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这个就会个布局，实现跳转都是看同学的。activity的布局 还有两个Fragment的布局掌握了，这个实现跳转不会。

首先是activity的布局

<?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_main"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:gravity="center"

    android:orientation="vertical"

    tools:context="com.example.administrator.tiaozhuan.MainActivity">

    <LinearLayout

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:gravity="center"

        android:orientation="vertical"

        android:id="@+id/show">

    </LinearLayout>

    <Button

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:text="Show nextpage"

        android:layout_gravity="center"

        android:layout_marginTop="20dp"

        android:id="@+id/btnshow"

        android:onClick="onClick"/>

    <LinearLayout

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_marginTop="100dp"

        android:orientation="vertical"

        android:id="@+id/txtshow2">

    </LinearLayout>

</LinearLayout>

fragment需要两个来进行跳转

第一个：

    <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.administrator.tiaozhuan.FirstFragment">

        <TextView

            android:layout_width="match_parent"

            android:layout_height="match_parent"

            android:gravity="center"

            android:text="This is first fragment!"/>

    </FrameLayout>

</FrameLayout>

第二个：

    <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.administrator.tiaozhuan.SecondFragment">

        <TextView

            android:layout_width="match_parent"

            android:layout_height="match_parent"

            android:gravity="center"

            android:text="This is second fragment!"/>

    </FrameLayout>

</FrameLayout>

下面是主界面java代码  这些都是看同学的修改的。。

public class MainActivity 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_main);

    blankFragment = new firstFragment();

    FragmentManager manager = getFragmentManager();

    FragmentTransaction transaction = manager.beginTransaction();

    transaction.add(R.id.main, blankFragment);

    transaction.commit();

}

public void onClick(View view) {

    switch (view.getId()) {

        case R.id.btn_main:

            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.main, secondFragment);

            transaction.commit();

            skip = false;

        } else {

            transaction.replace(R.id.main, 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.main, blankFragment);

        transaction.commit();

        return false;

    } else {

        finish();

    }

    return super.onKeyDown(keyCode, event);

}

}