Question

我遇到了Android中的cardflip动画问题。我正在关注他们的向导，并试图选择AnimationsDemo的一部分来试图理解这一点。但我已经创建了XML中的所有卡片翻转和输出，以及XML中的卡片正面和背面布局。当我尝试在onCreate中添加片段时，我不断收到错误消息。我不确定触发错误是什么，因为代码看起来像他们使用的示例代码。我已经在下面提供了错误消息和jave代码。谢谢你的时间。

public class MainActivity extends ActionBarActivity {
    /**
     * Whether or not we're showing the back of the card (otherwise showing the front).
     */
    private boolean mShowingBack = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        if (savedInstanceState == null) {
            getFragmentManager()
            .beginTransaction()
            .add(R.id.container, new CardFrontFragment())
            .commit();
        }else {
            mShowingBack = (getFragmentManager().getBackStackEntryCount() > 0);
        }

            /**
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.container, new PlaceholderFragment()).commit();
                    */
    }

    private void flipCard() {
        if (mShowingBack) {
            getFragmentManager().popBackStack();
            return;
        }

        // Flip to the back.

        mShowingBack = true;

        // Create and commit a new fragment transaction that adds the fragment for the back of
        // the card, uses custom animations, and is part of the fragment manager's back stack.

        getFragmentManager()
                .beginTransaction()

                // Replace the default fragment animations with animator resources representing
                // rotations when switching to the back of the card, as well as animator
                // resources representing rotations when flipping back to the front (e.g. when
                // the system Back button is pressed).
                .setCustomAnimations(
                        R.animator.card_flip_right_in, R.animator.card_flip_right_out,
                        R.animator.card_flip_left_in, R.animator.card_flip_left_out)

                // Replace any fragments currently in the container view with a fragment
                // representing the next page (indicated by the just-incremented currentPage
                // variable).
                .replace(R.id.container, new CardBackFragment())

                // Add this transaction to the back stack, allowing users to press Back
                // to get to the front of the card.
                .addToBackStack(null)

                // Commit the transaction.
                .commit();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @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();
        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 {

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_main, container,
                    false);
            return rootView;
        }
    }

    /**
     * A fragment representing the front of the card.
     */
    public static class CardFrontFragment extends Fragment {
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            return inflater.inflate(R.layout.card_front, container, false);
        }
    }

    /**
     * A fragment representing the back of the card.
     */
    public static class CardBackFragment extends Fragment {
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            return inflater.inflate(R.layout.card_back, container, false);
        }
    }

}

错误：

The method add(int, Fragment) in the type FragmentTransaction is not applicable for the arguments (int, MainActivity.CardFrontFragment) MainActivity.java   /Lab6b/src/you/ca/mohawk/lab6b  line 28 Java Problem

Answer 1

似乎问题应该是您的Fragment导入。

如果您正在使用片段支持库，那么

import android.support.v4.app.Fragment;

和片段管理器实例应该是

getSupportFragmentManager()

否则，如果您使用默认片段，则将导入更改为

import android.app.Fragment;

Android，cardflip动画，片段不显示

1 个答案: