Android编程心得-FragmentActivity与Fragment两者交互方法简介

在Android4.0后很多时候我们会大量使用到Fragment,Fragment与Activity的交互应该来说是非常重要的，但目前很多实例方法都只介绍了Fragment与Activity交互的方法，没有Activity与Fragment交互的方法，下面我来把解决的思路记录如下。

1.首先我需要定义一个公共接口，用于将Fragment与FragmentActivity中的控件进行交互

public interface IBtnCallListener {
public void transfermsg();
}

2.当fragment中的Button控件需要与FragmentActivity中的Button控件交互时，在Fragment对应的子类中定义

public class LaunchUIFragment extends Fragment implements IBtnCallListener{
IBtnCallListener mbtnListener;
private Button btn_Click;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {

View rootView = inflater.inflate(R.layout.fragment_selection_launch, container, false);
btn_Click=(Button) rootView.findViewById(R.id.bt_click);
btn_Click.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
mbtnListener.transfermsg();
}
});

return rootView;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);

}
@Override
public void onAttach(Activity activity) {
// TODO Auto-generated method stub

try {
mbtnListener=(IBtnCallListener) activity;
} catch (Exception e) {
// TODO: handle exception
throw new ClassCastException(activity.toString() + "must implement mbtnListener");
}

super.onAttach(activity);
}
@Override
public void transfermsg() {
// TODO Auto-generated method stub
System.out.println("由Activity传输过来的信息");
}
}

同时在FragmentActivity中对应相应

public class MainActivity extends FragmentActivity implements IBtnCallListener{

public static final String ARGUMENTS_NAME = "arg";
private RelativeLayout rl_nav;
private SyncHorizontalScrollView mHsv;
private RadioGroup rg_nav_content;
private ImageView iv_nav_indicator;
private ImageView iv_nav_left;
private ImageView iv_nav_right;
private ViewPager mViewPager;
private int indicatorWidth;
public static String[] tabTitle = { "选项1", "选项2", "选项3", "选项4", "选项5" };	//标题
private LayoutInflater mInflater;
private TabFragmentPagerAdapter mAdapter;
private int currentIndicatorLeft = 0;

private Button Btn_Test;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

findViewById();
initView();
setListener();
}
/*
private void setListener() {

mViewPager.setOnPageChangeListener(new OnPageChangeListener() {

@Override
public void onPageSelected(int position) {

if(rg_nav_content!=null && rg_nav_content.getChildCount()>position){
((RadioButton)rg_nav_content.getChildAt(position)).performClick();
}
}

@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {

}

@Override
public void onPageScrollStateChanged(int arg0) {

}
});

rg_nav_content.setOnCheckedChangeListener(new OnCheckedChangeListener() {

@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {

if(rg_nav_content.getChildAt(checkedId)!=null){

TranslateAnimation animation = new TranslateAnimation(
currentIndicatorLeft ,
((RadioButton) rg_nav_content.getChildAt(checkedId)).getLeft(), 0f, 0f);
animation.setInterpolator(new LinearInterpolator());
animation.setDuration(100);
animation.setFillAfter(true);

//执行位移动画
iv_nav_indicator.startAnimation(animation);

mViewPager.setCurrentItem(checkedId);	//ViewPager 跟随一起 切换

//记录当前 下标的距最左侧的 距离
currentIndicatorLeft = ((RadioButton) rg_nav_content.getChildAt(checkedId)).getLeft();

mHsv.smoothScrollTo(
(checkedId > 1 ? ((RadioButton) rg_nav_content.getChildAt(checkedId)).getLeft() : 0) - ((RadioButton) rg_nav_content.getChildAt(2)).getLeft(), 0);
}
}
});
}

private void initView() {

DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);

indicatorWidth = dm.widthPixels / 4;

LayoutParams cursor_Params = iv_nav_indicator.getLayoutParams();
cursor_Params.width = indicatorWidth;// 初始化滑动下标的宽
iv_nav_indicator.setLayoutParams(cursor_Params);

mHsv.setSomeParam(rl_nav, iv_nav_left, iv_nav_right, this);

//获取布局填充器
mInflater = (LayoutInflater)this.getSystemService(LAYOUT_INFLATER_SERVICE);

//另一种方式获取
//		LayoutInflater mInflater = LayoutInflater.from(this);

initNavigationHSV();

mAdapter = new TabFragmentPagerAdapter(getSupportFragmentManager());
mViewPager.setAdapter(mAdapter);

Btn_Test=(Button) findViewById(R.id.btn_test);
Btn_Test.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
mBtnCallListener.transfermsg();
}
});
}
*/
private IBtnCallListener mBtnCallListener;

@Override
public void onAttachFragment(Fragment fragment) {
// TODO Auto-generated method stub

try {
mBtnCallListener=(IBtnCallListener) fragment;
} catch (Exception e) {
// TODO: handle exception
}

super.onAttachFragment(fragment);
}
@Override
public void transfermsg() {
// TODO Auto-generated method stub
System.out.println("由Fragment传输过来的信息");
}

/*
private void initNavigationHSV() {

rg_nav_content.removeAllViews();

for(int i=0;i<tabTitle.length;i++){

RadioButton rb = (RadioButton) mInflater.inflate(R.layout.nav_radiogroup_item, null);
rb.setId(i);
rb.setText(tabTitle[i]);
rb.setLayoutParams(new LayoutParams(indicatorWidth,
LayoutParams.MATCH_PARENT));

rg_nav_content.addView(rb);
}

}

private void findViewById() {

rl_nav = (RelativeLayout) findViewById(R.id.rl_nav);

mHsv = (SyncHorizontalScrollView) findViewById(R.id.mHsv);

rg_nav_content = (RadioGroup) findViewById(R.id.rg_nav_content);

iv_nav_indicator = (ImageView) findViewById(R.id.iv_nav_indicator);
iv_nav_left = (ImageView) findViewById(R.id.iv_nav_left);
iv_nav_right = (ImageView) findViewById(R.id.iv_nav_right);

mViewPager = (ViewPager) findViewById(R.id.mViewPager);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}

public static class TabFragmentPagerAdapter extends FragmentPagerAdapter{

public TabFragmentPagerAdapter(FragmentManager fm) {
super(fm);
}

@Override
public Fragment getItem(int arg0) {
Fragment ft = null;
switch (arg0) {
case 0:
ft = new LaunchUIFragment();
break;

default:
ft = new CommonUIFragment();

Bundle args = new Bundle();
args.putString(ARGUMENTS_NAME, tabTitle[arg0]);
ft.setArguments(args);

break;
}
return ft;
}

@Override
public int getCount() {

return tabTitle.length;
}

}*/

}

其中，主要部分是Fragment需要重写OnAttach方法，将接口对象实例化，同时在Activity要实现对应接口的方法，在该方法中实现你想要的功能，这样就可以由Fragment灵活交互FragmentActivity中的内容与控件了

同理，FragmentActivity想要交互对应的Fragment也需要重写FragmentActivity的OnAttachFragment方法，同时在

Fragment中实现对应接口的方法，在该方法中实现你想要的功能，这样就可以由FragmentActivity灵活交互Fragment中的内容与控件了
(主要看没有注释的部分)

其实，交互的思路都是一样的，全都是通过一个公共的接口调用，在对应的地方实现。