FragmentTransaction类型的方法add（int，Fragment）不适用于参数（int，WeatherFragment）

Question

I have error in fragment:

"The method replace(int, Fragment) in the type Fragment Transaction is not applicable for the arguments (int, Fragment)"

What should I do? My fragment doesn't appear.

    package com.example.weather;

    import android.support.v7.app.ActionBarActivity;

    import android.support.v4.app.Fragment;

    import android.text.InputType;
    import android.app.AlertDialog;

    import android.content.DialogInterface;

    import android.os.Bundle;

    import android.view.LayoutInflater;

    import android.view.Menu;

    import android.view.MenuItem;

    import android.view.View;

    import android.view.ViewGroup;

    import android.widget.EditText;

    import android.os.Build;

    public class WeatherActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_weather);
        if (savedInstanceState == null) {
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.container, new WeatherFragment())
                    .commit();
        }
    }


    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        if(item.getItemId() == R.id.change_city){
            showInputDialog();
        }
        return false;
    }

    private void showInputDialog(){
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("Change city");
        final EditText input = new EditText(this);
        input.setInputType(InputType.TYPE_CLASS_TEXT);
        builder.setView(input);
        builder.setPositiveButton("Go", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                changeCity(input.getText().toString());
            }
        });
        builder.show();
    }

    public void changeCity(String city){
        WeatherFragment wf = (WeatherFragment) getFragmentManager()
                .findFragmentById(R.id.container);
        wf.changeCity(city);
        new CityPreference(this).setCity(city);
    }
}

Answer 1

The import of fragment should be changed. This is wrong:-

import android.support.v4.app.Fragment;

Correct import is:-

import android.app.Fragment;

Answer 2

I had the same issue and I solve it when I realized that:

WebViewFragment is subclass of android.app.Fragment , so you can't add it using android.support.v4.app.FragmentManager . you must use android.app.FragmentManager

SO I do the following steps to be able to use WebViewFragment

1. I change the superclass of my Fragments to android.app.Fragment instead of android.support.v4.app.Fragment
2. I changed the FragmentManager to android.app.FragmentManager instead of android.support.v4.app.FragmentManager
3. I use getFragmentManager() instead of getSupportFragmentManager

I hope that would be helpful.

Answer 3

Well whatever WeatherFragment is, it is not of the Fragment type and no constructor exists which can handle a WeatherFragment. Maybe you can cast it to Fragment. Cant tell without knowing what it is.

Early morning blunder. The first part of the answer stands ;) He is using his own class WeatherFragment . Without being able to see this, I assume it isn't a (proper) fragment.