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Currently I have connected activities handled this way, Activity A --> Activity B--Activity C. I discovered that I could use nested fragments and contained in one Activity. So I imagined that would be, 

Main Activity
--Fragment A -> Fragment B -> Fragment C

From this code below, I manage to dynamically populate a text for every created fragments. I am just curious on how I could create fragments and use the flow above with different views.

So my possible resolve is to use if statements in one onCreateView to check if which fragment to be displayed. Your thoughts will help me understand the complex concept of dynamic creation of fragments. Thanks

    public class CollectionDemoActivity extends FragmentActivity {

    /**
     * The {@link android.support.v4.view.PagerAdapter} that will provide fragments representing
     * each object in a collection. We use a {@link android.support.v4.app.FragmentStatePagerAdapter}
     * derivative, which will destroy and re-create fragments as needed, saving and restoring their
     * state in the process. This is important to conserve memory and is a best practice when
     * allowing navigation between objects in a potentially large collection.
     */
    DemoCollectionPagerAdapter mDemoCollectionPagerAdapter;

    /**
     * The {@link android.support.v4.view.ViewPager} that will display the object collection.
     */
    ViewPager mViewPager;

    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_collection_demo);

        // Create an adapter that when requested, will return a fragment representing an object in
        // the collection.
        // 
        // ViewPager and its adapters use support library fragments, so we must use
        // getSupportFragmentManager.
        mDemoCollectionPagerAdapter = new DemoCollectionPagerAdapter(getSupportFragmentManager());

        // Set up action bar.
        final ActionBar actionBar = getActionBar();

        // Specify that the Home button should show an "Up" caret, indicating that touching the
        // button will take the user one step up in the application's hierarchy.
        actionBar.setDisplayHomeAsUpEnabled(true);

        // Set up the ViewPager, attaching the adapter.
        mViewPager = (ViewPager) findViewById(R.id.pager);
        mViewPager.setAdapter(mDemoCollectionPagerAdapter);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                // This is called when the Home (Up) button is pressed in the action bar.
                // Create a simple intent that starts the hierarchical parent activity and
                // use NavUtils in the Support Package to ensure proper handling of Up.
                Intent upIntent = new Intent(this, MainActivity.class);
                if (NavUtils.shouldUpRecreateTask(this, upIntent)) {
                    // This activity is not part of the application's task, so create a new task
                    // with a synthesized back stack.
                    TaskStackBuilder.from(this)
                            // If there are ancestor activities, they should be added here.
                            .addNextIntent(upIntent)
                            .startActivities();
                    finish();
                } else {
                    // This activity is part of the application's task, so simply
                    // navigate up to the hierarchical parent activity.
                    NavUtils.navigateUpTo(this, upIntent);
                }
                return true;
        }
        return super.onOptionsItemSelected(item);
    }

    /**
     * A {@link android.support.v4.app.FragmentStatePagerAdapter} that returns a fragment
     * representing an object in the collection.
     */
    public static class DemoCollectionPagerAdapter extends FragmentStatePagerAdapter {

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

        @Override
        public Fragment getItem(int i) {
            Fragment fragment = new DemoObjectFragment();
            Bundle args = new Bundle();
            args.putInt(DemoObjectFragment.ARG_OBJECT, i + 1); // Our object is just an integer :-P
            fragment.setArguments(args);
            return fragment;
        }

        @Override
        public int getCount() {
            // For this contrived example, we have a 100-object collection.
            return 100;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            return "OBJECT " + (position + 1);
        }
    }

    /**
     * A dummy fragment representing a section of the app, but that simply displays dummy text.
     */

    public static class DemoObjectFragment extends Fragment {

        public static final String ARG_OBJECT = "object";

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.load_main_menu_activity, container, false);
            Bundle args = getArguments();
           //((TextView) rootView.findViewById(android.R.id.text1)).setText(
                 //   Integer.toString(args.getInt(ARG_OBJECT)));
            return rootView;
        }
    }
}
4

2 回答 2

1 
public class FirstFragment extends Fragment implements OnClickListener {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.first_fragment, container, false);
        Button nextButton = (Button) view.findViewById(R.id.button_first);
        nextButton.setOnClickListener(this);
        return view;
    }
}
于 2013-07-15T12:06:46.563 回答
1

试试这个代码。

package com.example.viewpagerexample;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.Window;
import android.view.WindowManager;

public class ViewPagerExample extends FragmentActivity {
    private MyAdapter mAdapter;
    private ViewPager mPager;
    private static Activity activity;

    /** Called when the activity is first created. */

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
        WindowManager.LayoutParams.FLAG_FULLSCREEN);
            setContentView(R.layout.activity_main);
            mAdapter = new MyAdapter(getSupportFragmentManager());
            activity = this;
            mPager = (ViewPager) findViewById(R.id.pager);
            mPager.setAdapter(mAdapter);
    }

    public static class MyAdapter extends FragmentPagerAdapter {
        public MyAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public int getCount() {
            return 3;
        }

        @Override
        public Fragment getItem(int position) {
            switch (position) {
            case 0:
                return new Fragment1();
            case 1:
                return new Fragment2();
            case 2:
                return new Fragment3();
            default:
                return new Fragment1();
            }
        }
    }
}
于 2013-07-15T11:48:07.293 回答