android - Some confusion on the method instantiateItem(ViewGroup container, int position) of PagerAdapter -

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public object instantiateitem(viewgroup container, int position) {       imageview view = new imageview();       container.addview(view);       return view; }

i read example code of pageradapter, , write addview method. above simple code, , know 'return view' used return view display, container.addview(view) do?

adding view container makes appear on-screen. object returned instantiateitem key/identifier; happens using actual view purpose tends convenient if aren't using fragment manage view page. (see source fragmentpageradapter example.)

the pageradapter method isviewfromobject helps pager know view belongs key. if you're returning view key object, can implement method trivially as:

public boolean isviewfromobject(view view, object object) {     return view == object; }

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