Android动态添加碎片

import androidx.fragment.app.FragmentActivity;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentTransaction;import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;public class MainActivity extends FragmentActivity { public MainActivity() {
Log.e("TAG", "MainActivity()..");
} @Override
protected void onCreate(Bundle savedInstanceState) {
Log.e("TAG", "MainActivity onCreate()..");
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);//重写onCreate()方法 // 创建Fragment对象
final MyFragment1 fragment1 = new MyFragment1();
// 得到FragmentManager
FragmentManager manager = getSupportFragmentManager();
// 得到FragmentTransacation
FragmentTransaction transaction = manager.beginTransaction();
// 添加Fragment对象并提交
transaction.add(R.id.ll_main, fragment1).commit(); Button button1=(Button)findViewById(R.id.fragment_1);
button1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
showFragment2();
}
});
Button button2=(Button)findViewById(R.id.fragment_2);
button2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
deleteFragment2();
}
}); }
private MyFragment2 fragment2;
public void showFragment2() {
// 创建Fragment对象
fragment2 = new MyFragment2();
// 得到FragmentManager
FragmentManager manager = getSupportFragmentManager();
// 得到FragmentTransacation
FragmentTransaction transaction = manager.beginTransaction(); //将当前操作添加到回退栈, 这样点击back回到上一个状态
transaction.addToBackStack(null); // 替换Fragment对象并提交
transaction.replace(R.id.ll_main, fragment2).commit();
}
public void deleteFragment2() { // 得到FragmentManager
FragmentManager manager = getSupportFragmentManager();
// 得到FragmentTransacation
FragmentTransaction transaction = manager.beginTransaction();
// 移除Fragment对象并提交
transaction.remove(fragment2).commit();
}
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
tools:context=".MainActivity">
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<Button android:id="@+id/fragment_1"
android:text="切换至第二个碎片"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="wrap_content" />
<Button
android:id="@+id/fragment_2"
android:text="删除第二个碎片"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="wrap_content" />
</LinearLayout>
<LinearLayout
android:id="@+id/ll_main"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"></LinearLayout>
</LinearLayout>

import android.os.Bundle;import androidx.fragment.app.Fragment;import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;public class MyFragment1 extends Fragment { public MyFragment1() {
// Required empty public constructor
} @Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState); } @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_my_fragment1, container,false);
}}

import android.os.Bundle;import androidx.fragment.app.Fragment;import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;public class MyFragment2 extends Fragment {
public MyFragment2() {
// Required empty public constructor
} @Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState); } @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_my_fragment2, container,false);
}}

<?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"
tools:context=".MyFragment1"> <!-- TODO: Update blank fragment layout -->
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="这是第一个碎片" /></FrameLayout>

<?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"
tools:context=".MyFragment2"> <!-- TODO: Update blank fragment layout -->
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="这是第二个碎片" /></FrameLayout>