Fragment_动态加载

1.新建Fragment的XML布局文件。

2.在activity.xml中添加需要加载Fragment。列如：

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
     tools:context="com.example.administrator.fragment_01.activity.MainActivity">

     <FrameLayout
         android:id="@+id/fragment_id"
         android:layout_width="match_parent"
         android:layout_height="0dp"
         android:layout_weight="1" />

     <LinearLayout
         android:id="@+id/layout_1"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:gravity="bottom"
         android:orientation="horizontal">

         <Button
             android:id="@+id/activity_button_1"
             android:layout_width="0dp"
             android:layout_height="wrap_content"
             android:layout_weight="1"
             android:text="@string/button_1" />

         <Button
             android:id="@+id/activity_button_2"
             android:layout_width="0dp"
             android:layout_height="wrap_content"
             android:layout_weight="1"
             android:text="@string/button_2" />

     </LinearLayout>
 </LinearLayout>

3.创建MyFragment类继承Fragment类。

 public class MyFragment extends Fragment {

     @Override
     public View onCreateView(LayoutInflater inflater,  ViewGroup container,  Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.one_fragment, container,false);
         return view;
     }
 }

4.创建待添加Fragment的实例。

5.获取FragmentManager。

6.开启一个事务。

7.向容器中添加或替换碎。

8.提交事务。

 public class MainActivity extends AppCompatActivity implements View.OnClickListener {

     private Button button;
     private Button button1;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         Button button = (Button) findViewById(R.id.activity_button_1);
         Button button1 = (Button) findViewById(R.id.activity_button_2);
         button.setOnClickListener(this);
         button1.setOnClickListener(this);
             //创建实例做参数穿入。
         replaceFragment(new MyFragment());
     }

     @Override
     public void onClick(View view) {

         switch (view.getId()) {
             case R.id.activity_button_1:
                 replaceFragment(new MyFragment_2());
                 Toast.makeText(this, "点击了第一个", Toast.LENGTH_SHORT).show();
                 break;
             case R.id.activity_button_2:
                 replaceFragment(new MyFragment());
                 Toast.makeText(this, "点击了第二个", Toast.LENGTH_SHORT).show();
                 break;
         }
     }

     private void replaceFragment(Fragment fragment) {
              //2.获取FragmentManager.
         FragmentManager fragmentManager = getSupportFragmentManager();
         //3.开启一个事务beginTransaction()
         FragmentTransaction transaction = fragmentManager.beginTransaction();
         //向容器中添加或替换碎片
         transaction.replace(R.id.fragment_id, fragment);
         //提交事务
         transaction.commit();
     }
 }