Android測試Activity和Fragment的生命週期
阿新 • • 發佈:2019-01-03
Activity的生命週期有7個函式,Fragment的生命週期有11個函式。
Activity生命週期除上述6個方法還有一個Restart()方法,該方法在該Activity從不可見(仍存在)到重新可見時呼叫。
測試程式碼如下:
import android.app.Activity; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v7.app.AppCompatActivity; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Log.i("info","Activity--onCreate()"); setContentView(R.layout.activity_main); android.app.Fragment tFragment = new TFragment(); getFragmentManager().beginTransaction().add(R.id.FLayout,tFragment).commit(); } @Override protected void onStart() { super.onStart(); Log.i("info","Activity--onStart()"); } @Override protected void onResume() { super.onResume(); Log.i("info","Activity--onResumed()"); } @Override protected void onPause() { super.onPause(); Log.i("info","Activity--onPause()"); } @Override protected void onStop() { super.onStop(); Log.i("info","Activity--onStop()"); } @Override protected void onRestart() { super.onRestart(); Log.i("info","Activity--onRestart()"); } @Override protected void onDestroy() { super.onDestroy(); Log.i("info","Activity--onDestroy()"); } public static class TFragment extends android.app.Fragment{ @Override public void onAttach(Activity activity) { super.onAttach(activity); Log.e("info","Fragment--onAttach()"); } @Override public void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); Log.e("info","Fragment--onCreate()"); } @Nullable @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { Log.e("info","Fragment--onCreateView()"); return super.onCreateView(inflater, container, savedInstanceState); } @Override public void onActivityCreated(@Nullable Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); Log.e("info","Fragment--onActivityCreated()"); } @Override public void onStart() { super.onStart(); Log.e("info","Fragment--onStart()"); } @Override public void onResume() { super.onResume(); Log.e("info","Fragment--onResume()"); } @Override public void onPause() { super.onPause(); Log.e("info","Fragment--onPause()"); } @Override public void onStop() { super.onStop(); Log.e("info","Fragment--onStop()"); } @Override public void onDestroyView() { super.onDestroyView(); Log.e("info","Fragment--onDestroyView()"); } @Override public void onDestroy() { super.onDestroy(); Log.e("info","Fragment--onDestroy()"); } @Override public void onDetach() { super.onDetach(); Log.e("info","Fragment--onDetach()"); } } }
佈局程式碼:
<?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:id="@+id/activity_main" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context="com.example.asus.animport.MainActivity"> <FrameLayout android:id="@+id/FLayout" android:layout_width="match_parent" android:layout_height="match_parent"> </FrameLayout> </LinearLayout>
可以看出:各過程的執行結果與第一張圖Activity與Fragment生命週期的方法對應一致,特別需要注意的是,由於Fragment依賴Activity的存在而存在,故在建立時Activity生命週期中的方法均先於Fragment生命週期中的方法執行;相反,在銷燬時,是先執行Fragment生命週期中的方法再執行Activity生命週期中的方法。
(參考資料:http://www.2cto.com/kf/201512/453242.html;http://blog.csdn.net/zjclugger/article/details/10442335)
值得一提的是,Fragment生命週期中的方法onAttach(Context context)在執行該程式中並沒有執行,查閱資料發現在API低於23的版本中不會執行該方法,而是執行onAttach(Activity Activity)。(參考資料: http://blog.csdn.net/cadi2011/article/details/53314055)