Android CursorAdapter首次加载时未刷新

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问题描述

编辑我没有添加XML

EDIT I didn't add my XML

我正在编写一个用于标记选择的对话框.第一个视图是应用他们在数据库中拥有的标签.下一个屏幕是一个对话框，用于将新标签添加到它们的数据库.我正在为他们提供建议以供其使用标签.当他们开始在标签中输入内容时，我想过滤列表.我为每个屏幕使用两个自定义CursorAdapters，但是它们共享相同的ListView.我还使用CursorLoader在后台运行我的查询，这两个查询都是从支持库扩展的.

I am writing a dialog for tagging selections. The first view is applying tags they have in their db. The next screen is a dialog for adding new tags to their db. I am supplying suggestions for them to use for their tags. I want to filter the list when they begin typing in their tag. I am using two custom CursorAdapters for each screen but they share the same ListView. I am also using a CursorLoader to run my queries in the background both are extended from the support library.

当我第一次打开新标签屏幕时，出现对话框后，列表不会在Android 4.0.3中使用过滤后的光标刷新，也不会快速滚动.如果我切换到标签视图，然后返回到新的标签对话框，它将进行过滤和滚动，如它所愿..我的查询有效，并且每次在Android 2.3.3中该代码均有效.我不知道为什么这不起作用.这是我的CursorLoader和Recommendations适配器的代码.

When I open the new tag screen the first time, after the dialog comes up, the list doesn't refresh with the filtered cursor in Android 4.0.3 nor does the quick scroll work. If I switch to the tag view and then back to the new tag dialog it filters and scrolls like it should.. My query works and the code works in Android 2.3.3 every time. I can't figure out why this is not working. Here is my code for the CursorLoader and the Suggestion adapter.

package org.lds.ldssa;

import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.res.Resources;
import android.database.Cursor;
import android.os.Bundle;
import android.support.v4.app.LoaderManager;
import android.support.v4.content.CursorLoader;
import android.support.v4.content.Loader;
import android.support.v4.widget.SimpleCursorAdapter;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.*;
import org.lds.ldssa.service.MLDatabase;
import org.lds.ldssa.service.aws.Annotation;

 public class TagDialog extends AlertDialog implements LoaderManager.LoaderCallbacks<Cursor> {

private static final String TAG = "ldssa.tagdialog";
public static final int TAGLOADERID = 0;

// View Items
private EditText mEditText;
private ListView mListView;
private TextView mEmptyView;
private ProgressBar mProgressBar;
private ImageButton mNewTagButton;
private ImageButton mSortTagButton;
private TextView mTitle;
private Button mOkButton;
private Button mCancelButton;
private String mTagTitle;
private String mNewTagTitle;

private Annotation mAnnotation;
private ContentFragment mContentFragment;

private boolean isNewTagView;
private static final String KEY_NEWTAGVIEW = "new_tag_view";
private SimpleCursorAdapter mSuggestionAdapter;
private TagListAdapter mTagAdapter;

private MLDatabase mlDatabase;

protected TagDialog(Context context) {
    super(context);
}

public void onCreate(Bundle savedInstanceState){
    Context context = getContext();
    Resources r = context.getResources();

    final LayoutInflater inflater = LayoutInflater.from(context);
    View view = inflater.inflate(R.layout.dialog_tag, null);

    // Main parts of the view
    mEditText = (EditText) view.findViewById(R.id.tag_new_tag);
    mListView = (ListView) view.findViewById(android.R.id.list);
    mProgressBar = (ProgressBar) view.findViewById(R.id.tag_spin_progress_bar);
    mEmptyView = (TextView) view.findViewById(android.R.id.empty);
    mEmptyView.setVisibility(View.INVISIBLE);

    // Titlebar
    View titleBar = inflater.inflate(R.layout.dialog_tag_title, null);
    mNewTagButton = (ImageButton) titleBar.findViewById(R.id.tag_new_icon);
    mSortTagButton = (ImageButton) titleBar.findViewById(R.id.tag_sort_icon);
    mTitle = (TextView) titleBar.findViewById(R.id.tag_title);
    mTagTitle = r.getString(R.string.tag_dialog_title);
    mNewTagTitle = r.getString(R.string.tag_new_dialog_title);
    this.setCustomTitle(titleBar);

    // Buttons
    final String OK = r.getString(R.string.ok);
    final String CANCEL = r.getString(R.string.cancel);
    this.setButton(BUTTON_POSITIVE, OK, new OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) { /*Never Used*/}});
    this.setButton(BUTTON_NEGATIVE, CANCEL, new OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) { /*Never Used*/}});

    // Setup Button Listeners
    setOnShowListener(new OnShowListener() {
        @Override
        public void onShow(DialogInterface dialog) {
            Button ok = getButton(BUTTON_POSITIVE);
            ok.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    if(isNewTagView){
                        hideIMM();
                        setupTagDialog();
                        mEditText.setText("");
                    } else {
                        dismiss();
                    }
                }
            });

            Button cancel = getButton(BUTTON_NEGATIVE);
            cancel.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    if(isNewTagView){
                        hideIMM();
                        setupTagDialog();
                        mEditText.setText("");
                    } else {
                        dismiss();
                    }
                }
            });
        }
    });

    mNewTagButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            setupNewTagDialog();
        }
    });
    mSortTagButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

        }
    });

    mEditText.addTextChangedListener(new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {}

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {}

        @Override
        public void afterTextChanged(Editable s) {
           LoaderManager lm = getLoaderManager();
            if(lm != null){
                Loader l = lm.getLoader(TAGLOADERID);
                if(l != null){
                    l.forceLoad();
                } else {
                    restartLoader();
                }
            } else {
                restartLoader();
            }
        }
    });
    String[] UIBindFrom = {MLDatabase.CL_ID};
    int[] UIBindTo = {android.R.id.text1};
    mTagAdapter = new TagListAdapter(context, null);
    mSuggestionAdapter = new SimpleCursorAdapter(context, android.R.layout.simple_list_item_1, null,
            UIBindFrom, UIBindTo, 0);

    //Handle Rotations
    if(savedInstanceState == null){
        //New
        setupTagDialog();
    } else {
        //rotated
        isNewTagView = savedInstanceState.getBoolean(KEY_NEWTAGVIEW, false);
        if(isNewTagView){
            restoreTagState(savedInstanceState);
        } else {
            restoreNewTagState(savedInstanceState);
        }
    }

    LoaderManager lm = getLoaderManager();
    if(lm != null){
        lm.initLoader(TAGLOADERID, null, this);
    }

    this.setView(view);
    super.onCreate(savedInstanceState);
}

public void onStart(){
    restartLoader();
}

@Override
public Bundle onSaveInstanceState(){
    Bundle bundle = super.onSaveInstanceState();

    bundle.putBoolean(KEY_NEWTAGVIEW, isNewTagView);

    return bundle;
}

@Override
public void onBackPressed(){
    if(isNewTagView){
        hideIMM();
        setupTagDialog();
    } else {
        this.dismiss();
    }
}

private void setupTagDialog() {
    isNewTagView = false;
    mTitle.setText(mTagTitle);
    mNewTagButton.setVisibility(View.VISIBLE);
    mSortTagButton.setVisibility(View.VISIBLE);
    mEditText.setVisibility(View.GONE);
    mListView.setVisibility(View.GONE);
    mProgressBar.setVisibility(View.VISIBLE);
    mListView.setAdapter(mTagAdapter);
    restartLoader();
}

private void setupNewTagDialog() {
    isNewTagView = true;
    mTitle.setText(mNewTagTitle);
    mNewTagButton.setVisibility(View.INVISIBLE);
    mSortTagButton.setVisibility(View.INVISIBLE);
    mEditText.setVisibility(View.VISIBLE);
    mListView.setVisibility(View.GONE);
    mProgressBar.setVisibility(View.VISIBLE);
    mListView.setAdapter(mSuggestionAdapter);
    restartLoader();
}

private void restoreTagState(Bundle bundle) {
    setupTagDialog();
}

private void restoreNewTagState(Bundle bundle) {
    setupNewTagDialog();
}

public void setAnnotation(Annotation a) {
    mAnnotation = a;
}

public void setContentViewInterface(ContentFragment contentFragment) {
    mContentFragment = contentFragment;
}

private MLDatabase getDatabase() {
    if(mlDatabase == null){
        GospelLibraryApplication app = (GospelLibraryApplication) getContext().getApplicationContext();
        mlDatabase = app.getMlDatabase();
    }
    return mlDatabase;
}

public String getFilter() {
    return mEditText.getText().toString().trim();
}

public Integer getAnnotationID(){
    if(mAnnotation != null){
        return mAnnotation.getDbKey();
    }
    return -1;
}

private LoaderManager getLoaderManager(){
    if(mContentFragment == null){
        Log.d(TAG, "ContentFragment is NULL!");
        return null;
    }
    return mContentFragment.getContentActivity().getSupportLoaderManager();
}

private void restartLoader(){
    LoaderManager lm = getLoaderManager();
    if(lm != null){
        lm.restartLoader(TAGLOADERID, null, this);
    }
}

private void hideIMM(){
    InputMethodManager imm = (InputMethodManager)getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
    imm.hideSoftInputFromWindow(mEditText.getWindowToken(), 0);
}

@Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
    TagCursorLoader loader = new TagCursorLoader(getContext(), this);
    return loader;
}

@Override
public void onLoadFinished(Loader<Cursor> cursorLoader, Cursor data) {
    if(isNewTagView) {
        mSuggestionAdapter.changeCursor(data);
    } else {
        mTagAdapter.changeCursor(data);
    }
    mListView.invalidateViews();
    mProgressBar.setVisibility(View.GONE);
    mListView.setVisibility(View.VISIBLE);
}

@Override
public void onLoaderReset(Loader<Cursor> cursorLoader) {
    if(mSuggestionAdapter != null) {
        mSuggestionAdapter.changeCursor(null);
    }
}

public static class TagCursorLoader extends CursorLoader {
    private final ForceLoadContentObserver mObserver = new ForceLoadContentObserver();

    private TagDialog dialog;
    private MLDatabase mlDatabase;
    private Cursor mCursor;
    private String mFilter;
    private Integer mAnnotationID;

    // Runs on worker thread
    @Override
    public Cursor loadInBackground(){
        Cursor cursor = null;
        if(dialog.isNewTagView){
            mFilter = dialog.getFilter();
            cursor = mlDatabase.getTagSuggestions(mFilter);
        } else {
            mAnnotationID = dialog.getAnnotationID();
        }

        if(cursor != null){
            cursor.registerContentObserver(mObserver);
        }

        return cursor;

    }

    //Runs on UI thread
    @Override
    public void deliverResult(Cursor cursor){
        //Handle if canceled in the middle.
        if(isReset()){
            if(cursor != null){
                cursor.close();
            }
            return;
        }

        Cursor oldCursor = mCursor;
        mCursor = cursor;
        if(isStarted()) {
            super.deliverResult(cursor);
        }

        if(oldCursor != null && !oldCursor.equals(cursor) && !oldCursor.isClosed()) {
            oldCursor.close();
        }
    }

    public TagCursorLoader(Context context, TagDialog dialog) {
        super(context);
        this.dialog = dialog;
        mlDatabase = dialog.getDatabase();
    }

    @Override
    public void onStartLoading(){
        if(mCursor == null) {
            forceLoad();
        } else {
            if(dialog.isNewTagView && mFilter.equals(dialog.getFilter())) {
                deliverResult(mCursor);
            } else {
                forceLoad();
            }
        }
    }

    @Override
    protected void onStopLoading() {
        // Attempt to cancel the current load task if possible.
        cancelLoad();
    }

    @Override
    public void onCanceled(Cursor cursor) {
        if (cursor != null && !cursor.isClosed()) {
            cursor.close();
        }
    }

    @Override
    protected void onReset() {
        super.onReset();

        // Ensure the loader is stopped
        onStopLoading();

        if (mCursor != null && !mCursor.isClosed()) {
            mCursor.close();
        }
        mCursor = null;
    }
  }
}

package org.lds.ldssa;

import android.R;
import android.content.Context;
import android.database.Cursor;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.support.v4.widget.CursorAdapter;
import android.widget.TextView;
import org.lds.ldssa.service.MLDatabase;


public class TagSuggestionAdapter extends CursorAdapter {

    public TagSuggestionAdapter(Context context, Cursor cursor, int flags){
        super(context, cursor, flags);
    }

    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        LayoutInflater inflater = LayoutInflater.from(context);
        View v = inflater.inflate(R.layout.simple_list_item_1, parent, false);
        bindView(v, context, cursor);
        return v;
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        TextView tv = (TextView) view.findViewById(R.id.text1);
        tv.setText(cursor.getString(cursor.getColumnIndex(MLDatabase.CL_ID)));
    }
}

在此先感谢您的帮助.

XML

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/tag_layout"
    android:orientation="vertical"
    android:layout_height="wrap_content"
    android:layout_width="@dimen/min_dialog_width"
    android:padding="5dp"
    android:animateLayoutChanges="true"
    >

<!-- Here is the view to show if the list is emtpy -->
<TextView
        android:id="@android:id/empty"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="50dp"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:layout_centerInParent="true"
        android:gravity="center"
        android:text="@string/no_items"
        android:visibility="invisible"
        />

<ListView
        android:id="@android:id/list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:visibility="invisible"
        />

<ProgressBar
        android:id="@+id/tag_spin_progress_bar"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:indeterminate="true"
        />

</RelativeLayout>

CursorAdapters

Android CursorAdapter首次加载时未刷新

问题描述

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