Draw a button in the component header, without frame and background color.

This is useful for icon buttons.

Method which returns an IEnumerator will start a coroutine

Arguments:

• string label = null: label of the button. null means using function name. If starts with $, then a dynamic label will be created to use a field/property/callback as label. Dynamic label when returning null or empty string will hide the button. Rich Label supported.
• string toolTip = null: tool tip for the button.

using SaintsField;
using SaintsField.ComponentHeader;

[HeaderGhostLeftButton("<icon=pencil.png/>")]
public void Edit()
{
}

[HeaderGhostButton("<icon=refresh.png/>", "Play")]
public void Play()
{
}

[HeaderGhostButton("<color=gray><icon=save.png/>", "Pause")]
public void Pause()
{
}

[HeaderGhostButton("<color=gray><icon=trash.png/>", "Resume")]
public void Resume()
{
}

A more complex example of dynamic buttons:

using SaintsField;
using SaintsField.ComponentHeader;

private string _editButtonIcon = "<icon=pencil.png/>";
private bool _editing;

[HeaderGhostButton("
quot; + nameof(_editButtonIcon), "Edit")]
private void StartEdit()
{
    _editing = true;
    _editButtonIcon = "";

    _saveLabel = "<color=brown><icon=save.png/>";
}

[HeaderGhostButton("
quot; + nameof(_saveLabel), "Save")]
private IEnumerator Click()
{
    _editing = false;
    _saveLabel = "<color=gray><icon=save.png/>";
    foreach (int i in Enumerable.Range(0, 200))
    {
        // Debug.Log(
quot;saving {i}");
        yield return null;
    }
    _saveLabel = "<color=lime><icon=check.png/>";
    foreach (int i in Enumerable.Range(0, 200))
    {
        // Debug.Log(
quot;checked {i}");
        yield return null;
    }
    _saveLabel = "";

    _editButtonIcon = "<icon=pencil.png/>";
}

private string _saveLabel = "";

[EnableIf(nameof(_editing)), OnValueChanged(nameof(OnChanged))] public string nickName;
[EnableIf(nameof(_editing)), OnValueChanged(nameof(OnChanged))] public string password;
[EnableIf(nameof(_editing)), OnValueChanged(nameof(OnChanged))] public int age;

private void OnChanged() => _saveLabel = "<color=lime><icon=save.png/>";

It works with ShowInInspector

public interface IMyInterface
{
}

// ... implements...

[OnValueChanged(nameof(ChangeCallback)), ShowInInspector]
public IMyInterface myInterface;

private void ChangeCallback(IMyInterface value)
{
    Debug.Log(value);
}