UITextView related issues

UITextView automatically change the height based on the contents written. Which heroes know not, under detailed trouble code.
Reply:
You can use a third-party open source libraries: HPGrowingTextView
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cited a floor reply:

can use third-party open source libraries: HPGrowingTextView

Can explain? Thanks
Reply:
There NSString string functions can calculate the height of the first call which calculates the required string to be displayed and then dynamically change the size of the textview
Reply:
check it:
https://github.com/HansPinckaers/GrowingTextView/
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A detailed talk on iphone / ipad development tutorial