How to Programmatically Set an Attribute

How to programmatically set style attribute in a view

Generally you can't change styles programmatically; you can set the look of a screen, or part of a layout, or individual button in your XML layout using themes or styles. Themes can, however, be applied programmatically.

There is also such a thing as a StateListDrawable which lets you define different drawables for each state the your Button can be in, whether focused, selected, pressed, disabled and so on.

For example, to get your button to change colour when it's pressed, you could define an XML file called res/drawable/my_button.xml directory like this:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
  <item
    android:state_pressed="true"
    android:drawable="@drawable/btn_pressed" />
  <item
    android:state_pressed="false"
    android:drawable="@drawable/btn_normal" />
</selector>

You can then apply this selector to a Button by setting the property android:background="@drawable/my_button".

How to set attribute programmatically

You can try this:

TypedValue typedValue = new TypedValue();
Theme theme = context.getTheme();
theme.resolveAttribute(R.attr.ColorTextNotActive, typedValue, true);
@ColorInt int color = typedValue.data;
et_name.setTextColor(color);

How do you programmatically set an attribute?

setattr(x, attr, 'magic')

For help on it:

>>> help(setattr)
Help on built-in function setattr in module __builtin__:

setattr(...)
    setattr(object, name, value)
    
    Set a named attribute on an object; setattr(x, 'y', v) is equivalent to
    ``x.y = v''.

However, you should note that you can't do that to a "pure" instance of object. But it is likely you have a simple subclass of object where it will work fine. I would strongly urge the O.P. to never make instances of object like that.

Is it possible to programmatically set instance attributes?

I would use **kwargs and setattr:

class Foo(object):

    def load_values(self, **kwargs):
        for key, value in kwargs.iteritems():
            setattr(self, key, value)


foo = Foo()
foo.load_values(egg='bacon', sausages='spam')
# or
foo.load_values(**{'egg': 'bacon', 'sausages': 'spam'})

print(foo.egg) # bacon
print(foo.sausages) # spam

How to set a custom attribute on a view programmatically

It seems that android does not support enum attributes for this kind of work. You must have to work with boolean attributes

<attr name="validation_state_none" format="boolean"/>
<attr name="validation_state_error" format="boolean"/>
...

The most common example of what you trying to do is like focusable, editable attributes. And it's handled with atomic booleans attributes in android source

Another solution that might help you (Not tested) is to create your own drawable programmatically. Take a look at DrawableContainer and StateListDrawable

how to set the Style Attribute Programmatically in Android?

Dynamic style change is not currently supported. You must set the style before the view is create (in xml).

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