问题描述
我尝试在 http://developer.android.com/training/animation 中实现一个 android 项目/screen-slide.html 我在一类中有错误
I tried to implement an android project in http://developer.android.com/training/animation/screen-slide.html and I have an error in one class
import android.os.Bundle; import android.annotation.SuppressLint; import android.app.Activity; import android.app.Fragment; import android.app.FragmentManager; import android.content.Intent; import android.support.v4.app.FragmentActivity; import android.support.v4.app.FragmentStatePagerAdapter; import android.support.v4.app.NavUtils; import android.support.v4.view.PagerAdapter; import android.support.v4.view.ViewPager; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.widget.Button; public class MainActivity extends FragmentActivity { private static final int NUM_PAGES = 5; private ViewPager mPager; private PagerAdapter mPagerAdapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mPager = (ViewPager) findViewById(R.id.pager); mPagerAdapter = new ScreenSlidePagerAdapter(getFragmentManager()); mPager.setAdapter(mPagerAdapter); mPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() { @Override public void onPageSelected(int position) { // When changing pages, reset the action bar actions since they are dependent // on which page is currently active. An alternative approach is to have each // fragment expose actions itself (rather than the activity exposing actions), // but for simplicity, the activity provides the actions in this sample. invalidateOptionsMenu(); } }); } @SuppressLint("NewApi") @Override public boolean onCreateOptionsMenu(Menu menu) { super.onCreateOptionsMenu(menu); getMenuInflater().inflate(R.menu.activity_main, menu); menu.findItem(R.id.action_previous).setEnabled(mPager.getCurrentItem() > 0); // Add either a "next" or "finish" button to the action bar, depending on which page // is currently selected. MenuItem item = menu.add(Menu.NONE, R.id.action_next, Menu.NONE, (mPager.getCurrentItem() == mPagerAdapter.getCount() - 1) ? R.string.action_finish : R.string.action_next); item.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM | MenuItem.SHOW_AS_ACTION_WITH_TEXT); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case android.R.id.home: // Navigate "up" the demo structure to the launchpad activity. // See http://developer.android.com/design/patterns/navigation.html for more. NavUtils.navigateUpTo(this, new Intent(this, MainActivity.class)); return true; case R.id.action_previous: // Go to the previous step in the wizard. If there is no previous step, // setCurrentItem will do nothing. mPager.setCurrentItem(mPager.getCurrentItem() - 1); return true; case R.id.action_next: // Advance to the next step in the wizard. If there is no next step, setCurrentItem // will do nothing. mPager.setCurrentItem(mPager.getCurrentItem() + 1); return true; } return super.onOptionsItemSelected(item); } private class ScreenSlidePagerAdapter extends FragmentStatePagerAdapter { public ScreenSlidePagerAdapter(FragmentManager fm) { super(fm); } public Fragment getItem(int position) { return ScreenSlidePageFragment.create(position); } public int getCount() { return NUM_PAGES; } } }
我正在 android 4.2 中构建项目.
I am building the project in android 4.2.
我已将代码更改为
private class ScreenSlidePagerAdapter extends FragmentStatePagerAdapter { public ScreenSlidePagerAdapter(android.support.v4.app.FragmentManager fm) { super(fm); }
和
@Override public android.support.v4.app.Fragment getItem(int position) { return Firstframe.create(position); }
然后发生错误
mPagerAdapter = new ScreenSlidePagerAdapter(getFragmentManager());
错误:构造函数 MainActivity.ScreenSlidePagerAdapter(FragmentManager) 未定义
推荐答案
改为:
mPagerAdapter = new ScreenSlidePagerAdapter(getFragmentManager());
这样做:
mPagerAdapter = new ScreenSlidePagerAdapter(getSupportFragmentManager());
因为
getFragmentManager() 配合 import android.app.FragmentManager
和
getSupportFragmentManager() 与 android.support.v4.app.FragmentManager