Question

我想根据点击的toolbar更改热门fragment，但似乎对我不起作用。我想要的是当我点击fragment时，顶部工具栏应该更改。例如，添加Add按钮并更改Create Fragment的工具栏标题。

Fragment.java

import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        setHasOptionsMenu(true);
        View v = inflater.inflate(R.layout.fragment_event_created, container, false);
        Toolbar toolbar123 = (Toolbar) v.findViewById(R.id.toolbar123);
        ((AppCompatActivity)getActivity()).setSupportActionBar(toolbar123);
        //((MainActivity) getActivity()).getSupportActionBar().hide();
        return v;
    }

片段XML

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.rick.check_in.ui.EventCreatedFragment">

<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/toolbar123"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="#131313"
    android:minHeight="?attr/actionBarSize">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="right"
        android:background="#00aaaaaa">

        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:background="#000"
            android:text="Delete"
            android:textColor="#fff"
            android:textSize="16dp" />

    </LinearLayout>


</android.support.v7.widget.Toolbar>
<!-- TODO: Update blank fragment layout -->
<TextView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="@string/hello_blank_fragment" />

</FrameLayout>

Answer 1

你可以这样做。一旦片段与其活动相关联，就会调用onAttach(Activity)。

public class YourFragment extends Fragment {


    private MainActivity mainActivity;
    private Toolbar toolbar123;


    public YourFragment() {
        // Required empty public constructor
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        mainActivity = (MainActivity)activity;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View v =  inflater.inflate(R.layout.fragment_event_created, container, false);
        toolbar123 = (Toolbar)v.findViewById(R.id.toolbar123);
        setupToolbar();
        return v;
    }

    private void setupToolbar(){
        toolbar123.setTitle(getString("Your Fragment Title"));
        mainActivity.setSupportActionBar(toolbar123);
    }

}

根据片段更改工具栏

1 个答案: