#PropertyGrid

PropertyGrid in UIToolbox shows the public fields and properties of Target and edits them. Each row is an editor for the member type. A search box filters the rows. The "A-Z" button changes between category foldouts and one alphabetical list. The panel at the bottom shows the description of the selected row.

<tb:PropertyGrid name="grid" sort-mode="Categorized" show-search="true" show-description="true" />

class Settings
{
    [Category("Text"), Description("The text in the box.")] public string caption = "Hello";
    [Category("Size"), Range(40, 200)] public int width = 120;
    public Color fill = Color.blue;
    public int Edits { get; internal set; }        // no public setter: read-only row
    [DisplayName("Health")] public int MaxHealth { get; set; }
    [Choices(nameof(sizes))] public string Size = "M";        // a dropdown of the texts of sizes()
    public bool Outline;
    [EnabledIf(nameof(Outline))] public float OutlineWidth = 1;
    private string[] sizes() => new[] { "S", "M", "L" };
}

grid.Target = new Settings();
grid.PropertyValueChanged += (item, old, now) => Debug.Log($"{item.Name}: {old} > {now}");
grid.RegisterEditor(typeof(Color), item => myColorPicker(item)); // call item.SetValue(v) to write

• The grid reads the value again after a write, so a setter that clamps shows the clamped value. A write that does not change the value is not recorded.
• Changes to one row within 1 second merge into one undo step, so a slider drag is one step.
• A setter that throws logs the exception and the row shows the old value.
• Members of UnityEngine base classes (for example MonoBehaviour) are left out, unless the target type is itself a UnityEngine type.
• The rows follow the declaration order: base class members first, fields before properties.
• In the UI Builder, a grid without a target edits a sample object in a dashed outline. The sample does not show in Play mode or in a build, and the UI Builder does not save it to the UXML file.
• Nested objects expand up to PropertyGrid.MAX_DEPTH (4) levels. A type that is already in the chain from the target does not expand again, so a cycle stops. .NET types, Unity types, collections and delegates do not expand. The grid keeps the expanded foldouts when it builds the rows again.
• An edit in a nested struct sets the struct copy back in its owner, up the chain. The fields of a read-only struct member are read-only; the members of a read-only class member are not.
• The filter matches the members of the target, not nested members.
• An array or IList<T> member shows in a foldout, "Name (count)". Each element is a row "Element n" with a "-" button, and "+ Add" is under the rows. An element of a class or struct type expands like a nested object. [Range] on the member applies to its elements.
• A list changes in place. An array is replaced by a new array, so a read-only array member does not resize; its elements are still editable, and the move buttons reorder them in place. A read-only list has no buttons and read-only rows. A null collection shows as a text row.
• Undo covers inserts and removes. For those, PropertyValueChanged gives the old and new elements as object[] snapshots.
• The [Range] slider of a long, uint or ulong is a SliderInt when the range fits in an int. Past the int limits it is a long slider: a float Slider to drag and a LongField or UnsignedLongField for the exact value, because a float holds only 24 bits. The grid cuts the range to the type limits (0 for an unsigned type). A value outside the range shows at the nearest end, and an edit writes a value in the range.
• [Range] takes float limits, so a limit past 2^24 is rounded to 7 digits: [Range(0, 1e12f)] gives 1 000 000 000 000.

#Styling