• 方法一：直接getActivity，使用activity的fragmenttransation的replace方法替換
  假設

    class OneFragment extends Fragment{
    	private Button btn;
    	@Override
    	public View onCreateView(LayoutInflater inflater, ViewGroup container,
    			Bundle savedInstanceState) {
    		View view = inflater.inflate(R.layout.frag_one, null);
    		btn = (Button)view.findViewById(R.id.button);
    		btn.setOnClickListener(new OnClickListener() {
    			
    			@Override
    			public void onClick(View v) {
    				FragmentManager fm = getActivity().getFragmentManager();
    				fm.beginTransaction()
    				//替換為TwoFragment
    				.replace(R.layout.fragment_container,new TwoFragment())
    				.commit();
    			}
    		});
    		return super.onCreateView(inflater, container, savedInstanceState);
    	}
    }
   
  

但是這樣做會使OneFragment和原activity的耦合度提高,fragment設計出來就是有重用的目的，所以不好，使用方法二

• 方法2：定義回撥函式，當button按下呼叫回撥

    class OneFragment extends Fragment{
    	private Button btn;
    	private OnButtonClick onButtonClick;
    	@Override
    	public View onCreateView(LayoutInflater inflater, ViewGroup container,
    			Bundle savedInstanceState) {
    		View view = inflater.inflate(R.layout.frag_one, null);
    		btn = (Button)view.findViewById(R.id.button);
    		btn.setOnClickListener(new OnClickListener() {
    			
    			@Override
    			public void onClick(View v) {
    				if(onButtonClick!=null){
    					onButtonClick.onClick(btn);
    				}
    			}
    		});
    		return super.onCreateView(inflater, container, savedInstanceState);
    	}
    	public OnButtonClick getOnButtonClick() {
    		return onButtonClick;
    	}
    	public void setOnButtonClick(OnButtonClick onButtonClick) {
    		this.onButtonClick = onButtonClick;
    	}
    	public interface OnButtonClick{
    		public void onClick(View view);
    	}
    }
   
  

  這樣只要在acitivty中設定回撥即可

    public class MainActivity extends Activity {
    
    	private OneFragment oneFragment = new OneFragment();
    	@Override
    	protected void onCreate(Bundle savedInstanceState) {
    		super.onCreate(savedInstanceState);
    		setContentView(R.layout.activity_main);
    		//。。。
    		//。。。省略程式碼
    		oneFragment.setOnButtonClick(new OnButtonClick() {
    			
    			@Override
    			public void onClick(View view) {
    				//切換到TwoFragment
    				fm.beginTransaction()
    				//替換為TwoFragment
    				.replace(R.layout.fragment_container,new TwoFragment())
    				.commit();
    			}
    		});
    	}
    }