import com.github.aakira.expandablelayout.ExpandableRelativeLayout; //导入依赖的package包/类
private void findViews() {
    toolbar = (Toolbar) findViewById(R.id.air_toolbar);

    inputTitle = (TextInputEditText) findViewById(R.id.air_inputTitle);
    inputDescription = (TextInputEditText) findViewById(R.id.air_inputDescription);
    textDeviceInfo = (TextView) findViewById(R.id.air_textDeviceInfo);
    buttonDeviceInfo = (ImageButton) findViewById(R.id.air_buttonDeviceInfo);
    layoutDeviceInfo = (ExpandableRelativeLayout) findViewById(R.id.air_layoutDeviceInfo);

    inputUsername = (TextInputEditText) findViewById(R.id.air_inputUsername);
    inputPassword = (TextInputEditText) findViewById(R.id.air_inputPassword);
    inputEmail = (TextInputEditText) findViewById(R.id.air_inputEmail);
    optionUseAccount = (RadioButton) findViewById(R.id.air_optionUseAccount);
    optionAnonymous = (RadioButton) findViewById(R.id.air_optionAnonymous);
    layoutLogin = (ExpandableRelativeLayout) findViewById(R.id.air_layoutLogin);
    layoutAnonymous = (ExpandableRelativeLayout) findViewById(R.id.air_layoutGuest);

    buttonSend = (FloatingActionButton) findViewById(R.id.air_buttonSend);
}
 

import com.github.aakira.expandablelayout.ExpandableRelativeLayout; //导入依赖的package包/类
@CheckedChange({R.id.daily_task_radio, R.id.weekly_task_radio, R.id.disposable_task_radio})
void onCheckedChanged(CompoundButton button) {
    ExpandableRelativeLayout relativeLayout = findExpandableLayoutOf(button);
    if (button.isChecked()) {
        relativeLayout.post(relativeLayout::expand);
    } else {
        relativeLayout.collapse();
    }

}
 

import com.github.aakira.expandablelayout.ExpandableRelativeLayout; //导入依赖的package包/类
private ExpandableRelativeLayout findExpandableLayoutOf(CompoundButton button) {
    ViewGroup parent = (ViewGroup) button.getParent();
    for (int i = 0; i < parent.getChildCount(); i++) {
        if (parent.getChildAt(i) == button) {
            return ((ExpandableRelativeLayout) parent.getChildAt(i + 1));
        }
    }
    throw new IllegalStateException("findExpandableLayout: button = " + button + ", parent = " + parent + ", childCount = " + parent.getChildCount());
}