ContentView2

RedCorners.Forms.ContentView2 is an enhanced version of ContentView. When used inside a ContentPage2, through a recursive chain of events, it gains extra abilities to know when it’s appearing and disappearing on the screen.

This control can also automatically adjust its top and bottom paddings based on the device’s safe insets or custom global values set by the developer. This means taking care of the notch on iPhone X series.

ContentView2 is best used when inside a ContentPage2 page and a BindableModel context attached to it.

Properties

bool FixTopPadding, bool FixBottomPadding

When true, ContentView2 overrides its top and/or bottom components of its Padding property to values retrieved from NotchSystem.Instance.GetPageMargin().

By default, this means you can make sure your UI controls won’t overlap with the iOS notch or the task switching hot area on the bottom of the screen, if you turn on these properties.

On devices without notch, by default the padding values are set to zero.

You can always override or augment these values using the NotchSystem singleton. For more information, read the docs for NotchSystem.

Metadata Properties

ContentView2 provides a number of metadata properties that are meant to be used when the control is embedded inside a tabbed page, or in similar scenarios. These properties are:

• string Title
• ImageSource Icon
• ImageSource SelectedIcon
• bool IsVisibleAsTab
• ICommand ShowTabCommand

For example, if you embed a ContentView2 inside a TabbedContentView:

• The Title property is used as the text for the tab button;
• Icon and SelectedIcon are used as the images for the tab button, depending on whether the tab is active or not. (Note: SelectedIcon is optional.)
• IsVisibleAsTab indicates whether this ContentView2 has a button on the tab bar, or is a hidden page that can only be navigated to programmatically.

Methods

OnStart and OnStop

When ContentView2 controls are embedded inside a ContentPage2, the page recursively finds all instances of ContentView2 objects and calls their OnStart and OnStop methods when:

• They exist in the page and the page appears (OnStart);
• They are added to a page that is already visible (OnStart);
• Their Parent is set to null (OnStop);
• They exist in the page and the page disappears (OnStop).

Overriding these methods can be useful when you want to detect when the control is shown or hidden:

public override void OnStart()
{
    Console.WriteLine("Hello!");
}

public override void OnStop()
{
    Console.WriteLine("Goodbye!");
}

ContentPage2 GetPage()

The GetPage() method recursively seeks and returns the ContentPage2 that holds the ContentView2 control. If no ContentPage2 is found, null is returned.

bool GetIsVisibleRecursive()

This method recursively checks and returns true if the control and all its parent Views are visible (i.e. IsVisible is true).