Tag: fragmentmanager

我如何访问片段中的getSupportFragmentManager（）？

我有一个FragmentActivity，我想使用它内的地图片段。 我有一个问题让支持片段管理器来访问它。 if (googleMap == null) { googleMap = ((SupportMapFragment) getSupportFragmentManager() .findFragmentById(R.id.map1)).getMap(); // check if map is created successfully or not if (googleMap == null) { Toast.makeText(getApplicationContext(), "Sorry! unable to create maps", Toast.LENGTH_SHORT) .show(); } } // create marker MarkerOptions marker = new MarkerOptions().position( new LatLng(latitude, longitude)).title("Hello Maps "); CameraPosition cameraPosition = new CameraPosition.Builder() .target(new […]

在提交FragmentTransaction之前检查状态是否保存

我有时会看到下面的堆栈跟踪提交，当用户没有看到活动（在状态被保存之后）时可能发生： java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState at android.support.v4.app.FragmentManagerImpl.checkStateLoss(FragmentManager.java:1327) at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1338) at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:595) at android.support.v4.app.BackStackRecord.commit(BackStackRecord.java:574) 看一下Android的源代码，这是非常重要的： private void checkStateLoss() { if (mStateSaved) { throw new IllegalStateException( "Can not perform this action after onSaveInstanceState"); } if (mNoTransactionsBecause != null) { throw new IllegalStateException( "Can not perform this action inside of " + mNoTransactionsBecause); } […]