About appium API is missing?

Like

sendKeyEvent、findElementByAndroidUIAutomator、getNetworkConnection()

is change? but i can’t find some document about that
if it is change please tell about the new API, and next question is if i get the parent element i want to get the Children element text. how to get it .

I get it ,it is wrong in the object driver

private AppiumDriver driver;

it is rigth

public AndroidDriver driver;