【发布时间】：2016-11-13 03:53:28
【问题描述】：
在 Android Studio 2.1.2 中，我尝试使用 Fragment 进行基本活动。无论我看到任何文字，我都无法遵循它。当我创建一个新项目时，它包括 MainActivity.java、MainActivityFragment.java、activity_main.xml、content_main.xml 和 fragment_main.xml。但所有著作都不包含 content_main.xml。
我不断尝试并成功展示其他片段。但布局抛出。第一个片段（fragment_main.xml）不会消失。第二个 Fragment(fragment_sub.xml) 出现在第一个 Fragment 的后面。
我该如何解决？提前感谢您的关心。
这些是我的 java 源代码。
package com.example.john.ho05fragment;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
@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_main, 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);
}
public void clickButtonNext(View view) {
Fragment fragment = new SubActivityFragment();
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace( R.id.fragment, fragment );
fragmentTransaction.commit();
}
public void clickButtonPrevious(View view) {
Fragment fragment = new MainActivityFragment();
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace( R.id.fragment, fragment );
fragmentTransaction.commit();
}
}
package com.example.john.ho05fragment;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
/**
* A placeholder fragment containing a simple view.
*/
public class MainActivityFragment extends Fragment {
public MainActivityFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_main, container, false);
}
}
package com.example.john.ho05fragment;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
/**
* A placeholder fragment containing a simple view.
*/
public class SubActivityFragment extends Fragment {
public SubActivityFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_sub, container, false);
}
}
这些是我的 xml 源代码。
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="com.example.john.ho05fragment.MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="@style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<include layout="@layout/content_main" />
<android.support.design.widget.FloatingActionButton
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="@dimen/fab_margin"
android:src="@android:drawable/ic_dialog_email" />
</android.support.design.widget.CoordinatorLayout>
content_main.xml
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/fragment"
android:name="com.example.john.ho05fragment.MainActivityFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:layout="@layout/fragment_main" />
fragment_main.xml
<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:background="#FF0000"
tools:context="com.example.john.ho05fragment.MainActivityFragment"
tools:showIn="@layout/activity_main">
<Button
android:id="@+id/buttonNext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World! Main!!!"
android:onClick="clickButtonNext"/>
</RelativeLayout>
fragment_sub.xml
<RelativeLayout 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:paddingBottom="16dp"
android:paddingLeft="16dp"
android:paddingRight="16dp"
android:paddingTop="16dp"
android:background="#0000FF"
tools:context="com.example.john.ho05fragment.SubActivityFragment"
tools:showIn="@layout/activity_main">
<Button
android:id="@+id/buttonPrevious"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World! Sub!!!!"
android:onClick="clickButtonPrevious"/>
</RelativeLayout>
【问题讨论】：
标签： android xml layout fragment