[android] 新聞用戶端實現左側導航點擊切換

標籤：

設定主布局檔案，為根布局設定一個id，作為內容區

 

給ListView的條目設定點擊事件，setOnItemClickListener()方法，參數：上下文

當前的Fragment實現OnItemClickListener介面

實現onItemClick()方法

switch判斷一下當前菜單的索引位置，根據索引來執行個體化不同的Fragment對象

調用getActivity()方法，得到宿主Activity對象，這個activity暴露一個方法，替換fragment

使用關鍵字instances of判斷getActivity()得到的是MainActivity類的執行個體

調用宿主Activity對象的switchMenuFragment()方法，切換內容部分的fragment，參數：Fragment對象

 

宿主activity暴露方法switchMenuFragment()，切換內容區fragment，參數：Fragment對象

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

調用SlidingMenu對象的toggle()方法，關閉左側菜單

 

設定預設，當app第一次開啟時顯示導航第一個的內容

MainActivity

 

package com.qingguow.news;import android.os.Bundle;import android.support.v4.app.Fragment;import android.support.v4.app.FragmentTransaction;import android.view.Window;import com.jeremyfeinstein.slidingmenu.lib.SlidingMenu;import com.jeremyfeinstein.slidingmenu.lib.app.SlidingFragmentActivity;import com.qingguow.news.fragment.IndexFragment;import com.qingguow.news.fragment.MenuFragment;public class MainActivity extends SlidingFragmentActivity {    private SlidingMenu sm;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        requestWindowFeature(Window.FEATURE_NO_TITLE);        //設定滑動菜單        setBehindContentView(R.layout.menu);        setContentView(R.layout.activity_main);        sm=getSlidingMenu();        sm.setMode(SlidingMenu.LEFT);        sm.setBehindWidth(200);        sm.setShadowDrawable(R.drawable.shape);        sm.setShadowWidth(5);        sm.setTouchModeAbove(SlidingMenu.TOUCHMODE_FULLSCREEN);                FragmentTransaction ft=getSupportFragmentManager().beginTransaction();        //替換導航fragemnt        MenuFragment menuFragment=new MenuFragment();        ft.replace(R.id.ll_left_menu, menuFragment);        //替換內容fragment        IndexFragment index=new IndexFragment();        ft.replace(R.id.ll_main_content, index).commit();            }    /**     * 暴露方法切換內容區     * @param fragment     */    public void switchMenuFragment(Fragment fragment){        getSupportFragmentManager().beginTransaction().replace(R.id.ll_main_content, fragment).commit();        sm.toggle();    }}

 

MenuFragment.java

package com.qingguow.news.fragment;import java.util.ArrayList;import java.util.List;import android.app.Activity;import android.os.Bundle;import android.support.annotation.Nullable;import android.support.v4.app.Fragment;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.AdapterView;import android.widget.AdapterView.OnItemClickListener;import android.widget.ArrayAdapter;import android.widget.ListAdapter;import android.widget.ListView;import com.qingguow.news.MainActivity;import com.qingguow.news.R;public class MenuFragment extends Fragment implements OnItemClickListener {    private View view;    //載入布局檔案    @Override    public View onCreateView(LayoutInflater inflater,            @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {        view = inflater.inflate(R.layout.list_view, null);        return view;    }    //設定listview資料    @Override    public void onActivityCreated(@Nullable Bundle savedInstanceState) {        super.onActivityCreated(savedInstanceState);        ListView listview = (ListView) view.findViewById(R.id.lv_menu);                List<String> data=new ArrayList<String>();        data.add("新聞");        data.add("發現");        data.add("關注");        ListAdapter adapter = new ArrayAdapter<>(getActivity(),                android.R.layout.simple_list_item_1, android.R.id.text1,                data);        listview.setAdapter(adapter);        listview.setOnItemClickListener(this);            }    /**     * 導航點擊     */    @Override    public void onItemClick(AdapterView<?> parent, View view, int position,            long id) {        Fragment fragment=null;        switch (position) {        case 0:            fragment=new IndexFragment();            break;        default:            break;        }        if(fragment!=null){            Activity activity=getActivity();            if(activity instanceof MainActivity){                ((MainActivity) activity).switchMenuFragment(fragment);            }        }    }}

 

[android] 新聞用戶端實現左側導航點擊切換