button with the same data. If I move the code into separate function and use directly on trackBy, then the list will be never re'rendered...
any Idea?
Outputs:
on start:
after click on refresh button:
