在UI中动态更新Fragment中的控件监听，显示等
在开发中有时候会遇见一些的情况：根据不同的需求切换不同的fragment ,然后一些操作使当前fragment中显示的内容进行一些调整。很多时候我们都是想的在fragment添加到Activity中时通过 fragmet. getView()获取fragment对象的View 。然后用findViewById()获取到fragment中的控件对象进行操作，很悲剧的是不管用啊有木有。我是个小白，研究了近一周都没搞定，只有采用另一种方式对fragment中的控件进行操作了。
一. 发送广播更新UI
UI中需要时发送一条广播 可顺便传入一些需要的值，在fragment中接收广播，获取值并对fragment中的控件进行操作，经本人验证完全可以。以下是Demo关键代码
在Fragment中
public class GasFragment extends Fragment {
private TextView gasName;
private TextView gasadderss;
private ReceiveBroadCast receiveBroadCast;
public GasFragment (){}
@Override
public void onAttach(Activity activity) {
/** 注册广播 */
receiveBroadCast = new ReceiveBroadCast();
IntentFilter filter = new IntentFilter();
filter.addAction("com.gasFragment"); //只有持有相同的action的接受者才能接收此广播
activity.registerReceiver(receiveBroadCast, filter);
super.onAttach(activity);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view=inflater.inflate(R.layout.fragment_gas, null);
gasName = (TextView) view.findViewById(R.id.frag_tv_gasname);
gasadderss = (TextView) view.findViewById(R.id.fraggas_tv_adderss);
}
});
return view;
}
class ReceiveBroadCast extends BroadcastReceiver
{
@Override
public void onReceive(Context context, Intent intent)
{
//得到广播中得到的数据，并显示出来
String gasname = intent.getExtras().getString("gasName");
String address = intent.getExtras().getString("address");
gasadderss.setText("地址：\n "+address);
gasName.setText(gasname);
}
}
/**
*注销广播
* */
@Override
public void onDestroyView() {
getActivity().unregisterReceiver(receiveBroadCast);
super.onDestroyView();
}
}
在UI中
public class MainPage extends FragmentActivity {
private GasFragment gasFragment; //加油站的fragment
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_page);
gasFragment = new GasFragment();
FragmentManager fm = getSupportFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.replace(R.id.main_fl_fragment, couponFragment);// 将帧布局替换成Fragment
ft.commit();// 提交
Intent intent = new Intent(); // Itent就是我们要发送的内容
intent.setAction("com.gasFragment"); // 设置你这个广播的action
intent.putExtra("gasName","核反应能量加油站");
intent.putExtra("address", "太平洋街11号");
sendBroadcast(intent); // 发送广播
}
}
对应xml就不用上传了吧，很简单的布局。这样就可以动态的更新fragment中的显示内容了。
二. 通过Handler刷新Fragment
在需要交互的Activity中建立Handler对象 具体上代码
public class MainActivity extends FragmentActivity implements OnClickListener{
FrameLayout fl_replace;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
fragmentA = new FragmentA();
fragmentA.setHandler(handler);
fl_replace=(FrameLayout) findViewById(R.id.fl_replace);
findViewById(R.id.btn_replace).setOnClickListener(this);
findViewById(R.id.btn_refresh).setOnClickListener(this);
findViewById(R.id.btn_return).setOnClickListener(this);
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn_replace:
fl_replace.setVisibility(View.VISIBLE);
FragmentManager fm=getSupportFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.replace(R.id.fl_replace, fragmentA);
ft.commit();
break;
case R.id.btn_refresh:
handler.sendEmptyMessage(FragmentA.ACT_REF);
break;
case R.id.btn_return:
fl_replace.setVisibility(View.GONE);
break;
}
}
Handler handler =new Handler(){
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case FragmentA.ACT_REF:// 在Activity中刷新Fragment
fragmentA.setTextStr("on Activity refresh ");
break;
case FragmentA.FRAG_REF://在Fragment中刷新Fragment
fragmentA.setTextStr("on Fragment refresh ");
break;
}
};
};
private FragmentA fragmentA;
}在Fragment 中获取Handler 并通过此对象发消息 代码如下
public class FragmentA extends Fragment{
public static final int FRAG_REF=0;//on Fragment refresh Fragment
public static final int ACT_REF=1;//on Activity refresh Fragment
private TextView tv;
public FragmentA(){}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view=inflater.inflate(R.layout.frag_a, null);
tv = (TextView) view.findViewById(R.id.fragment_tv);
view.findViewById(R.id.fragment_btn).setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
handler.sendEmptyMessage(FRAG_REF);
}
});
return view;
}
Handler handler;
public void setHandler(Handler handler){
this.handler =handler;
}
public void setTextStr(String str){
tv.setText(str);
}
}handler 更新是随后添加的 所以我写了一个Demo 需要的可以去下载，一看就懂了 很简单的 http://download.csdn.net/detail/yangbo437993234/8423493