片段打开layout_activity

Question

hi i have a big problem with this type of programming i cannot open the layout into fragment, this is my code. i need to know what i have to insert into main.java for open the tooldadi.java and toolnomi.java to se the proper layout. thanks a lot this site is the best.

tooldadi.java

 import android.app.Fragment; import android.os.Bundle; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; /** * Created by ferdinandoargenzio on 23/07/15. */ public class tooldadi extends Fragment { @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { //Inflate the layout for this fragment return inflater.inflate( R.layout.tooldadi_layout, container, false); } } 

toolnomi.java

 import android.app.Fragment; import android.os.Bundle; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; /** * Created by ferdinandoargenzio on 23/07/15. */ public class toolnomi extends Fragment { @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { //Inflate the layout for this fragment return inflater.inflate( R.layout.toolnomi_layout, container, false); } } 

tooldadi_layout.xml

 <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="tool dadi" android:id="@+id/textView" android:layout_gravity="center_horizontal" /> </LinearLayout> 

tooldadi_layout.xml

 <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="tool nomi" android:id="@+id/textView2" android:layout_gravity="center_horizontal" /> </LinearLayout> 

Main.java

 import android.app.Activity; import android.content.Intent; import android.support.v7.app.ActionBarActivity; import android.support.v7.app.ActionBar; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.content.Context; import android.os.Build; import android.os.Bundle; import android.view.Gravity; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.support.v4.widget.DrawerLayout; import android.widget.ArrayAdapter; import android.widget.TextView; public class Main extends ActionBarActivity implements NavigationDrawerFragment.NavigationDrawerCallbacks { /** * Fragment managing the behaviors, interactions and presentation of the navigation drawer. */ private NavigationDrawerFragment mNavigationDrawerFragment; /** * Used to store the last screen title. For use in {@link #restoreActionBar()}. */ private CharSequence mTitle; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mNavigationDrawerFragment = (NavigationDrawerFragment) getSupportFragmentManager().findFragmentById(R.id.navigation_drawer); mTitle = getTitle(); // Set up the drawer. mNavigationDrawerFragment.setUp( R.id.navigation_drawer, (DrawerLayout) findViewById(R.id.drawer_layout)); } @Override public void onNavigationDrawerItemSelected(int position) { // update the main content by replacing fragments FragmentManager fragmentManager = getSupportFragmentManager(); fragmentManager.beginTransaction() .replace(R.id.container, PlaceholderFragment.newInstance(position + 1)) .commit(); } public void onSectionAttached(int number) { switch (number) { case 1: mTitle = getString(R.string.title_section1); break; case 2: mTitle = getString(R.string.title_section2); break; case 3: mTitle = getString(R.string.title_section3); break; case 4: mTitle = getString(R.string.title_section4); break; case 5: mTitle = getString(R.string.title_section5); break; case 6: mTitle = getString(R.string.title_section6); break; } } public void restoreActionBar() { ActionBar actionBar = getSupportActionBar(); actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD); actionBar.setDisplayShowTitleEnabled(true); actionBar.setTitle(mTitle); } @Override public boolean onCreateOptionsMenu(Menu menu) { if (!mNavigationDrawerFragment.isDrawerOpen()) { // Only show items in the action bar relevant to this screen // if the drawer is not showing. Otherwise, let the drawer // decide what to show in the action bar. getMenuInflater().inflate(R.menu.main, menu); restoreActionBar(); return true; } return super.onCreateOptionsMenu(menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle action bar item clicks here. The action bar will // automatically handle clicks on the Home/Up button, so long // as you specify a parent activity in AndroidManifest.xml. int id = item.getItemId(); //noinspection SimplifiableIfStatement if (id == R.id.action_settings) { return true; } return super.onOptionsItemSelected(item); } /** * A placeholder fragment containing a simple view. */ public static class PlaceholderFragment extends Fragment { /** * The fragment argument representing the section number for this * fragment. */ private static final String ARG_SECTION_NUMBER = "section_number"; /** * Returns a new instance of this fragment for the given section * number. */ public static PlaceholderFragment newInstance(int sectionNumber) { PlaceholderFragment fragment = new PlaceholderFragment(); Bundle args = new Bundle(); args.putInt(ARG_SECTION_NUMBER, sectionNumber); fragment.setArguments(args); return fragment; } public PlaceholderFragment() { } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.fragment_main, container, false); return rootView; } @Override public void onAttach(Activity activity) { super.onAttach(activity); ((Main) activity).onSectionAttached( getArguments().getInt(ARG_SECTION_NUMBER)); } } } 

Answer 1

I think you are making things complex. And I don't see binding instances of fragments to Main. Make the following changes:

@Override
public void onNavigationDrawerItemSelected(int position) {
    Fragment fragment = null;
    switch (position) {
        case 0:
            fragment = new tooldadi();
            mTitle = getString(R.string.title_section1);
            break;
        case 1:
            fragment = new toolnomi();
            mTitle = getString(R.string.title_section2);
            break;
        case 2:
            mTitle = getString(R.string.title_section3);
            break;
        case 3:
            mTitle = getString(R.string.title_section4);
            break;
        case 4:
            mTitle = getString(R.string.title_section5);
            break;
        case 5:
            mTitle = getString(R.string.title_section6);
            break;
    }
    // update the main content by replacing fragments
    FragmentManager fragmentManager = getSupportFragmentManager();
    fragmentManager.beginTransaction()
            .replace(R.id.container, fragment)
            .commit();
}

However, I would suggest using NewInstance method for individual fragments instead of directly calling new on them to avoid intermittent crashes.