我已经使用'developer.android.com'教程学习了android应用开发两天了。目前,我正在学习片段和框架集的概念。我已经使用片段编写了一个hello world程序。但是问题是我的片段布局两次插入到片段容器中,结果是框架集中有2个重叠的片段。你能告诉我为什么会这样吗,我的代码有什么问题吗?

以下是我的Home_page.java(包含fragment_container的活动)

package com.technology.computer.mit.ctechmit;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;


public class Home_page extends ActionBarActivity {

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



        // Create a new Fragment to be placed in the activity layout
        Home_pageFragment firstFragment = new Home_pageFragment();
        // In case this activity was started with special instructions from an
        // Intent, pass the Intent's extras to the fragment as arguments
        firstFragment.setArguments(getIntent().getExtras());
        // Add the fragment to the 'fragment_container' FrameLayout
        getSupportFragmentManager().beginTransaction()
                .add(R.id.fragment_container, firstFragment).commit();


    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_home_page, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}


下面是我的Home_pageFragment.java(应该插入容器的片段)

package com.technology.computer.mit.ctechmit;

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


/**
 * A placeholder fragment containing a simple view.
 */
public class Home_pageFragment extends Fragment {


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {

        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_home_page, container, false);
    }

}


以下是我的activity_home_page.xml(fragment_container布局)

<fragment
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/fragment_container"
    android:name="com.technology.computer.mit.ctechmit.Home_pageFragment"
    tools:layout="@layout/fragment_home_page"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />


以下是我的fragment_home_page.xml(片段布局)

<LinearLayout
    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:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:orientation="horizontal"
    tools:context=".Home_pageFragment">

    <TextView
        android:text="@string/hello_world"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/button_send" />

</LinearLayout>


您能帮我解决这个错误吗?
为什么片段在家庭活动中被加载两次?
我收到了重叠的Hello World文字。

最佳答案

这很简单。您要插入片段的布局不是用作容器的视图。实际上,它本身就是碎片。

因此,要么将FrameLayout用作片段容器,要么将片段保留在XML中,并且不要调用片段管理器来插入该片段。我建议第一个。

<FrameLayout
   android:id="@+id/fragment_container"
   android:layout_width="match_parent"
   android:layout_height="match_parent"/>

10-07 22:26