Android之怎样实现滑动页面切换【Fragment】

时间:2023-03-09 14:47:21
Android之怎样实现滑动页面切换【Fragment】

Fragment 页面切换不能滑动 所以对于listview 能够加入的左右滑动事件 。不会有冲突比如(QQ的好友列表的删除) 

Fragment 和viewpager 的差别 
Viewpager 的事件都须要写在 MainActivity 使得 MainActivity 类很冗余 
Fragment 内部的事件则能够由其内部去处理分成多个类。

便于维护和管理 MainActivity 仅仅起到一个调度的作用 
这里先用Fragment实现非滑动页面切换,了解原理后我会在还有一篇文章使用Fragment+viewPager加上滑动效果

第一步:创建AndroidprojectFragmentPage
这时会自己主动生成一个MainActivity.java
和一个相应的activity_main.xml文件
在layout目录下创建四个xml文件:

tab1.xml

<?

xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/imag1"
android:orientation="vertical" > </LinearLayout>

tab2.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/image2"
android:orientation="vertical" > </LinearLayout>

tab3.xml

<?

xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/image3"
android:orientation="vertical" > </LinearLayout>

bottom.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="45dp"
android:orientation="horizontal" > <TextView
android:id="@+id/text1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1.0"
android:gravity="center"
android:text="标题1"
android:textColor="#000000"
android:textSize="18.0dip" /> <TextView
android:id="@+id/text2"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1.0"
android:gravity="center"
android:text="标题2"
android:textColor="#000000"
android:textSize="18.0dip" /> <TextView
android:id="@+id/text3"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1.0"
android:gravity="center"
android:text="标题3"
android:textColor="#000000"
android:textSize="18.0dip" /> </LinearLayout>

在src下的自己主动生成的包下创建三个java文件:

Fragment1
注意:导入包时一定要导入:import android.support.v4.app.FragmentActivity;

这个包。

这是Android4.0之后才支持的版本号
4.0之前不支持这个包(有另外一个专门的包)

package com.example.fragmentpage;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup; public class Fragment1 extends Fragment {
private View tab1view;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
tab1view=inflater.inflate(R.layout.tab1, container, false);
return tab1view;
} }

Fragment2

package com.example.fragmentpage;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup; public class Fragment2 extends Fragment { private View tabview1;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
tabview1 = inflater.inflate(R.layout.tab2, container,false);
return tabview1;
} }

Fragment3

package com.example.fragmentpage;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup; public class Fragment3 extends Fragment{
private View tab3view ; @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
tab3view = inflater.inflate(R.layout.tab3, container, false);
return tab3view;
} }

第四步:

在MainActivity中写入

package com.example.fragmentpage;
import android.os.Bundle;
import android.app.Activity;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.text.method.HideReturnsTransformationMethod;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.TextView; public class MainActivity extends FragmentActivity implements OnClickListener{
private TextView t1;
private TextView t2;
private TextView t3; private Fragment tab1;
private Fragment tab2;
private Fragment tab3; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_main);
initView();//依据Id索引组件
initEvent();//加入监听
setSelect(0);// }
private void initEvent() {
t1.setOnClickListener(this);
t2.setOnClickListener(this);
t3.setOnClickListener(this);
}
private void initView() {
t1 = (TextView) findViewById(R.id.text1);
t2 = (TextView) findViewById(R.id.text2);
t3 = (TextView) findViewById(R.id.text3); } /*
* 重置textView的内容
* */
private void reset() {
t1.setText("标题1");
t2.setText("标题2");
t3.setText("标题3");
}
private void setSelect(int i) {
// TODO Auto-generated method stub
FragmentManager fm=getSupportFragmentManager();
FragmentTransaction trs = fm.beginTransaction();
//隐藏Fragment
hideFragment(trs);//使所有隐藏
switch(i){
case 0:
if(tab1 == null){
tab1 = new Fragment1();//创建Fragment1的对象(一个页面)
trs.add(R.id.id_content,tab1);
}
else {
trs.show(tab1);//使当前Activity显示tab1即Fragment1页面
}
t1.setText("选中");
break;
case 1:
if(tab2 == null){
tab2 = new Fragment2();
trs.add(R.id.id_content, tab2); }else{
trs.show(tab2);
}
t2.setText("选中");
break;
case 2:
if(tab3 == null){
tab3 = new Fragment3();
trs.add(R.id.id_content, tab3);
}else {
trs.show(tab3);
}
t3.setText("选中");
break;
default:
break;
}
trs.commit(); }
@Override
public void onClick(View v) {//监听事件
// TODO Auto-generated method stub
reset();
switch(v.getId()){
case R.id.text1:
setSelect(0);
break;
case R.id.text2:
setSelect(1); break;
case R.id.text3:
setSelect(2);
break; default:
break; } } private void hideFragment(FragmentTransaction trs) {
// TODO Auto-generated method stub
if(tab1!=null){
trs.hide(tab1); }
if(tab2!=null)
{
trs.hide(tab2);
}
if(tab3!=null)
{
trs.hide(tab3);
} }
}