参考：
java.lang.IllegalStateException: Fragment already active activity/fragment传值
步骤：
1、【发送方】fragment定义接口，并设置数据 2、activity实现接口，并将数据传给【接收方】fragment 3、【接收方】接受activity发送过来的数据
示例：
FragmentA ：发送方
public class FragmentA extends Fragment {
private EditText et;
private FragmentACallBack fragmentACallBack;
public interface FragmentACallBack {
void setData(String data);
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
fragmentACallBack = (FragmentACallBack) getActivity();
}
@Nullable
@Override
public View
onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.layout_a, container,
false);
et = (EditText) view.findViewById(R.id.et);
Button bt = (Button) view.findViewById(R.id.bt);
bt.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
fragmentACallBack.setData(et.getText().toString());
}
});
return view;
}
}
布局：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#00ff00"
android:gravity="center"
android:orientation="vertical">
<EditText
android:id="@+id/et"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="30sp" />
<Button
android:id="@+id/bt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="发送"
android:textSize="30sp" />
</LinearLayout>
MainActivityII ：中介
public class MainActivityII extends FragmentActivity implements FragmentA.FragmentACallBack {
private FragmentA fragmentA;
private FragmentB fragmentB;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mainii);
fragmentA =
new FragmentA();
fragmentB =
new FragmentB();
getFragmentManager().beginTransaction().replace(R.id.container_a, fragmentA,
"fragmentA").commit();
getFragmentManager().beginTransaction().replace(R.id.container_b, fragmentB,
"fragmentB").commit();
}
@Override
public void setData(String data) {
Bundle bundle =
new Bundle();
bundle.putString(
"data", data);
if (fragmentB !=
null) {
fragmentB =
new FragmentB();
fragmentB.setArguments(bundle);
getFragmentManager().beginTransaction().replace(R.id.container_b, fragmentB,
"fragmentB").commit();
}
}
}
布局：
<?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:orientation="vertical">
<LinearLayout
android:id="@+id/container_a"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="@color/colorAccent"
android:orientation="horizontal" />
<LinearLayout
android:id="@+id/container_b"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="@color/colorPrimary"
android:orientation="horizontal" />
</LinearLayout>
FragmentB ：接收方
public class FragmentB extends Fragment {
private TextView tvb;
@Nullable
@Override
public View
onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
View view = LayoutInflater.from(getActivity()).inflate(R.layout.layout_b, container,
false);
tvb = ((TextView) view.findViewById(R.id.tv_b));
Bundle bundle = getArguments();
if (bundle !=
null) {
String data = bundle.getString(
"data");
tvb.setText(data);
}
return view;
}
}
布局：
<?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:orientation="vertical">
<TextView
android:id="@+id/tv_b"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:text="bbbbbbb"
android:textColor="@color/colorAccent"
android:textSize="25sp" />
</LinearLayout>
