一个Fragment必须总是被嵌入到一个Activity中,它的生命周期直接被其所属的宿主Activity生命周期影响,它的状态会随宿主的状态变化而变化。
要创建一个Fragment 必须创建一个Fragment的子类,或者继承自另一个已经存在的Fragment的子类.并重写onCreateView()方法加载UI。
静态加载两个Fragment,左边显示三个Button,右边显示一个TextView
1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 2 xmlns:tools="http://schemas.android.com/tools" 3 android:id="@+id/activity_main" 4 android:layout_width="match_parent" 5 android:layout_height="match_parent" 6 android:orientation="vertical" 7 tools:context="com.example.lesson10_fragment.MainActivity"> 8 9 <fragment 10 android:tag="fragment1" 11 android:name="com.example.lesson10_fragment.Fragment1" 12 android:layout_width="match_parent" 13 android:layout_height="wrap_content" /> 14 15 16 <fragment 17 android:tag="fragment2" 18 android:name="com.example.lesson10_fragment.Fragment2" 19 android:layout_width="match_parent" 20 android:layout_height="wrap_content" /> 21 22 </LinearLayout>
activity_main.xml
1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 2 android:layout_width="match_parent" 3 android:layout_height="match_parent" 4 android:orientation="vertical"> 5 6 <Button 7 android:layout_width="wrap_content" 8 android:layout_height="wrap_content" 9 android:text="Button1"/> 10 <Button 11 android:layout_width="wrap_content" 12 android:layout_height="wrap_content" 13 android:text="Button2"/> 14 <Button 15 android:layout_width="wrap_content" 16 android:layout_height="wrap_content" 17 android:text="Button3"/> 18 </LinearLayout>
frag1_layout.xml
1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 2 android:layout_width="match_parent" 3 android:layout_height="match_parent"> 4 5 <TextView 6 android:layout_width="wrap_content" 7 android:layout_height="wrap_content" 8 android:text="哈哈哈啊哈哈" 9 android:textSize="50sp" 10 android:layout_centerInParent="true"/> 11 12 </RelativeLayout>
frag2_layout.xml
1 public class Fragment1 extends Fragment{ 2 3 @Override 4 public void onAttach(Context context) { 5 super.onAttach(context); 6 Log.e("TAG","----------Fragment1----onAttach"); 7 } 8 9 @Override 10 public void onCreate(@Nullable Bundle savedInstanceState) { 11 super.onCreate(savedInstanceState); 12 Log.e("TAG","----------Fragment1----onCreate"); 13 } 14 15 @Nullable 16 @Override 17 public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { 18 View layout = View.inflate(getActivity(),R.layout.frag1_layout,null); 19 //由于这super.onCreateView(inflater, container, savedInstanceState)返回的是null,所以不能用 20 21 Log.e("TAG","----------Fragment1----onCreateView"); 22 return layout; 23 } 24 25 @Override 26 public void onActivityCreated(@Nullable Bundle savedInstanceState) { 27 super.onActivityCreated(savedInstanceState); 28 Log.e("TAG","----------Fragment1----onActivityCreated"); 29 } 30 31 @Override 32 public void onStart() { 33 super.onStart(); 34 Log.e("TAG","----------Fragment1----onStart"); 35 } 36 37 @Override 38 public void onResume() { 39 super.onResume(); 40 Log.e("TAG","----------Fragment1----onResume"); 41 } 42 43 @Override 44 public void onPause() { 45 super.onPause(); 46 Log.e("TAG","----------Fragment1----onPause"); 47 } 48 49 @Override 50 public void onStop() { 51 super.onStop(); 52 Log.e("TAG","----------Fragment1----onStop"); 53 } 54 55 @Override 56 public void onDestroyView() { 57 super.onDestroyView(); 58 Log.e("TAG","----------Fragment1----onDestroyView"); 59 } 60 61 @Override 62 public void onDestroy() { 63 super.onDestroy(); 64 Log.e("TAG","----------Fragment1----onDestroy"); 65 } 66 67 @Override 68 public void onDetach() { 69 super.onDetach(); 70 Log.e("TAG","----------Fragment1----onDetach"); 71 } 72 }
Fragment1.java
1 public class Fragment2 extends Fragment{ 2 3 @Nullable 4 @Override 5 public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { 6 View layout = View.inflate(getActivity(),R.layout.frag2_layout,null); 7 return layout; 8 } 9 }
Fragment2.java
1 public class MainActivity extends AppCompatActivity { 2 3 @Override 4 protected void onCreate(Bundle savedInstanceState) { 5 super.onCreate(savedInstanceState); 6 setContentView(R.layout.activity_main); 7 Log.e("TAG","---MainActivity----onCreate"); 8 } 9 10 @Override 11 protected void onStart() { 12 super.onStart(); 13 Log.e("TAG","---MainActivity----onStart"); 14 } 15 16 @Override 17 protected void onResume() { 18 super.onResume(); 19 Log.e("TAG","---MainActivity----onResume"); 20 } 21 22 @Override 23 protected void onPause() { 24 super.onPause(); 25 Log.e("TAG","---MainActivity----onPause"); 26 } 27 28 @Override 29 protected void onStop() { 30 super.onStop(); 31 Log.e("TAG","---MainActivity----onStop"); 32 } 33 34 @Override 35 protected void onDestroy() { 36 super.onDestroy(); 37 Log.e("TAG","---MainActivity----onDestroy"); 38 } 39 40 @Override 41 protected void onRestart() { 42 super.onRestart(); 43 Log.e("TAG","---MainActivity----onRestart"); 44 } 45 }
MainActivity.java
运行之后
时间: 2024-08-27 12:41:04