[Android] news client realizes left navigation and click switching

Set the main layout file and set an ID for the root layout as the content area

Set the click event for the listview entry, setonitemclicklistener() method, parameter: Context

The current fragment implements the onitemclicklistener interface

Implement the onitemclick() method

Switch judges the index position of the current menu and instantiates different fragment objects according to the index

Call getactivity () method to get the host activity object. This activity exposes a method to replace the fragment

Use the keyword instances of to judge that getactivity() gets an instance of mainactivity class

Call the switchmenufragment() method of the host activity object to switch the fragment of the content part. Parameter: fragment object

Host activity exposure method switchmenufragment(), switch content area fragment, parameter: fragment object

getSupportFragmentManager().beginTransaction().replace(R.id.ll_main_content,fragment).commit();

Call the toggle () method of the slidingmenu object to close the left menu

Set the default to display the contents of the first navigation when the app is opened for the first time

MainActivity

MenuFragment.java