In-depth analysis: fragment and Activity Interaction methods (3) use interfaces)

Step 1: Define an interface in fragment and make sure that our container activity implements this interface:

Public interface ontestlistener {
Public void ontest (string Str);
}< br> @ override
Public void onattach (activity) {
super. onattach (activity);
// This method is used to check whether the current activity container inherits this interface, if no exception is thrown,
try {
mcallback = (ontestlistener) activity;
} catch (classcastexception E) {
throw new classcastexception (activity. tostring ()
+ "must implement onheadlineselectedlistener ");
}< br> }< br>

Step 2: implement this interface in our container activity and implement the methods in the interface.

Public class mainactivity extends activity implements ontestlistener {

......

@ Override
Public void ontest (string Str ){
Text. settext (STR );
}

Step 3: Call the methods declared in the interface when we perform certain operations in fragment.

@ Override
Public void onclick (view v ){
Mcallback. ontest (edit. gettext (). tostring ());
}

Link to the complete code: http://download.csdn.net/detail/huangyabin001/7560291click to open the link