Android的Fragment中onActivityResult不被調用的解決方案(絕對管用)

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常見的，我們會在FragmentActivity中嵌套一層Fragment使用，甚至Fragment下層層嵌套使用。這個時候，在第二級或者更深層級的Fragment將無法收到onActivityResult回調，查看FragementActivity的源碼發現：

public void startActivityFromFragment(Fragment fragment, Intent intent,   :             int requestCode) { :         if (requestCode == -1) { :             super.startActivityForResult(intent, -1); :             return; :         } :         if ((requestCode&0xffff0000) != 0) { :             throw new IllegalArgumentException("Can only use lower 16 bits for requestCode"); :         } :         super.startActivityForResult(intent, ((fragment.mIndex+1)<<16) + (requestCode&0xffff)); :     } :     @Override :     protected void onActivityResult(int requestCode, int resultCode, Intent data) { :         mFragments.noteStateNotSaved(); :         int index = requestCode>>16; :         if (index != 0) { :             index--; :             if (mFragments.mActive == null || index < 0 || index >= mFragments.mActive.size()) { :                 Log.w(TAG, "Activity result fragment index out of range: 0x" :                         + Integer.toHexString(requestCode)); :                 return; :             } :             Fragment frag = mFragments.mActive.get(index); :             if (frag == null) { :                 Log.w(TAG, "Activity result no fragment exists for index: 0x" :                         + Integer.toHexString(requestCode)); :             } else { :                 frag.onActivityResult(requestCode&0xffff, resultCode, data); :             } :             return; :         } :           :         super.onActivityResult(requestCode, resultCode, data); :     } :   

原來，程式猿偷懶，沒有處理嵌套Fragment的情況，也就是說回調只到第一級Fragment，就沒有繼續分發。我們可以實現一個自己的FragmentActiviy，來實現繼續分發，如下：

public class BaseFragmentActiviy extends FragmentActivity { private static final String TAG = "BaseActivity"; @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) {  FragmentManager fm = getSupportFragmentManager();  int index = requestCode >> 16;  if (index != 0) {   index--;   if (fm.getFragments() == null || index < 0     || index >= fm.getFragments().size()) {    Log.w(TAG, "Activity result fragment index out of range: 0x"      + Integer.toHexString(requestCode));    return;   }   Fragment frag = fm.getFragments().get(index);   if (frag == null) {    Log.w(TAG, "Activity result no fragment exists for index: 0x"      + Integer.toHexString(requestCode));   } else {    handleResult(frag, requestCode, resultCode, data);   }   return;  } } /**  * 遞迴調用，對所有子Fragement生效  *   * @param frag  * @param requestCode  * @param resultCode  * @param data  */ private void handleResult(Fragment frag, int requestCode, int resultCode,   Intent data) {  frag.onActivityResult(requestCode & 0xffff, resultCode, data);  List<Fragment> frags = frag.getChildFragmentManager().getFragments();  if (frags != null) {   for (Fragment f : frags) {    if (f != null)     handleResult(f, requestCode, resultCode, data);   }  } }

然後我們繼承這個BaseFragmentActivity即可，但是要注意，在Fragment中啟動Activity時，一定要調用根Fragment的啟動方法，如下：

/**  * 得到根Fragment  *   * @return  */ private Fragment getRootFragment() {  Fragment fragment = getParentFragment();  while (fragment.getParentFragment() != null) {   fragment = fragment.getParentFragment();  }  return fragment; } /**  * 啟動Activity  */ private void onClickTextViewRemindAdvancetime() {  Intent intent = new Intent();  intent.setClass(getActivity(), YourActivity.class);  intent.putExtra("TAG","TEST");   getRootFragment().startActivityForResult(intent, 1001); }

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Android的Fragment中onActivityResult不被調用的解決方案(絕對管用)