Design material properties do not appear in API 19 appliance

Question

I added the support library for Apis below 21 and am testing the property elevation in my components.

In the layout view, when I click on the design tab, I can see the elevation but when I run to my smartphone nothing changes, everything continues without any elevation.

Before adding support I couldn’t even use the property, so I don’t understand how now I can use and it doesn’t work.

I added the lines in dependencies, in Gradle:

compile 'com.android.support:appcompat-v7:22.2.1'
compile 'com.android.support:design:22.2.1'

Answer 1

With regard to the "Material Design" not everything is supported by appcompat.

In the case of elevation, it is only partially implemented.

To appcompat allows the use of the property, but it is not rendered in lower versions than API21.
The method setElevation(), class android.support.v4.view.Viewcompat, is implemented as follows (with nothing inside):

@Override
public void setElevation(View view, float elevation) {

}

Thus, the code is compatible with the lower versions, but the effect of the Elevation is only visible on Android devices with API21 or higher.
The method is rewritten in implementation concerning API21 thus:

@Override
public void setElevation(View view, float elevation) {

    ViewCompatApi21.setElevation(view, elevation);

}