在单个活动中动态实现多个片段

android java xml android-fragments

2022-09-01 03:58:29

我正在研究片段

我试图实现的用例：：

我正在使用动态片段
我在单个活动中使用三个片段
我的目标是在所有三个片段之间进行交流
我正在使用片段支持包

每个片段都有一个小部件

my_fragment1有edittext
my_fragment2有button
my_fragment3有TextView

单击文本时，必须显示在`buttonedittexttextview`

到目前为止，我尝试过什么，我已经构建了以下大部分场景

Top_Fragment.java

public class Top_Fragment extends Fragment{

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        // TODO Auto-generated method stub

        View view=inflater.inflate(R.layout.my_fragment1, container, false);

        return view;
    }
}

Middle_Fragment.java

package com.example.deleteme;

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;

public class Middle_Fragment extends Fragment{

    View view;
    Button btn;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        // TODO Auto-generated method stub

        view=inflater.inflate(R.layout.my_fragment2, container, false);
        btn=(Button) view.findViewById(R.id.button1);
        btn.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub



            }
        });
        return view;
    }
}

Bottom_Fragment.java

public class Bottom_Fragment extends Fragment{

    View view;
    TextView display_text;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        view=inflater.inflate(R.layout.my_fragment3, container,false);
        display_text=(TextView) view.findViewById(R.id.editText1);
        return view;
    }

    public void setName(String Name){
        display_text.setText("Result::" + Name);
    }



}

主要活动.java

public class MainActivity extends FragmentActivity {

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

        Top_Fragment frg=new Top_Fragment();//create the fragment instance for the top fragment
        Middle_Fragment frg1=new Middle_Fragment();//create the fragment instance for the middle fragment
        Bottom_Fragment frg2=new Bottom_Fragment();//create the fragment instance for the bottom fragment

        FragmentManager manager=getSupportFragmentManager();//create an instance of fragment manager

        FragmentTransaction transaction=manager.beginTransaction();//create an instance of Fragment-transaction

        transaction.add(R.id.My_Container_1_ID, frg, "Frag_Top_tag");
        transaction.add(R.id.My_Container_2_ID, frg1, "Frag_Middle_tag");
        transaction.add(R.id.My_Container_3_ID, frg2, "Frag_Bottom_tag");


        transaction.commit();

    }


}

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    tools:context=".MainActivity" 
    android:background="@color/black">

    <FrameLayout
        android:id="@+id/My_Container_1_ID"
        android:layout_width="fill_parent"
        android:layout_height="150dp" 
        android:background="@color/yellow">
    </FrameLayout>

    <FrameLayout
        android:id="@+id/My_Container_2_ID"
        android:layout_width="fill_parent"
        android:layout_height="150dp"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/My_Container_1_ID"
        android:background="@color/Orange" >
    </FrameLayout>

    <FrameLayout
        android:id="@+id/My_Container_3_ID"
        android:layout_width="fill_parent"
        android:layout_height="150dp"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/My_Container_2_ID"
        android:background="@color/purple" >
    </FrameLayout>

</RelativeLayout>

my_fragment1.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@color/green" >

    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:ems="10"
        android:textColor="#000000"
        android:singleLine="true" >

        <requestFocus />
    </EditText>

</RelativeLayout>

my_fragment2.xml

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

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:background="@color/black"
        android:text="Button"
        android:textColor="#FFFFFF" />

</RelativeLayout>

my_fragment3.xml

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

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:text="TextView"
        android:textColor="#000000"
        android:textSize="30dp" />

</RelativeLayout>

我的输出如下 ：：

enter image description here

我在实现时遇到的问题：：

我无法将从获得的值设置为单击edit texttextviewbutton

有什么想法吗？

答案 1

所有片段到片段的通信都是通过关联的活动完成的。两个片段永远不应该直接通信。

http://developer.android.com/training/basics/fragments/communicating.html

test.java在你的情况下，MainActivity

public class test extends FragmentActivity implements textEntered {

    String value;
    boolean check = false;
    BottomFragment frg2;
    FragmentTransaction transaction;

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

        Top_Fragment frg = new Top_Fragment();
        frg2 = new BottomFragment();

        FragmentManager manager = getSupportFragmentManager();
        transaction = manager.beginTransaction();
        transaction.add(R.id.My_Container_1_ID, frg, "Frag_Top_tag");
        transaction.add(R.id.My_Container_3_ID, frg2, "Frag_Bottom_tag");
        transaction.commit();
    }

    @Override
    public void setValue(String editextvalue) {
        value = editextvalue;
        if (frg2 != null) {
            frg2.setName(value);
        } else {
            Toast.makeText(getApplicationContext(), "fragment 2  is null", 1000).show();
        }
    }

}

Top_Fragment.java

public class Top_Fragment extends Fragment {
    textEntered mCallback;
    Button b;
    EditText ed;

    public interface textEntered {
        public void setValue(String editextvalue);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
        // TODO Auto-generated method stub

        View view = inflater.inflate(R.layout.my_fragment1, container, false);
        ed = (EditText) view.findViewById(R.id.editText1);


        return view;
    }

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onActivityCreated(savedInstanceState);
        b = (Button) getView().findViewById(R.id.button1);
        b.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                String s = ed.getText().toString();
                mCallback.setValue(s);
            }

        });
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);

        // This makes sure that the container activity has implemented
        // the callback interface. If not, it throws an exception
        try {
            mCallback = (textEntered) activity;
        } catch (ClassCastException e) {
            throw new ClassCastException(activity.toString() +
                " must implement textEntered");
        }
    }
}

my_fragment1.xml

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

    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:ems="10"
        android:textColor="#000000"
        android:singleLine="true" >

        <requestFocus />
    </EditText>

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editText1"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="20dp"
        android:text="Button" />

</RelativeLayout>

更改为

 display_text=(TextView) view.findViewById(R.id.textView1);
 // id is textView 1 not editText1

在底部碎片

折

enter image description here

答案 2

片段之间的通信

在很多情况下，片段之间可能需要通信。您需要在按钮单击事件的片段之间传递数据。您也可以使用 Android 工具栏在片段之间切换。向工具栏添加按钮时，需要使用片段动态更改屏幕。

创建一个界面，这将有助于我们进行沟通

沟通.java

package com.example.amaanmemon.testfragment;

interface Communicate {
 public void sendData();
}

TopFragment.java

package com.example.amaanmemon.testfragment;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;

public class TopFragment extends Fragment {

EditText  firstName;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // TODO Auto-generated method stub

    View view=inflater.inflate(R.layout.my_fragment1, container, false);
    return view;
}

public void onActivityCreated(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onActivityCreated(savedInstanceState);
    firstName = (EditText) getActivity().findViewById(R.id.editText1);
}

public String getData(){
    return firstName.getText().toString();
}
}

中间碎片.java

package com.example.amaanmemon.testfragment;

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;

public class MiddleFragment extends Fragment implements OnClickListener{

View view;
Button btn;
Communicate cm;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    view=inflater.inflate(R.layout.my_fragment2, container, false);
    return  view;
}

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onActivityCreated(savedInstanceState);
    cm = (Communicate) getActivity();
    btn = (Button) getActivity().findViewById(R.id.button1);
    btn.setOnClickListener(this);
}

@Override
public void onClick(View arg0) {
    // TODO Auto-generated method stub
    cm.sendData();
}
}

底部碎屑.java

package com.example.amaanmemon.testfragment;

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;

public class BottomFragment extends Fragment{

int count;
View view;
TextView display_text;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    view=inflater.inflate(R.layout.my_fragment3, container,false);
    return view;
}

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onActivityCreated(savedInstanceState);
    display_text = (TextView)getActivity().findViewById(R.id.textView1);
}

public void incrementData(String displayText){
    display_text.setText(displayText);
}
}

主要活动.java

package com.example.amaanmemon.testfragment;

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

public class MainActivity extends FragmentActivity implements Communicate{

TopFragment frg;
MiddleFragment frg1;
BottomFragment frg2;
FragmentTransaction transaction;

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

    frg = new TopFragment();
    frg1 = new MiddleFragment();
    frg2 = new BottomFragment();

    FragmentManager manager=getSupportFragmentManager();
    transaction=manager.beginTransaction();
    transaction.add(R.id.My_Container_1_ID, frg, "Frag_Top_tag");
    transaction.add(R.id.My_Container_2_ID, frg1, "Frag_Middle_tag");
    transaction.add(R.id.My_Container_3_ID, frg2, "Frag_Bottom_tag");
    transaction.commit();
}

@Override
public void sendData() {
    String temp = frg.getData();
    frg2.incrementData(temp);
}
}

您可以从问题中复制 xml 文件。您可以观看下面的输出。