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Activity嵌套多个Fragment实现横竖屏切换

时间:2024-3-2 20:02     作者:韩俊     分类: Android


一、上图

二、需求

近期项目遇到个横竖屏切换的问题,较为复杂,在此记之。

1、Activity中竖屏嵌套3个Fragment,本文简称竖屏FP1,FP2,FP3。

2、其中竖屏FP1与FP2可以切换为横屏的FL1,FL2,即竖屏FP1切换到对应的横屏FL1,竖屏FP2对应切换到横屏FL2。

3、FP3不允许横竖屏切换。

4、竖屏FP1,FP2,FP3用ViewPager实现左右滑动切换。

5、横屏的FL1,FL2用布局中的切换按扭实现左右切换,不允许滑动切换。


看到这需求有点儿晕菜了吧!!!呵呵!!!

(一)先说说我走过的弯路,将横竖屏切换在一个Activity中实现。

(1)、在一个Activity中实现横竖屏切换难在什么地方呢?主要是横竖屏切换,Activity有它自己的生命周期、Fragment也有它的生命周期,而且Activity的生命周期左右着Fragment的生命周期。最复杂的地方是,首次横竖屏切换时,Activity的onDestory()方法会执行,在执行此方法之前,Fragment的onDestoryView()首先会获得执行,接着会执行onCreateView()方法。而首次切换到横屏时,Activity的onCreate()方法会执行,接着横屏FL1的onCreateView()方法又会执行,这样的话,Fragment的布局就会发生覆盖。(这是我在做的时候发现的问题,不知道其他人是否遇到)。

(2)、在一个Activity中横竖屏切换,竖屏布局与横屏布局不一样,本文示例竖屏为Activity中嵌套3个Fragment,横屏嵌套2个Fragment,首先会有很多页面状态需要记录,其次就是Activity与Fragment的生命周期关系问题,确实挺复杂,控制这里面的状态,只有做过的人才知道有多苦。

(二)可取的办法,将横竖屏切换在两个Activity中实现


三、解决问题思路

1、首先当然是要让两个Activity能够横竖切,这里首先需要在AndroidManifest.xml中配置两个Activity能够横竖切换,配置如下:

<activity
            android:name=".ActivityPort"
            android:configChanges="orientation|keyboardHidden|screenSize"
            android:label="@string/app_name"
            android:windowSoftInputMode="stateAlwaysHidden|adjustPan" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

         <activity
            android:name=".ActivityLand"
            android:configChanges="orientation|keyboardHidden|screenSize"
            android:label="@string/app_name"
            android:windowSoftInputMode="stateAlwaysHidden|adjustPan" />

2、竖屏Activity的切换到横屏Activity的时候,通过Intent跳转到横屏的Activity,然后将当前Activity给finish()掉。反之也是一样的逻辑。那么现在面临的一个问题是什么,这个跳转写在什么地方,写在onDestory()方法中显然是不合适的,因为这个方法在横竖切的时候会始终执行,当你在按回退键返回到上一个页面时,同样会执行这个方法,这样跳转的话,就会死循环,会总是打开页面。这时候就想到了Activity的onConfigurationChanged()方法。Google官网说横竖屏切换不希望大家用这个方法实现横竖屏切换,但是遇到了这样怪异的需求,不得不使用。上代码:

 @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        ActivityLand.showActivityLand(this);
        finish();
    }

3、在两个Activity中实现横竖切换之后,换来一个好处,Fragment的生命周期我们非常好控制,里面的逻辑想怎么写就怎么写,而且切换过来之后,布局也会自动去加载横屏的布局。(相信大家明白我的意思)。


4、切换到对应的Fragment,主要是借助于缓存,记录页面状态。详见源码。


5、上主要代码:

(1)竖屏Activity的主要逻辑

package com.example.screenswitch;

import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.content.Intent;
import android.content.pm.ActivityInfo;
import android.content.res.Configuration;
import android.os.Bundle;
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.support.v4.view.ViewPager;
import android.view.KeyEvent;

import com.example.screenswitch.adapter.ChartFragmentPagerAdapter;
import com.example.screenswitch.application.DataCache;
import com.example.screenswitch.fragments.Fragment1;
import com.example.screenswitch.fragments.Fragment2;
import com.example.screenswitch.fragments.Fragment3;

public class ActivityPort extends FragmentActivity {

    private static final String TAG = "ActivityPort";
    /**页面类型-竖屏1**/
    public static final int PORT_PAGE_1 = 1;
    /**页面类型-竖屏2**/
    public static final int PORT_PAGE_2 = 2;
    /**页面类型-竖屏3**/
    public static final int PORT_PAGE_3 = 3;

    private ViewPager vpChartPage;
    private Fragment1 fragment1;
    private Fragment2 fragment2;
    private Fragment3 fragment3;

    /**竖屏FragmentManager**/
    private FragmentManager portfragmentManager;

    /**fragmentTransaction**/
    private FragmentTransaction mFragmentTransaction;

    /**Fragment集合**/
    private List<Fragment> mFragmentList;
    /**分时、K线、明细界面适配器**/
    private ChartFragmentPagerAdapter mPagerAdapter;

    /**屏幕方向 默认指定为竖屏**/
    private int mScreenOrientation = Configuration.ORIENTATION_PORTRAIT;
    /**当前Fragment**/
    private Fragment mCurentFragment;

    public static void showActivityPort(Activity activity){
        Intent intent = new Intent(activity,ActivityPort.class);
        activity.startActivity(intent);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout_main);
        mScreenOrientation = getResources().getConfiguration().orientation;
        portfragmentManager = getSupportFragmentManager();
        mFragmentTransaction = portfragmentManager.beginTransaction();
        switch (mScreenOrientation) {
        case Configuration.ORIENTATION_PORTRAIT:// 竖屏  分时 K线
            findPortViews();
            initPortCtrl();
            break;
        }
    }

    private void findPortViews(){
        vpChartPage = (ViewPager) findViewById(R.id.vp_chart_page);
        vpChartPage.setOnPageChangeListener(new ChartPageChangeListener());
    }

    private void initPortCtrl(){
        fragment1 = new Fragment1();
        fragment2 = new Fragment2();
        fragment3 = new Fragment3();
        mFragmentList = new ArrayList<Fragment>();
        mFragmentList.add(fragment1);
        mFragmentList.add(fragment2);
        mFragmentList.add(fragment3);
        mCurentFragment = fragment1;
        mPagerAdapter = new ChartFragmentPagerAdapter(portfragmentManager,mFragmentList);
        vpChartPage.setAdapter(mPagerAdapter);

        //横1对竖1 横2对竖2  完成对应页的横竖切换
        if(getPageType() == PORT_PAGE_1 || getPageType() == ActivityLand.LAND_PAGE_1){
            setPageType(PORT_PAGE_1);
            vpChartPage.setCurrentItem(0);
        }else if(getPageType() == PORT_PAGE_2 || getPageType() == ActivityLand.LAND_PAGE_2){
            setPageType(PORT_PAGE_2);
            vpChartPage.setCurrentItem(1);
        }
    }

    /**分时、K线、明细竖屏界面切换**/
    class ChartPageChangeListener implements ViewPager.OnPageChangeListener {
        @Override
        public void onPageScrollStateChanged(int i) {

        }

        @Override
        public void onPageScrolled(int i, float v, int i2) {

        }

        @Override
        public void onPageSelected(int i) {
            //设置界面指示器
            switch (i) {
            case 0:
                mCurentFragment = fragment1;
                setPageType(PORT_PAGE_1);
                break;
            case 1:
                setPageType(PORT_PAGE_2);
                mCurentFragment = fragment2;
                setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR);//设置可以横竖切换
                break;
            case 2:
                setPageType(PORT_PAGE_3);
                mCurentFragment = fragment3;
                setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);//禁止屏幕旋转
                break;
            }
        }
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        ActivityLand.showActivityLand(this);
        finish();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if(keyCode == KeyEvent.KEYCODE_BACK){
            finish();
        }
        return true;
    }

    /**记录当前页面类型**/
    private void setPageType(int chartPageType) {
        DataCache.instance().setmChartPageType(chartPageType);
    }

    /**获取当前页面类型 **/
    private int getPageType() {
        return DataCache.instance().getmChartPageType();
    }
}


(2)、横屏Activity的主要逻辑


package com.example.screenswitch;

import android.app.Activity;
import android.content.Intent;
import android.content.res.Configuration;
import android.os.Bundle;
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.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

import com.example.screenswitch.application.DataCache;
import com.example.screenswitch.fragments.Fragment1;
import com.example.screenswitch.fragments.Fragment2;

public class ActivityLand extends FragmentActivity {

    private static final String TAG = "ActivityLand";
    /**页面类型-横屏1**/
    public static final int LAND_PAGE_1 = 4;
    /**页面类型-横屏2**/
    public static final int LAND_PAGE_2 = 5;
    private Fragment1 fragment1;
    private Fragment2 fragment2;

    /**竖屏FragmentManager**/
    private FragmentManager mfragmentManager;

    /**fragmentTransaction**/
    private FragmentTransaction mFragmentTransaction;

    /**屏幕方向 默认指定为竖屏**/
    private int mScreenOrientation = Configuration.ORIENTATION_PORTRAIT;
    /**当前Fragment**/
    private Fragment mCurentFragment;
    /**切换按钮**/
    private Button btSwitch;

    public static void showActivityLand(Activity activity) {
        Intent intent = new Intent(activity, ActivityLand.class);
        activity.startActivity(intent);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout_main);
        mScreenOrientation = getResources().getConfiguration().orientation;
        mfragmentManager = getSupportFragmentManager();
        mFragmentTransaction = mfragmentManager.beginTransaction();

        switch (mScreenOrientation) {
        case Configuration.ORIENTATION_LANDSCAPE:// 横屏  分时 K线
            findLandViews();
            initLandCtrl();
            break;
        }

    }

    private void findLandViews() {
        btSwitch = (Button) findViewById(R.id.bt_switch);
        btSwitch.setOnClickListener(new TheOnSwitchBtnClickListener());
    }

    private void initLandCtrl() {
        fragment1 = new Fragment1();
        fragment2 = new Fragment2();

        //横1对竖1 横2对竖2  完成对应页的横竖切换
        if (getPageType() == ActivityPort.PORT_PAGE_1 || getPageType() == LAND_PAGE_1) {
            setPageType(ActivityPort.PORT_PAGE_1);
            mCurentFragment = fragment1;
        } else if (getPageType() == ActivityPort.PORT_PAGE_2 || getPageType() == LAND_PAGE_2) {
            setPageType(ActivityPort.PORT_PAGE_2);
            mCurentFragment = fragment2;
        }

        mFragmentTransaction = mfragmentManager.beginTransaction();
        mFragmentTransaction.add(R.id.ll_content, mCurentFragment);
        mFragmentTransaction.commit();
    }

    /**
     * 横屏界面切换
     * @author Wilson
     */
    class TheOnSwitchBtnClickListener implements OnClickListener {

        @Override
        public void onClick(View v) {
            if (mCurentFragment instanceof Fragment1) {//横1切到横2
                mCurentFragment = fragment2;
                setPageType(LAND_PAGE_2);
                mFragmentTransaction = mfragmentManager.beginTransaction();
                mFragmentTransaction.replace(R.id.ll_content, fragment2);
                mFragmentTransaction.commit();
            } else if (mCurentFragment instanceof Fragment2) {//横2切到横1
                mCurentFragment = fragment1;
                setPageType(LAND_PAGE_1);
                mFragmentTransaction = mfragmentManager.beginTransaction();
                mFragmentTransaction.replace(R.id.ll_content, fragment1);
                mFragmentTransaction.commit();
            }
        }

    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);

        ActivityPort.showActivityPort(this);
        finish();

    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if (keyCode == KeyEvent.KEYCODE_BACK) {
            finish();
        }
        return true;
    }

    /**记录当前页面类型**/
    private void setPageType(int chartPageType) {
        DataCache.instance().setmChartPageType(chartPageType);
    }

    /**获取当前页面类型 **/
    private int getPageType() {
        return DataCache.instance().getmChartPageType();
    }
}


6、示例代码下载链接地址

http://download.csdn.net/detail/xiogjie_67/8839853































        <p>版权声明:本文为博主原创文章,未经博主允许不得转载。</p>

标签: android

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