Question

我正在尝试实现一个简单的TextView-Database-Changer。但这不起作用，我真的尝试了许多不同的种类，即： yourGroupId =（TextView）view.findViewById（R.id.groupid）; yourGroupId.setText（currentGroupID）;

文本不会改变...

我已经尝试过不同的样式，这是我在SO上找到的。没有任何结果。我也尝试了一些手动输入，例如yourGroupId.setText（“ HAI”）;

这是片段帐户

package com.nic.htv;

import android.content.Context;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;

import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;

public class frag_account extends Fragment {

    private Spinner spinner;
    private static final String[] paths = {"item 1", "item 2", "item 3"};
    private DatabaseReference UsersRef;
    private String currentUserID, currentGroupID;

    View view;
    TextView yourGroupId;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment

        view = inflater.inflate(R.layout.fragment_account, container, false);


        currentUserID = FirebaseAuth.getInstance().getCurrentUser().getUid();
        UsersRef = FirebaseDatabase.getInstance().getReference().child("Users").child(currentUserID);

        UsersRef.addValueEventListener(new ValueEventListener() {

            public void onDataChange(DataSnapshot dataSnapshot)
            {
                currentGroupID = dataSnapshot.child("group_1").getValue(String.class);
                //currentGroupID = dataSnapshot.child("group_1").getValue(String.class);
               // dataSnapshot.child("image").getValue().toString();

                yourGroupId = (TextView)view.findViewById(R.id.groupid);
                yourGroupId.setText(""+currentGroupID);

                UserInformation user_i = new UserInformation();
                user_i.setGroupId(currentGroupID);

                list_account_data(user_i);
            }

            public void onCancelled(DatabaseError error)
            {
                // Failed to read value
                Log.w("New Tag", "Failed to read value.", error.toException());
            }


        });


        return inflater.inflate(R.layout.fragment_account, container, false);
    }

    public void list_account_data(UserInformation user_info)
    {
        final String groupId = user_info.getGroupId();
        Log.d("New Tag", "GroupID-Inside list_acc_data is: " + currentGroupID);

        Log.d("New Tag", "Value is: " + groupId);

    }

}

这是帐户XML

<?xml version="1.0" encoding="utf-8"?>
<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"
    android:background="#FFFFFF"
    tools:context=".frag_account">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="20dp"
            android:background="#03A9F4">

            <TextView
                android:id="@+id/header"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Account" />

        </LinearLayout>
        >

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">

            <TextView
                android:id="@+id/appversion"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="App-Version"
                android:textStyle="bold" />

            <TextView
                android:id="@+id/appversionnr"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/app_version"
                android:layout_marginLeft="20dp"
                android:textStyle="bold" />

            <TextView
                android:id="@+id/yourMail"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Deine Email"
                android:textStyle="bold" />

            <TextView
                android:id="@+id/yourmaildb"
                android:layout_width="200dp"
                android:layout_height="wrap_content"
                android:layout_below="@+id/yourMail"
                android:layout_marginLeft="20dp" />

            <TextView
                android:id="@+id/groupselection"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@+id/header"
                android:text="Gruppenauswahl"
                android:textStyle="bold" />

            <TextView
                android:id="@+id/groupid"
                android:text="Gruppen-ID"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@+id/header"
                android:layout_marginLeft="20dp" />
        </LinearLayout>

    </LinearLayout>

</FrameLayout>

Answer 1

在Fragment的onCreateView()中，您正在将布局视图变量创建为“ view”（如下所示），它应该位于返回值中。但是，在此方法块的最后，您将返回一个新的视图实例，例如inflater.inflate(R.layout.fragment_account, container, false)。因此，将这个新实例替换为已经创建的view。

 public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment

    view = inflater.inflate(R.layout.fragment_account, container, false);

    .....rest

    return view; //replace this instead of creating a new view variable using inflater
}

setText由于某种原因未更改TextView的任何内容

1 个答案: