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using Android.App;
using Android.Content;
using Fragment = Android.Support.V4.App.Fragment;
using FragmentManager = Android.Support.V4.App.FragmentManager;
using FragmentTransaction = Android.Support.V4.App.FragmentTransaction;
namespace Xamarin.Forms.Platform.Android.AppCompat
{
internal class MasterDetailContainer : Xamarin.Forms.Platform.Android.MasterDetailContainer, IManageFragments
{
PageContainer _pageContainer;
FragmentManager _fragmentManager;
readonly bool _isMaster;
MasterDetailPage _parent;
Fragment _currentFragment;
bool _disposed;
public MasterDetailContainer(MasterDetailPage parent, bool isMaster, Context context) : base(parent, isMaster, context)
{
Id = FormsAppCompatActivity.GetUniqueId();
_parent = parent;
_isMaster = isMaster;
}
FragmentManager FragmentManager => _fragmentManager ?? (_fragmentManager = ((FormsAppCompatActivity)Context).SupportFragmentManager);
protected override void OnLayout(bool changed, int l, int t, int r, int b)
{
base.OnLayout(changed, l, t, r, b);
// If we're using a PageContainer (i.e., we've wrapped our contents in a Fragment),
// Make sure that it gets laid out
if (_pageContainer != null)
{
if (_isMaster)
{
var controller = (IMasterDetailPageController)_parent;
var width = (int)Context.ToPixels(controller.MasterBounds.Width);
// When the base class computes the size of the Master container, it starts at the top of the
// screen and adds padding (_parent.MasterBounds.Top) to leave room for the status bar
// When this container is laid out, it's already starting from the adjusted y value of the parent,
// so we subtract _parent.MasterBounds.Top from our starting point (to get 0) and add it to the
// bottom (so the master page stretches to the bottom of the screen)
var height = (int)Context.ToPixels(controller.MasterBounds.Height + controller.MasterBounds.Top);
_pageContainer.Layout(0, 0, width, height);
}
else
{
_pageContainer.Layout(l, t, r, b);
}
_pageContainer.Child.UpdateLayout();
}
}
protected override void AddChildView(VisualElement childView)
{
_pageContainer = null;
Page page = childView as NavigationPage ?? (Page)(childView as TabbedPage);
if (page == null)
{
// The thing we're adding is not a NavigationPage or TabbedPage, so we can just use the old AddChildView
if (_currentFragment != null)
{
// But first, if the previous occupant of this container was a fragment, we need to remove it properly
FragmentTransaction transaction = FragmentManager.BeginTransaction();
transaction.DisallowAddToBackStack();
transaction.Remove(_currentFragment);
transaction.SetTransition((int)FragmentTransit.None);
transaction.Commit();
_currentFragment = null;
}
base.AddChildView(childView);
}
else
{
// The renderers for NavigationPage and TabbedPage both host fragments, so they need to be wrapped in a
// FragmentContainer in order to get isolated fragment management
Fragment fragment = FragmentContainer.CreateInstance(page);
var fc = fragment as FragmentContainer;
fc?.SetOnCreateCallback(pc =>
{
_pageContainer = pc;
SetDefaultBackgroundColor(pc.Child);
});
FragmentTransaction transaction = FragmentManager.BeginTransaction();
transaction.DisallowAddToBackStack();
if (_currentFragment != null)
{
transaction.Remove(_currentFragment);
}
transaction.Add(Id, fragment);
transaction.SetTransition((int)FragmentTransit.FragmentOpen);
transaction.Commit();
_currentFragment = fragment;
}
}
protected override void Dispose(bool disposing)
{
if (_disposed)
{
return;
}
_disposed = true;
if (disposing)
{
if (_currentFragment != null)
{
FragmentTransaction transaction = FragmentManager.BeginTransaction();
transaction.DisallowAddToBackStack();
transaction.Remove(_currentFragment);
transaction.SetTransition((int)FragmentTransit.None);
transaction.CommitAllowingStateLoss();
FragmentManager.ExecutePendingTransactions();
_currentFragment = null;
}
_parent = null;
_pageContainer = null;
_fragmentManager = null;
}
base.Dispose(disposing);
}
public void SetFragmentManager(FragmentManager fragmentManager)
{
if (_fragmentManager == null)
_fragmentManager = fragmentManager;
}
}
}
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