Question

修改

我一直在搜索和阅读很多关于这个主题的内容，但我找不到解决问题的方法。我不知道我做错了什么或设计错误或是什么。

我的活动中有一个片段，这个片段有三种不同的布局出现或消失（这取决于用户做了什么或正在做什么）。另外一个视图组是创建动态添加新的TextViews。当屏幕方向发生变化时，我想保留片段的所有视图，留下像这样看不见的布局，保持所有TextView像它们一样，等等。

我知道当屏幕方向发生变化时，片段和活动的生命周期是如何工作的，但我不知道如何管理它。如何以及从何处恢复仍在内存中的片段，如何恢复视图，并将其返回onCreateView。我放弃了对此的迷惑。

这是xml片段

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:focusable="true"
android:focusableInTouchMode="true"
android:weightSum="1">

<RelativeLayout
        android:id="@+id/top_layout"
        android:layout_width="match_parent"
        android:layout_height="40dp"
        android:padding="8dp"
        android:animateLayoutChanges="true"
        android:weightSum="1"
        android:background="#fc033967">

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="15sp"
            android:fontFamily="sans-serif-condensed"
            android:textColor="#ffffff"
            android:text="@string/scan_new_code_location"
            android:layout_marginLeft="5dp"
            android:layout_marginRight="20dp"
            android:layout_gravity="center_vertical"
            android:id="@+id/location_textView" />

        <LinearLayout
            android:id="@+id/new_location_layout"
            android:layout_width="wrap_content"
            android:layout_gravity="center_vertical"
            android:layout_height="wrap_content"
            android:orientation="horizontal">

            <ImageButton
                    android:id="@+id/new_location_image"
                    android:layout_width="18dp"
                    android:layout_height="18dp"
                    android:background="@android:color/transparent"
                    android:layout_marginLeft="20dp"
                    android:src="@drawable/ic_action_new"
                    android:layout_gravity="center_vertical"/>

                <Button
                    android:id="@+id/boton_nuevaLoc"
                    android:text="@string/newLocation"
                    android:fontFamily="sans-serif-condensed"
                    android:textColor="#ffffff"
                    android:textSize="15sp"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_marginLeft="5dp"
                    android:layout_marginRight="20dp"
                    android:background="@android:color/transparent"
                    android:layout_gravity="center_vertical"
                    />

        </LinearLayout>

        <RelativeLayout
            android:id="@+id/cancel_ingress_layout"
            android:layout_gravity="center_vertical"
            android:layout_width="40dp"
            android:layout_height="match_parent"
            android:layout_alignParentEnd="true"
            android:layout_alignParentTop="true"
            android:layout_alignParentBottom="true">
        </RelativeLayout>

    </RelativeLayout>


<RelativeLayout
    android:id="@+id/location_container"
    android:layout_width="match_parent"
    android:layout_height="40dp"
    android:padding="8dp"
    android:layout_gravity="center"
    android:animateLayoutChanges="true"
    android:weightSum="1"
    android:background="#fc033967">


    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_vertical"
        android:orientation="horizontal">

        <ImageButton
            android:id="@+id/location_image"
            android:layout_width="18dp"
            android:layout_height="18dp"
            android:background="@android:color/transparent"
            android:layout_marginLeft="20dp"
            android:src="@android:drawable/ic_menu_mylocation"
            android:layout_gravity="center_vertical"/>

        <TextView
            android:id="@+id/added_location_textView"
            android:text="@string/newLocation"
            android:fontFamily="sans-serif-condensed"
            android:textColor="#ffffff"
            android:textSize="15sp"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="5dp"
            android:layout_marginRight="20dp"
            android:background="@android:color/transparent"
            android:layout_gravity="center_vertical"
            />

    </LinearLayout>

    <RelativeLayout
        android:id="@+id/close_location_container"
        android:layout_width="40dp"
        android:layout_height="match_parent"
        android:layout_alignParentEnd="true"
        android:layout_alignParentTop="true"
        android:layout_alignParentBottom="true">

        <ImageButton
            android:id="@+id/close_location_image"
            android:layout_width="18dp"
            android:layout_height="18dp"
            android:background="@android:color/transparent"
            android:layout_marginLeft="20dp"
            android:src="@android:drawable/ic_menu_send"
            android:layout_gravity="center_vertical"/>

    </RelativeLayout>

</RelativeLayout>

<LinearLayout android:id="@+id/container"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:background="@android:color/transparent"
        android:layout_marginTop="15dp"
        android:layout_marginRight="10dp"
        android:layout_marginLeft="10dp"
        android:animateLayoutChanges="true"
        android:visibility="invisible"/>



<EditText
        android:id="@+id/scan_reader_EditText"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="500dp"
        android:inputType="text"/>

</LinearLayout>

这是代码的一部分

public class LocationFragment extends Fragment {


    private static final String TAG = "LocationFragment";
    private static final String CSV = ".csv";
    private final int scapeChar = KeyEvent.KEYCODE_ENTER;
    private final int MODE_FIRST = 0;
    private final int SHARED_INTENT = 1;

    //Graphics elements
    @Bind(R.id.top_layout) RelativeLayout topLayout;
    @Bind(R.id.new_location_layout) LinearLayout addLocationLayout;
    @Bind(R.id.new_location_image) ImageButton newLocationImage;
    @Bind(R.id.boton_nuevaLoc) Button newLocationButton;
    @Bind(R.id.cancel_ingress_layout) RelativeLayout cancelScanLayout;
    @Bind(R.id.location_textView) TextView locationTextView;
    @Bind(R.id.scan_reader_EditText) EditText scanReaderEditText;
    @Bind(R.id.container) ViewGroup containerLayout;
    @Bind(R.id.location_container) RelativeLayout closeLayout;
    @Bind(R.id.added_location_textView) TextView addedLocation;
    @Bind(R.id.close_location_image) ImageButton closeImageButton;
    static ViewGroup panelIngresarItem;


    private boolean scanLocationMode;
    private float translation;
    private DatabaseManager dbm = DatabaseManager.getInstance();
    private String locationCode;
    private Location location;
    private List<Item> items;
    private View.OnClickListener addItemListener;
    private String folderPath;



    private OnFragmentInteractionListener mListener;

    public LocationFragment() {
        // Required empty public constructor
    }

    public static LocationFragment newInstance() {
        LocationFragment fragment = new LocationFragment();
        Bundle args = new Bundle();
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setRetainInstance(true);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View rootView = inflater.inflate(R.layout.fragment_location, container, false);
        ButterKnife.bind(this,rootView);
        return rootView;
    }

    public void onViewCreated(View view, Bundle savedInstanceState){
        locationTextView.setVisibility(View.GONE);
        translation = topLayout.getMeasuredWidth() - addLocationLayout.getMeasuredWidth() +
                newLocationButton.getMeasuredWidth();
        cancelScanLayout.setOnClickListener(new CloseButtonListener());
        cancelScanLayout.setClickable(false);

        // Add item listener, for only create one listener
        addItemListener = new AddItemListener();

        closeImageButton.setOnClickListener(new CloseLocationListener());

        panelIngresarItem = (ViewGroup) LayoutInflater.from(this.getActivity()).inflate(
                R.layout.new_item_panel,containerLayout,false);
        panelIngresarItem.setOnClickListener(addItemListener);

        scanLocationMode = true;
        closeLayout.setVisibility(View.GONE);
        super.onViewCreated(view,savedInstanceState);
    }

    @Override
    public void onResume(){
        super.onResume();
        containerLayout.removeAllViews();
        populateItemList();
    }


    public void onButtonPressed(Uri uri) {
        if (mListener != null) {
            mListener.onFragmentInteraction(uri);
        }
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
    }

    @Override
    public void onDetach() {
        super.onDetach();
        mListener = null;
    }


    private void addLocationAnimation(){
        RotateAnimation ranim = (RotateAnimation) AnimationUtils.loadAnimation(getContext(),R.anim.rotate_image);
        ranim.setDuration(400);
        ranim.setInterpolator(new DecelerateInterpolator());
        ranim.setFillAfter(true);
        ranim.setFillEnabled(true);

        translation = topLayout.getMeasuredWidth() - addLocationLayout.getMeasuredWidth() +
                newLocationButton.getMeasuredWidth();

        newLocationButton.setVisibility(View.GONE);
        TranslateAnimation anim =
                new TranslateAnimation(0,translation,0,0);
        anim.setDuration(400);
        anim.setFillAfter(true);
        anim.setFillEnabled(true);
        newLocationImage.startAnimation(ranim);
        addLocationLayout.startAnimation(anim);

        cancelScanLayout.setClickable(true);

        locationTextView.setVisibility(View.VISIBLE);

        enableScanner();

    }

    private void populateItemList(){
        if (location != null) {
            containerLayout.removeAllViews();
            containerLayout.addView(panelIngresarItem);
            items = dbm.getItemListByLocation(location);
            for (Item e : items) {
                String code = e.getInventoryCode();
                addItem(code);
            }
        }
    }

    private void callItemEditForm(String code) {
        Intent itemFormActivity = new Intent(getActivity(),ItemFormActivity.class);
        itemFormActivity.putExtra("Item", code);
        itemFormActivity.putExtra("Location",locationCode);
        startActivity(itemFormActivity);
    }

    private void scanLocation(String code){
        folderPath = Environment.getExternalStorageDirectory()+
                File.separator+getResources().getString(R.string.folder)+File.separator
                + locationCode;
        if (dbm.existLocation(code)){
            new AlertDialog.Builder(getActivity())
                    .setTitle(R.string.dialog_tittle)
                    .setMessage(R.string.dialog_message)
                    .setPositiveButton(R.string.positive_button, new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int which) {
                            removeHoleDB();
                        }
                    })
                    .setNegativeButton(R.string.negative_button, new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int which) {
                        }
                    })
                    .setIcon(android.R.drawable.ic_dialog_alert)
                    .show();
        }
        locationCode = code;
        containerLayout.setVisibility(View.VISIBLE);
        location = dbm.getLocation(locationCode);
        scanLocationMode = false;
        addedLocation.setText(locationCode);
        topLayout.setVisibility(View.GONE);
        closeLayout.setVisibility(View.VISIBLE);
        containerLayout.addView(panelIngresarItem);
        populateItemList();
    }

    private void addItem (String code) {
        ((TextView)panelIngresarItem.findViewById(R.id.new_item_textView)).setText(code);
        ((ImageView)panelIngresarItem.findViewById(R.id.new_item_image)).setVisibility(View.GONE);
        panelIngresarItem.setOnClickListener(null);
        //TODO add listener
        panelIngresarItem = (ViewGroup) LayoutInflater.from(this.getActivity()).inflate(
                R.layout.new_item_panel,containerLayout,false);
        panelIngresarItem.setOnClickListener(addItemListener);
        containerLayout.addView(panelIngresarItem,0);
    }


    @OnClick(R.id.boton_nuevaLoc) void addNewLocation(){
        addLocationAnimation();
    }

    class CloseButtonListener implements View.OnClickListener {
        @Override
        public void onClick(View v) {
            locationTextView.setVisibility(View.GONE);
            RotateAnimation ranim = (RotateAnimation) AnimationUtils.loadAnimation(getContext(),R.anim.rotate_image_back);
            ranim.setDuration(400);
            ranim.setInterpolator(new DecelerateInterpolator());
            ranim.setFillAfter(true);
            ranim.setFillEnabled(true);
            newLocationButton.setVisibility(View.VISIBLE);
            TranslateAnimation anim =
                    new TranslateAnimation(translation,0,0,0);
            anim.setDuration(400);
            anim.setFillAfter(true);
            anim.setFillEnabled(true);
            newLocationImage.startAnimation(ranim);
            addLocationLayout.startAnimation(anim);
            disableScanner();
            cancelScanLayout.setClickable(false);
        }
    }

    private class BarcodeEdittextListener implements TextView.OnEditorActionListener {
        @Override
        public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
            if ( (actionId == EditorInfo.IME_ACTION_DONE) ||
                    (event.getAction() == KeyEvent.ACTION_DOWN) && event.getKeyCode() == scapeChar ){
                String code = v.getText().toString();
                    if(!code.equals("")) {
                        if (scanLocationMode)
                            scanLocation(code);
                        else {
                            addItem(code);
                            callItemEditForm(code);
                        }
                        v.setText("");
                        return true;
                    }
                }
            return false;
        }
    }

    class AddItemListener implements View.OnClickListener{
        @Override
        public void onClick(View v) {
            callItemEditForm("N/A");
        }
    }


    class CloseLocationListener implements View.OnClickListener{
        @Override
        public void onClick(View v) {
            deleteAndSend();
            /*
            new AlertDialog.Builder(getActivity())
                    .setTitle(R.string.dialog_tittle)
                    .setMessage(R.string.dialog_message)
                    .setPositiveButton(R.string.positive_button, new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int which) {
                            deleteAndSend();
                        }
                    })
                    .setNegativeButton(R.string.negative_button, new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int which) {
                        }
                    })
                    .setIcon(android.R.drawable.ic_dialog_alert)
                    .show();
                    */
        }
    }

}

和活动代码

public class MainActivity extends AppCompatActivity {


    private FragmentManager fm;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        fm = getSupportFragmentManager();
        fm.beginTransaction()
                .replace(R.id.container_fragment, new LocationFragment())
                .commit();
        getSupportActionBar().setDisplayShowHomeEnabled(true);
        getSupportActionBar().setIcon(R.drawable.ic_launcher_other);
    }

}

*************** EDIT ********

行。由于Endzeit，我解决了这个问题。

我需要这样做：在我的片段中，我创建了一个View变量来引用片段的视图并保留实例。然后，如果有一个保存的实例，我在onCreateView中返回对我保存的视图的引用。像这样： public class LocationFragment extends Fragment {

    private static final String TAG = "LocationFragment";

    //Graphics elements
    @Bind(R.id.top_layout) RelativeLayout topLayout;
                .
                .
                .
    static ViewGroup panelIngresarItem;
    **View rootView**;


    public LocationFragment() {
        // Required empty public constructor
    }

    public static LocationFragment newInstance() {
        LocationFragment fragment = new LocationFragment();
        Bundle args = new Bundle();
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        **setRetainInstance(true)**;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        **if (savedInstanceState == null)** {
            **rootView = inflater.inflate(R.layout.fragment_location, container, false);**
            ButterKnife.bind(this, rootView);
        }

        **return rootView;**
    }

    public void onViewCreated(View view, Bundle savedInstanceState){

        if(savedInstanceState == null) {
            locationTextView.setVisibility(View.GONE);
            translation = topLayout.getMeasuredWidth() - addLocationLayout.getMeasuredWidth() +
                    newLocationButton.getMeasuredWidth();
            cancelScanLayout.setOnClickListener(new CloseButtonListener());
            cancelScanLayout.setClickable(false);

            // Add item listener, for only create one listener
            addItemListener = new AddItemListener();

            closeImageButton.setOnClickListener(new CloseLocationListener());

            panelIngresarItem = (ViewGroup) LayoutInflater.from(this.getActivity()).inflate(
                    R.layout.new_item_panel, containerLayout, false);
            panelIngresarItem.setOnClickListener(addItemListener);

            scanLocationMode = true;
            closeLayout.setVisibility(View.GONE);
            super.onViewCreated(view, savedInstanceState);
        }
    }
                .
                .
                .

}

然后在活动中将片段放入FragmentManager并在存在已保存的实例时再次将其取出

public class MainActivity extends AppCompatActivity {


    private FragmentManager fm;
    public static final String FRAG_LOCATION = "frag_loc";
    private LocationFragment fragmentLocation;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        fm = getSupportFragmentManager();
        setContentView(R.layout.activity_main);
        if (savedInstanceState == null) {
            fragmentLocation = new LocationFragment();
        } else {
            fragmentLocation = (LocationFragment) fm
                    .getFragment(savedInstanceState,FRAG_LOCATION);
        }

        fm.beginTransaction()
                .replace(R.id.container_fragment, fragmentLocation)
                .commit();

        getSupportActionBar().setDisplayShowHomeEnabled(true);
        getSupportActionBar().setIcon(R.drawable.ic_launcher_other);
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        if(fragmentLocation != null) {
            getSupportFragmentManager().putFragment(outState,FRAG_LOCATION, fragmentLocation);
        }

        super.onSaveInstanceState(outState);
    }
                            .
                            .
                            .

}

Answer 1

我想你想要在旋转时保存你的片段和活动的状态。

您必须将片段保存在您的活动onSaveInstanceState()方法上。

要实现这一点，请将代码更改为：

    public static final String TAG_FRAG_LOCATION = "key_frag_loc";  
    private LocationFragment fragmentLocation;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

    ...

    fm = getSupportFragmentManager();

    if(savedInstanceState != null) {
        fragmentLocation = (LocationFragment) fragmentManager
                .findFragmentByTag(savedInstanceState.getString(TAG_FRAG_LOCATION));
    } else {
        fragmentLocation = new LocationFragment(); 
    }

    fm.beginTransaction()
                .replace(R.id.container_fragment, fragmentLocation)
                .commit();

     ...
    }


    @Override
    public void onSaveInstanceState(Bundle outState) {
        if(fragmentLocation != null) {
            outState.putString(TAG_FRAG_EXAMS, fragmentLocation.getTag());
        }

        super.onSaveInstanceState(outState);
    }

在配置字符

1 个答案: