Get parent texInputlayout from child textInputEditText

问题

I am implementing a functionality to change the case of textInputlayout Hint text to upper case when the hint floats up and vice versa.

For that I am using OnFocusChangeListener on its child textInputEditText. To make it easy to implement I am implementing View.OnFocusChangeListener on my activity like:

public class LoginActivity extends BaseActivity implements View.OnFocusChangeListener

and overriding the method in the activity like:

@Override
public void onFocusChange(View v, boolean hasFocus) {
    if(findViewById(v.getId()) instanceof TextInputEditText){
        TextInputLayout textInputLayout = (TextInputLayout) findViewById(v.getId()).getParent();
        if(hasFocus){
            textInputLayout.setHint(textInputLayout.getHint().toString().toUpperCase());
        }else{
            textInputLayout.setHint(Utility.modifiedLowerCase(textInputLayout.getHint().toString()));
        }
    }
}

In the above method I am trying to get the view of parent textInputLayout using the line

TextInputLayout textInputLayout = (TextInputLayout) findViewById(v.getId()).getParent();

The above line of code throws a fatal error

java.lang.ClassCastException: android.widget.FrameLayout cannot be cast to android.support.design.widget.TextInputLayout

and it is very obvious because it returns Framelayout which cannot be casted in textInputLayout

And if I use

TextInputLayout textInputLayout = (TextInputLayout) findViewById(v.getId()).getRootView();

it again throws a fatal error because getRootView() returns DecorView which cannot be casted in textInputLayout

My question is how to get parent textInputLayout from child textInputEditText?

Please guide.

回答1:

I solved the problem with the below line of code:

TextInputLayout textInputLayout = (TextInputLayout) findViewById(v.getId()).getParent().getParent();

It returns textInputlayout as required.

回答2:

You can add id in TextInputLayout like this:

<android.support.design.widget.TextInputLayout
    android:id="@+id/nameLayout"
    style="@style/LightInputLayoutNoBox"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="@string/create_contact_account_data_name"
    app:hintTextAppearance="@style/TextSmall.Bold">

    <android.support.design.widget.TextInputEditText
        android:id="@+id/name"
        style="@style/LightInputFieldNoBox"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:drawableEnd="@drawable/ic_book_contacts" />

</android.support.design.widget.TextInputLayout>

And call findViewById to TextInputLayout in activity

来源：https://stackoverflow.com/questions/44883544/get-parent-texinputlayout-from-child-textinputedittext