Fragment
界面的设置和布局
*利用传统布局来规划界面
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:gravity="bottom|center_horizontal"
android:text="@string/bt_1"
android:textColor="#DBD"
android:onClick="onClick"
android:textSize="20dp"
android:id="@+id/show">
</TextView>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Show Next Page"
android:layout_marginLeft="30dp"
android:layout_marginRight="30dp"
android:id="@+id/yes"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
</TextView>
</LinearLayout>
第二个界面的转换
<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.a15083.fragmentandactivity.FirstFragment">
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:color/holo_blue_light"
android:gravity="center"
android:textSize="25sp"
android:text="@string/first_fragment" />
</FrameLayout>
java代码的实现
package com.example.bwqpzy.fragment1;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;
import com.example.bwqpzy.fragment1.FirstFragment;
import com.example.bwqpzy.fragment1.SecondFragment;
public class MainActivity extends AppCompatActivity {
FirstFragment firstFragment;
SecondFragment secondFragment;
private boolean qh = true;
private boolean tc= false;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentManager manager = getFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
firstFragment = new FirstFragment();
transaction.add(R.id.yes,firstFragment);
transaction.commit();
}
public void onClick(View view) {
if(view.getId() == R.id.yes){
tc = true;
if(qh){
FragmentManager manager = getFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
if (secondFragment == null){
secondFragment = new SecondFragment();
transaction.replace(R.id.next,secondFragment);
transaction.commit();
qh = false;
} else{
transaction.replace(R.id.yes,secondFragment);
transaction.commit();
qh = false;
}
}else{
Toast.makeText(this,"This is second fragment",Toast.LENGTH_SHORT).show();
}
}
}
public boolean onKeyDown(int keyCode, KeyEvent event) {
if(event.getKeyCode()== KeyEvent.KEYCODE_BACK&&tc){
FragmentManager manager = getFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
qh = true;
tc = false;
transaction.replace(R.id.yes,firstFragment);
transaction.commit();
return false;
} else {
finish();
}
return super.onKeyDown(keyCode, event);
}
}