void toggleBackButtonText_Clicked(object sender, EventArgs e)
{
var page = Navigation.NavigationStack.First();
var titleText = NavigationPage.GetBackButtonTitle(page);
if (titleText == null)
{
titleText = "Custom Text";
}
else if (titleText == "Custom Text")
{
titleText = "";
}
else
{
titleText = null;
}
NavigationPage.SetBackButtonTitle(page, titleText);
changeTitleView_Clicked(this, EventArgs.Empty);
string result = (titleText == null) ? "<null>" : titleText;
btnToggleBackButtonTitle.Text = $"Toggle Back Button Title Text: {result}";
}
internal void UpdateNavigationItems(bool forceShowBackButton = false)
{
if (_toolbar == null || _navigation == null || _navigationGroup == null)
{
return;
}
var items = new List <ToolbarItem>();
if (ShowBackButton(forceShowBackButton))
{
bool isBackButtonTextSet = _navigation.IsSet(NavigationPage.BackButtonTitleProperty);
var backButtonTitle = isBackButtonTextSet ? NavigationPage.GetBackButtonTitle(_navigation) : GetPreviousPageTitle();
var backButtonItem = new ToolbarItem
{
Text = backButtonTitle,
Command = new Command(async() => await NavigateBackFrombackButton())
};
items.Add(backButtonItem);
}
UpdateGroup(_navigationGroup, items);
var navItemBack = _navigationGroup.Items.FirstOrDefault();
if (navItemBack != null)
{
navItemBack.Button.Image = NSImage.ImageNamed(NSImageName.GoLeftTemplate);
navItemBack.Button.SizeToFit();
UpdateGroupWidth(_navigationGroup);
navItemBack.Button.AccessibilityTitle = "NSBackButton";
}
}
public override void ViewWillAppear(bool animated)
{
base.ViewWillAppear(animated);
var page = Element as BaseContentPage <BaseViewModel>;
if (page == null)
{
return;
}
#region for soft back button
var root = NavigationController.TopViewController;
if (!page.NeedOverrideSoftBackButton)
{
return;
}
var title = NavigationPage.GetBackButtonTitle(Element);
root.NavigationItem.SetLeftBarButtonItem(
new UIBarButtonItem(title, UIBarButtonItemStyle.Plain, (sender, args) =>
{
page.OnSoftBackButtonPressed();
}), true);
#endregion
}
private void Button_Clicked(object sender, System.EventArgs e)
{
var foo = NavigationPage.GetBackButtonTitle(this);
NavigationPage.SetBackButtonTitle(this, "ddd");
//NavigationPage.SetHasNavigationBar(this, false);
}
public override void ViewWillAppear(bool animated)
{
base.ViewWillAppear(animated);
var page = Element as XFVNNavigationAnimationBasePageView;
if (page == null)
{
return;
}
#region for soft back button
var root = NavigationController.TopViewController;
if (!page.NeedOverrideSoftBackButton)
{
return;
}
var title = "<" + (string.IsNullOrEmpty(NavigationPage.GetBackButtonTitle(Element)) ? "Back" : NavigationPage.GetBackButtonTitle(Element));
root.NavigationItem.SetLeftBarButtonItem(
new UIBarButtonItem(title, UIBarButtonItemStyle.Plain, (sender, args) =>
{
page.OnSoftBackButtonPressed();
}), true);
#endregion
}
ParentingViewController CreateViewControllerForPage(Page page)
{
if (Platform.GetRenderer(page) == null)
{
Platform.SetRenderer(page, Platform.CreateRenderer(page));
}
// must pack into container so padding can work
// otherwise the view controller is forced to 0,0
var pack = new ParentingViewController(this)
{
Child = page
};
if (!string.IsNullOrWhiteSpace(page.Title))
{
pack.NavigationItem.Title = page.Title;
}
// First page and we have a master detail to contend with
UpdateLeftBarButtonItem(pack);
//var pack = Platform.GetRenderer (view).ViewController;
var titleIcon = NavigationPage.GetTitleIcon(page);
if (!string.IsNullOrEmpty(titleIcon))
{
try
{
//UIImage ctor throws on file not found if MonoTouch.ObjCRuntime.Class.ThrowOnInitFailure is true;
pack.NavigationItem.TitleView = new UIImageView(new UIImage(titleIcon));
}
catch
{
}
}
var titleText = NavigationPage.GetBackButtonTitle(page);
if (titleText != null)
{
// adding a custom event handler to UIBarButtonItem for navigating back seems to be ignored.
pack.NavigationItem.BackBarButtonItem = new UIBarButtonItem {
Title = titleText, Style = UIBarButtonItemStyle.Plain
};
}
var pageRenderer = Platform.GetRenderer(page);
pack.View.AddSubview(pageRenderer.ViewController.View);
pack.AddChildViewController(pageRenderer.ViewController);
pageRenderer.ViewController.DidMoveToParentViewController(pack);
return(pack);
}
void UpdateBackButtonTitle()
{
string title = null;
if (_previousPage != null)
{
title = NavigationPage.GetBackButtonTitle(_previousPage);
}
_container.BackButtonTitle = title;
}
string GetBackButtonText()
{
if (_navigation == null || _navigation.StackDepth <= 1)
{
return(string.Empty);
}
var page = _navigation.Peek(1);
return(NavigationPage.GetBackButtonTitle(page)
?? page.Title
?? _defaultBackButtonTitle);
}
private void SetPageId(Page page)
{
if (page == null)
{
return;
}
var id = NavigationPage.GetBackButtonTitle(page);
if (string.IsNullOrWhiteSpace(id))
{
NavigationPage.SetBackButtonTitle(page, App.XenClassId);
}
}
public void SetPage(BaseContentPage basePage, BaseContentUI baseContentUI)
{
ViewPage = basePage;
ContentUI = baseContentUI;
Title = ContentUI.Title;
appBarBackBtnTitle = NavigationPage.GetBackButtonTitle(ViewPage);
InitProperty();
ViewPage.Appearing += ViewPage_Appearing;
InitLifecycle();
}
public override void ViewWillAppear(bool animated)
{
base.ViewWillAppear(animated);
if (!(Element is ModalNavigationPage element))
{
return;
}
if (!(element.RootPage is ISoftNavigationPage page))
{
return;
}
var title = $"<{(string.IsNullOrEmpty(NavigationPage.GetBackButtonTitle(Element)) ? BackTitle : NavigationPage.GetBackButtonTitle(Element))}";
TopViewController.NavigationItem.SetLeftBarButtonItem(
new UIBarButtonItem(title, UIBarButtonItemStyle.Plain, (sender, args) =>
{
if (!page.OnSoftBackButtonPressed())
{
element.PopAsync(animated);
}
}), animated);
}
public NavigationBarGallery(NavigationPage rootNavPage)
{
_rootNavPage = rootNavPage;
int toggleBarTextColor = 0;
int toggleBarBackgroundColor = 0;
ToolbarItems.Add(new ToolbarItem {
Text = "Save"
});
NavigationPage.SetTitleIconImageSource(this, "coffee.png");
SearchBar searchBar = new SearchBar {
HeightRequest = 44, WidthRequest = 100
};
// Note: Large and complex controls, such as ListView and TableView, are not recommended.
var controls = new List <View>
{
searchBar,
new ActivityIndicator {
IsRunning = true
},
new BoxView {
BackgroundColor = Colors.Red
},
new Button {
Text = "Button!"
},
new DatePicker {
},
new Editor {
Text = "Editor"
},
new Entry {
Placeholder = "Entry"
},
new Image {
Source = "crimson.jpg", HeightRequest = 44
},
new Label {
Text = "Title View Label!"
},
new Picker {
ItemsSource = Enumerable.Range(0, 10).Select(i => $"Item {i}").ToList(), Title = "Picker"
},
new ProgressBar {
Progress = 50
},
new Slider {
},
new Stepper {
},
new Switch {
},
new TimePicker {
}
};
int idx = 0;
NavigationPage.SetTitleView(this, CreateTitleView(controls[idx]));
rootNavPage.On <Android>().SetBarHeight(450);
rootNavPage.On <iOS>().SetPrefersLargeTitles(false);
Content = new ScrollView
{
Content =
new StackLayout
{
Children =
{
new Button {
Text = "Go to SearchBarTitlePage",
Command = new Command(() => {
rootNavPage.PushAsync(new SearchBarTitlePage(rootNavPage));
})
},
new Button {
Text = "Change BarTextColor",
Command = new Command(() => {
if (toggleBarTextColor % 2 == 0)
{
rootNavPage.BarTextColor = Colors.Teal;
}
else
{
rootNavPage.BarTextColor = null;
}
toggleBarTextColor++;
})
},
new Button {
Text = "Change BarBackgroundColor",
Command = new Command(() => {
if (toggleBarBackgroundColor % 2 == 0)
{
rootNavPage.BarBackgroundColor = Colors.Navy;
}
else
{
rootNavPage.BarBackgroundColor = null;
}
toggleBarBackgroundColor++;
})
},
new Button {
Text = "Change Both to default",
Command = new Command(() => {
rootNavPage.BarTextColor = null;
rootNavPage.BarBackgroundColor = null;
})
},
new Button {
Text = "Black background, white text",
Command = new Command(() => {
rootNavPage.BarTextColor = Colors.White;
rootNavPage.BarBackgroundColor = Colors.Black;
})
},
new Button {
Text = "Toggle TitleIcon",
Command = new Command(() => {
var titleIcon = NavigationPage.GetTitleIconImageSource(this);
if (titleIcon == null)
{
titleIcon = "coffee.png";
}
else
{
titleIcon = null;
}
NavigationPage.SetTitleIconImageSource(this, titleIcon);
})
},
new Button {
Text = "Toggle TitleView",
Command = new Command(() => {
var titleView = NavigationPage.GetTitleView(this);
if (titleView == null)
{
titleView = CreateTitleView(controls[idx]);
}
else
{
titleView = null;
}
NavigationPage.SetTitleView(this, titleView);
})
},
new Button {
Text = "Next TitleView",
Command = new Command(() => {
idx++;
if (idx >= controls.Count)
{
idx = 0;
}
var titleView = CreateTitleView(controls[idx]);
NavigationPage.SetTitleView(this, titleView);
})
},
new Button {
Text = "Toggle Back Title",
Command = new Command(() => {
var backTitle = NavigationPage.GetBackButtonTitle(rootNavPage);
if (backTitle == null)
{
backTitle = "Go back home";
}
else
{
backTitle = null;
}
NavigationPage.SetBackButtonTitle(rootNavPage, backTitle);
})
},
new Button {
Text = "Toggle Toolbar Item",
Command = new Command(() => {
if (ToolbarItems.Count > 0)
{
ToolbarItems.Clear();
}
else
{
ToolbarItems.Add(new ToolbarItem {
Text = "Save"
});
}
})
},
new Button {
Text = "Toggle Title",
Command = new Command(() => {
if (Title == null)
{
Title = "NavigationBar Gallery - Legacy";
}
else
{
Title = null;
}
})
},
new Button {
Text = "Toggle BarHeight",
Command = new Command(() => {
if (rootNavPage.On <Android>().GetBarHeight() == -1)
{
rootNavPage.On <Android>().SetBarHeight(450);
}
else
{
rootNavPage.ClearValue(BarHeightProperty);
}
})
}
}
}
};
}
void UpdateBackButtonTitle()
{
this.Control.BackButtonTitle = NavigationPage.GetBackButtonTitle(Element);
}
protected virtual void UpdateToolbar()
{
ActionBarDrawerToggle toggle = _drawerToggle;
if (Toolbar == null || NavigationStack.Count == 0 || CurrentPage == null || VirtualView == null)
{
return;
}
bool isNavigated = NavigationStack.Count > 1;
Page currentPage = CurrentPage;
_defaultNavigationIcon ??= Toolbar.NavigationIcon;
if (isNavigated)
{
if (NavigationPage.GetHasBackButton(currentPage))
{
Toolbar.NavigationIcon ??= _defaultNavigationIcon;
if (toggle != null)
{
toggle.DrawerIndicatorEnabled = false;
toggle.SyncState();
}
var prevPage = (Page)NavigationStack[NavigationStack.Count - 2];
var backButtonTitle = NavigationPage.GetBackButtonTitle(prevPage);
ImageSource image = NavigationPage.GetTitleIconImageSource(currentPage);
if (!string.IsNullOrEmpty(backButtonTitle))
{
Toolbar.NavigationContentDescription = backButtonTitle;
}
else if (image == null ||
Toolbar.SetNavigationContentDescription(image) == null)
{
Toolbar.SetNavigationContentDescription(Resource.String.nav_app_bar_navigate_up_description);
}
}
else if (toggle != null && _flyoutPage != null)
{
toggle.DrawerIndicatorEnabled = _flyoutPage.ShouldShowToolbarButton();
toggle.SyncState();
}
else
{
Toolbar.NavigationIcon = null;
}
}
else
{
if (toggle != null && _flyoutPage != null)
{
toggle.DrawerIndicatorEnabled = _flyoutPage.ShouldShowToolbarButton();
toggle.SyncState();
Toolbar.SetNavigationContentDescription(Resource.String.nav_app_bar_open_drawer_description);
}
}
Color tintColor = NavigationView.BarBackgroundColor;
if (tintColor == null)
{
Toolbar.BackgroundTintMode = null;
}
else
{
Toolbar.BackgroundTintMode = PorterDuff.Mode.Src;
Toolbar.BackgroundTintList = ColorStateList.ValueOf(tintColor.ToNative());
}
Brush barBackground = NavigationView.BarBackground;
Toolbar.UpdateBackground(barBackground);
Color textColor = NavigationView.BarTextColor;
if (textColor != null)
{
Toolbar.SetTitleTextColor(textColor.ToNative().ToArgb());
}
Color navIconColor = NavigationPage.GetIconColor(CurrentPage);
if (navIconColor != null && Toolbar.NavigationIcon != null)
{
DrawableExtensions.SetColorFilter(Toolbar.NavigationIcon, navIconColor, FilterMode.SrcAtop);
}
Toolbar.Title = currentPage?.Title ?? string.Empty;
if (Toolbar.NavigationIcon != null && textColor != null)
{
var icon = this.Toolbar.NavigationIcon as DrawerArrowDrawable;
if (icon != null)
{
icon.Color = textColor.ToNative().ToArgb();
}
}
UpdateTitleIcon();
UpdateTitleView();
UpdateToolbarVisibility();
}
