I'm building an QR Code Scanner using gms Vision API. The scanner is working properly, but as soon as I try to replace the fragment, it's not getting replaced, it's getting added.
Code to replace:
val manager: FragmentManager? = (context as MainActivity).supportFragmentManager
val transaction: FragmentTransaction? = manager?.beginTransaction()
transaction?.replace(R.id.container, ScannedFragment())
transaction?.addToBackStack(null)
transaction?.commit()
There are no error messsages. The app looks like this then:
Image
I found the solution myself. I had to use a FrameLayout to replace.
I want to navigate between pages be starting and finishing new activity for any new page and show this page in own activity. How to achieve this behavior?
The answer is Yes,you could look at Native Forms.
For ios:
in ios project AppDelegate
public override bool FinishedLaunching(UIApplication application, NSDictionary launchOptions)
{
Forms.Init();
...
UIViewController mainPage = new NotesPage().CreateViewController();
mainPage.Title = "Notes";
_navigation = new AppNavigationController(mainPage);
_window.RootViewController = _navigation;
_window.MakeKeyAndVisible();
return true;
}
For Android:
in Android project your activity ,it convert your page to a fragment,and then you could fill it in your activity:
Android.Support.V4.App.Fragment mainPage = new NotesPage().CreateSupportFragment(this);
SupportFragmentManager
.BeginTransaction()
.Replace(Resource.Id.fragment_frame_layout, mainPage)
.Commit();
On Android Xamarin.Forms navigate among pages by using Fragments.
If you don't like it you may fork Xamarin.Forms and change the code to work the way you want it to work: https://github.com/xamarin/Xamarin.Forms
This will make some packages incompatible with your fork of Xamarin.Forms, which you may need to take under consideration if you intend to use them.
Also if you consider the required time and knowledge this is non-trivial. It is highly unlikely that someone will do that job instead of you and provide you with the plug-in solution.
I'm trying to animate the showing of a fragment in a very basic way but it doesn't work:
MyFragment myFragment = (MyFragment) getFragmentManager().findFragmentById(R.id.myFragment);
getFragmentManager().beginTransaction()
.hide(myFragment)
.commit();
Slide slideRight = new Slide(Gravity.RIGHT);
slideRight.setDuration(3000);
Slide slideLeft = new Slide(Gravity.LEFT);
slideLeft.setDuration(3000);
myFragment.setEnterTransition(slideRight);
myFragment.setExitTransition(slideLeft);
then later
getFragmentManager().beginTransaction()
.show(myFragment)
.commit();
But fragment just appears without any transition. I can't figure out why it doesn't animate.
Edit:
I ended up using the fragment support library with setCustomAnimations cause the native library doesn't support animation with relative values.
Also using the new API with setEnterTransition doesn't seem to work properly with show/hide and for some unknown reason worked only with replace which doesn't fit my needs.
setCustomAnimation will do the trick.
FragmentManager.beginTransaction()
.replace(R.id.fragment, new Fragment)
.setCustomAnimations(R.anim.slide_out_left, R.anim.slide_in_right).commit();
I have migrated my application to Android O in Android Studio 3
Running on an Android O emulator all my dialogFragments now fail with :-
java.lang.IllegalStateException: Fragment MyDialogFragment{43ccf50 #2 MyDialogFragment} declared target fragment SettingsFragment{ceed549 #0 id=0x7f0f0142 android:switcher:2131689794:0} that does not belong to this FragmentManager!
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1316)
at android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1624)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1689)
at android.support.v4.app.BackStackRecord.executeOps(BackStackRecord.java:794)
at android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2470)
at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2260)
at android.support.v4.app.FragmentManagerImpl.optimizeAndExecuteOps(FragmentManager.java:2213)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2122)
at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:746)
at android.os.Handler.handleCallback(Handler.java:769)
at android.os.Handler.dispatchMessage(Handler.java:98)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6535)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
I have made no code changes whatsoever.
What has changed in Android O that previously working DialogFragments now fail display?
Android Studio 3.0 Canary 1
Build #AI-171.4010489, built on May 15, 2017
JRE: 1.8.0_112-release-b736 x86_64
JVM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
Mac OS X 10.11.6
compileSdkVersion 'android-O'
buildToolsVersion "26.0.0-rc2"
AndroidManifest.xml
defaultConfig {
minSdkVersion 16
targetSdkVersion 'O'
}
compile 'com.android.support:appcompat-v7:26.0.0-beta1'
compile 'com.android.support:cardview-v7:26.0.0-beta1'
compile 'com.android.support:design:26.0.0-beta1'
compile 'com.android.support:percent:26.0.0-beta1'
dependencies {
classpath 'com.android.tools.build:gradle:3.0.0-alpha1'
}
For me this was not only an issue on Android O but also on older versions.
The oldest version I tested was API Level 16.
I was instantiating my fragments using this code:
MyFragment myFragment = MyFragment.newInstance();
myFragment.setTargetFragment(ParentFragment.this, 0);
myFragment.show(getActivity().getSupportFragmentManager(), null);
Where ParentFragment.this is a custom class extending android.support.v4.app.Fragment, MyFragment also extends this class and is a child fragment of the ParentFragment fragment (hence it's name).
I thought that I had to use a SupportFragmentManager (the getSupportFragmentManager() method) because I am using a fragment of the support package so I tried to call getActivity().getSupportFragmentManager() to get an activity reference that supported this method.
This does not seem to be the correct way though.
I changed those calls to:
MyFragment myFragment = MyFragment.newInstance();
myFragment.setTargetFragment(ParentFragment.this, 0);
myFragment.show(getFragmentManager(), null);
so the fragment decides on it's own which FragmentManager to use and the error is gone now.
Hope this helps someone.
I had the same problem, definitely an android bug. It happens when you are showing a fragment from another fragment using it as target. As workaround you can use:
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
getActivity().getFragmentManager().beginTransaction().add(dialogFrag, "dialog").commit();
else
getChildFragmentManager().beginTransaction().add(dialogFrag,"dialog").commit();
I just faced the same issues in the project that I am currently working on when we moved to Android Studio 3 and upgraded the support library to version 26. All of a sudden, without changing the code, we got tons of this exception. In the end I found out the following:
Google added a new "sanity check" in the sources of the v4 Fragment Manager in January this year (not sure into what release that went) that refuses to add a fragment using a Fragment Manager, if it has a target fragment set and the target fragment cannot be found in the active fragments of the same Fragment Manager. The patch is described in detail here
Ealier versions seem to not have cared about that. Took me a few days to update all the areas in our code where fragments that were added using the Support Fragment Manager used the Child Fragment Manager for their subfragments with the parent fragment as target. Well, late penalty for writing bad code.
I had the same case as Markus Ressel but I was using getChildFragmentManager(). I replaced that with getFragmentManager() and it resolved the issue.
UPDATE: I've now been working with childFragmentManager and have some feedback.
When dealing with inner fragments that are hosted by a fragment (so a fragment within a fragment) use the childFragmentManager. This fragment manager differs from the activities getSupportFragmentManager. The two are not the same. It's a separation of concerns.
So I've made a rule that fragments hosting child fragments will always use the childFragmentManager and things not inside host fragments can use getSupportfragmentManager.
Recently, my app experienced the same issue when I targeted it for Android O. As a solution, use:
myDialogFragment.show(SettingsFragment.this.getFragmentManager(), TAG);
instead of:
myDialogFragment.show(getFragmentManager(), TAG);
// or
myDialogFragment.show(getSupportFragmentManager(), TAG);
// or
myDialogFragment.show(getChildFragmentManager(), TAG);
while working on an app, I encountered the same problem and I solved it by (in kotlin)
chooseRegionFragment.setTargetFragment(this#ParentFragment, REQUEST_CODE_CHOOSE_REGION)
chooseRegionFragment.show(this#ParentFragment.parentFragmentManager, TAG)
it translates to
chooseRegionFragment.setTargetFragment(ParentFragment.this, REQUEST_CODE_CHOOSE_REGION);
chooseRegionFragment.show(ParentFragment.this.getParentFragmentManager, TAG);
in java
my app work well until upgrade target version to 27 then i face same issue when call setTargetFragment (Fragment fragment,
int requestCode)
example:
chooseRegionFragment.setTargetFragment(ParentFragment.this, REQUEST_CODE_CHOOSE_REGION);
just change to:
chooseRegionFragment.setTargetFragment(getRootParentFragment(this), REQUEST_CODE_CHOOSE_REGION);
getRootParentFragment(this) this method will find root parent of fragments for you
/**
* find root parent of fragment
*/
public static Fragment getRootParentFragment(Fragment fragment) {
Fragment parent = fragment.getParentFragment();
if(parent == null)
return fragment;
else
return getRootParentFragment(parent);
}
Use below solution and you do not need to worry about which fragment managers you are dealing with,
Assuming that you must have used a BaseFragment.
First create an interface:
public interface OnRequestUpdateListener {
void onRequestUpdate(final int requestCode, final Intent data);
void setRequestFragment(final BaseFragment requestFragment, int requestCode);
BaseFragment getRequestFragment();
int getRequestCode();
}
Implement that interface in your BaseFragment
public class BaseFragment extends Fragment implements OnRequestUpdateListener {
private BaseFragment requestFragment;
private int requestCode;
#Override
public void onRequestUpdate(int requestCode, Intent data) {
// you can implement your logic the same way you do in onActivityResult
}
#Override
public void setRequestFragment(BaseFragment requestFragment, int requestCode) {
this.requestFragment = requestFragment;
this.requestCode = requestCode;
}
#Override
public BaseFragment getRequestFragment() {
return requestFragment;
}
#Override
public int getRequestCode() {
return requestCode;
}
}
Then, replace the setTargetFragment with setRequestFragment and replace getTargetFragment with getRequestFragment.
Here, you could also user onRequestUpdate in place of onActivityResult.
This is a custom solution without bothering about the which fragment manager you are using.
Using getFragmentManager() instead of getChildFragmentManager() would also work but it affects getParentFragment(). If you do not use a getChildFragmentManager() for nested fragment then you will not be able the get the parent fragment by using getParentFragment() in child/nested fragment.
I want to use it in a v4.Fragment to load childFragment, and the SpringIndicator sample code based on MultipleModel.
I tryed to deliver a ChildFragmentManager to ModelPagerAdapter in Fragment follow this:
ModelPagerAdapter adapter = new ModelPagerAdapter(getChildFragmentManager(), new PagerModelManager());
But that not works, nothing displayed on phone's screen.
Actually,The SpringIndicator will works in a Activity.(use getSupportFragmentManager as the arg)
How can I do?Thank you very much.
Sorry,everyBody.That code in question taked effect but not display beacause of background color.So, You can use SpringIndicator in Fragment to load childFragment with:
ModelPagerAdapter adapter = new ModelPagerAdapter(getChildFragmentManager(), new PagerModelManager());
The first arg is getChildFragmentManager() worked for me.