Android中的Fragment-Fragment通信 [英] Fragment-Fragment communication in Android

问题描述

我在 Android 编程方面处于初级水平，因此我需要您真诚的帮助.请任何人帮助我.

I am at beginner level in Android programming, so I need your sincere help for this. Anyone help me please.

我正在尝试使用片段构建一个 SLIDING UI

I am trying to build a SLIDING UI using fragments

所以我的实际怀疑是......我有一个 Fragment(比如 Fragment A)它有一个 TextView 和 Button 和另一个 Fragment(比如 Fragment B).它有一个 TextView .我需要在 Fragment B 的 TextView 中显示 Fragment A 的 TextView 的内容，当我按下FRAGMENT A 中的 Button.我尝试了很多方法，不幸的是我没有得到正确的输出.我相信你们这些人都知道.请帮帮我.

so my actual doubt is ... I have a Fragment (say Fragment A) it has a TextView and Button in it and another Fragment (say Fragment B). It has a TextView in it. I need to show the Fragment A's TextView's content in Fragment B's TextView, when I pressed the Button in FRAGMENT A. I tried many ways, unfortunately I didn't got the proper output. I am sure you peoples know about it. Please help me.

谢谢

推荐答案

监听器应该这样做，所以 Fragment 仍然不相互依赖，可以在一个或两个窗格模式下使用.Activity 应该处理两个片段的侦听器.

It should be done thought listener, so Fragments are still not depend on each other and can be used in one or two pane mode. Activity should handle listeners of both fragments.

这是一个包含两个 Fragment 的活动示例:

Here is an example of activity with two Fragments:

package com.example;

import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;

import com.example.fragment.FragmentA;
import com.example.fragment.FragmentA.TextChangeListener;
import com.example.fragment.FragmentB;

public class ActivityAB extends FragmentActivity {

    FragmentA fragmentA;
    FragmentB fragmentB;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_ab);

        FragmentManager manager = getSupportFragmentManager();
        fragmentA = (FragmentA) manager.findFragmentById(R.id.fragmentA);
        fragmentB = (FragmentB) manager.findFragmentById(R.id.fragmentB);

        fragmentA.setTextChangeListener(new TextChangeListener() {

            @Override
            public void onTextChange(CharSequence newText) {
                fragmentB.updateTextValue(newText);
            }
        });
    }

}

这是片段 A，它具有文本更改事件的自定义侦听器.

Here is Fragment A, that has custom listener for text change event.

package com.example.fragment;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;

import com.example.R;

public class FragmentA extends Fragment {

    TextChangeListener listener;

    public interface TextChangeListener {
        public void onTextChange(CharSequence newText);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_a, container, false);

        Button btn = (Button) view.findViewById(R.id.button1);
        final TextView textView = (TextView) view.findViewById(R.id.textView1);

        btn.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                if (null != listener) {
                    listener.onTextChange(textView.getText());
                }

            }
        });
        return view;
    }

    public void setTextChangeListener(TextChangeListener listener) {
        this.listener = listener;
    }
}

这是具有更新文本字段的公共方法的片段 B:

Here is Fragment B that has public method to update text field:

package com.example.fragment;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import com.example.R;

public class FragmentB extends Fragment {

    TextView textView;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_b, container, false);
        textView = (TextView) view.findViewById(R.id.textView1);
        return view;
    }

    public void updateTextValue(CharSequence newText) {
        textView.setText(newText);
    }
}

ActivityAB xml 布局:

ActivityAB xml Layout:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:baselineAligned="false"
    android:orientation="horizontal" >

    <fragment
        android:id="@+id/fragmentA"
        android:name="com.example.fragment.FragmentA"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1" />

    <fragment
        android:id="@+id/fragmentB"
        android:name="com.example.fragment.FragmentB"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1" />

</LinearLayout>

片段一个 xml 布局:

Fragment A xml layout:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="This is text"
        android:textAppearance="?android:attr/textAppearanceLarge" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Show" />

</LinearLayout>

片段 B xml 布局:

Fragment B xml layout:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="(here will be text)"
        android:textAppearance="?android:attr/textAppearanceLarge" />

</LinearLayout>

这篇关于Android中的Fragment-Fragment通信的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！