Fragment跳转

一、页面布局

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_fragment"
    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:orientation="vertical"
    tools:context="com.example.dell.fragmentapplication.FragmentActivity">

        <LinearLayout
            android:id="@+id/begin"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:orientation="vertical">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:orientation="vertical"
            android:layout_weight="1">
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/diyiduan"
                android:layout_gravity="center"
                android:layout_marginTop="200dp"
                android:textSize="30sp"/>

            <Button
                android:id="@+id/nextpage"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="@string/nextpage"
                android:onClick="onClick"/>

        </LinearLayout>
</LinearLayout>
</LinearLayout>

二、Fragment页面布局

1、 <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"
    android:orientation="vertical"
    tools:context="com.example.dell.fragmentapplication.firstFragment">


        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/diyiduan"
                android:layout_gravity="center"
                android:layout_marginTop="200dp"
                android:textSize="30sp"/>

            <Button
                android:id="@+id/nextpage"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="@string/nextpage"
                android:onClick="onClick"/>

        </LinearLayout>

</FrameLayout>

2、<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="com.example.dell.fragmentapplication.secondFragment">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/dierduan"
            android:layout_gravity="center"
            android:layout_marginTop="200dp"
            android:textSize="30sp"/>

        <Button
            android:id="@+id/nextpage"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:text="@string/nextpage"
            android:onClick="onClick"/>

    </LinearLayout>

</FrameLayout>

三、JAVA功能的具体实现

 package com.example.dell.fragmentapplication;

import android.support.v4.app.Fragment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;

public class FragmentActivity extends AppCompatActivity implements View.OnClickListener {
    private Fragment firstFragment;
    private Fragment secondFragment;
    private boolean skip = true;
    private boolean exit = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fragment);
        firstFragment = new BlankFragment();
        FragmentManager manager = getFragmentManager();
        FragmentTransaction transaction = manager.beginTransaction();
        transaction.add(R.id.begin, firstFragment);
        transaction.commit();
}
    public void onClick(View view) {
    switch (view.getId()) {
        case R.id.nextpage:
            jump();
            break;
    }
}
    private void jump() {
    boolean exit = true;

    if (skip) {
        FragmentManager manager = getFragmentManager();
        FragmentTransaction transaction = manager.beginTransaction();
        if (secondFragment == null) {
             secondFragment = new SecondFragment();
            transaction.replace(R.id.begin, secondFragment);
            transaction.commit();
            skip = false;
        } else {
            transaction.replace(R.id.begin, secondFragment);
            transaction.commit();
            skip = false;
        }
    } else {
        Toast.makeText(this, "This is second fragment", Toast.LENGTH_LONG).show();
    }
}
public boolean onKeyDown(int keyCode, KeyEvent event) {

    if (event.getKeyCode() == KeyEvent.KEYCODE_BACK && exit) {

        FragmentManager manager = getFragmentManager();
        FragmentTransaction transaction = manager.beginTransaction();
        skip = true;
        exit = false;
        transaction.replace(R.id.begin, firstFragment);
        transaction.commit();
        return false;
    } else {
        finish();
    }
    return super.onKeyDown(keyCode, event);


}
}

    package com.example.dell.fragmentapplication;


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



public class secondFragment extends Fragment {


    public secondFragment() {
    }


    @Override

    public class SecondFragment extends Fragment {

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
    View view = inflater.inflate(R.layout.fragment_second,container,false);
    return view;
}
 }