Question

我正在开发一个Android语言词典应用程序。我正在考虑一个分为两个阶段的收藏夹按钮：

点击一下即可将当前查看的单词添加到“收藏夹”列表中;
并且长按将允许用户查看收藏夹列表（添加的单词）。

我想知道这是否可行，如果可以，请解释一下如何做到这一点？

注意：到目前为止，我只是成功地将“收藏夹”图片按钮添加到了应用程序中，当点击它时，它会显示：“选择添加到收藏夹中的单词”。

非常感谢你。

Answer 1

假设，public class FavViewActivity extends ListActivity，您只需添加OnLongClickListener，就像添加OnClickListener一样：

btnAddFavourite = (ImageButton) findViewById(R.id.btnAddFavourite);

btnAddFavourite.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // Add code here to save the favourite, e.g. in the db.
        }
    });

btnAddFavourite.setOnLongClickListener(new View.OnLongClickListener() {

        @Override
        public boolean onLongClick(View v) {

            // Open the favourite Activity, which in turn will fetch the saved favourites, to show them.
            Intent intent = new Intent(getApplicationContext(), FavViewActivity.class);
            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            getApplicationContext().startActivity(intent);

            return false;
        }
    });

在您的数据库中，保留一个收藏表，列出标记为收藏夹的单词的id :.

为了创建一个新的活动，比如FavViewActivity，有很多指南。

Here就是其中之一。
Here是StackOverflow上的一个。
Here是文档。

如需更多帮助，请详细说明内容，并添加到目前为止您尝试过的内容。 ^ _ ^

Answer 2

使用会议室数据库可以使用此方法，可以在RecyclerView中使用“添加到收藏夹”和“显示收藏夹”。可以将保存在会议室数据库中的数据添加到收藏夹中，并在Recyclerview中检索数据。

 viewHolder.fav_btn.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
           FavoriteList favoriteList=new FavoriteList();

           int id=productList.getId();
           String image=productList.getImage();
           String name=productList.getMame();

           favoriteList.setId(id);
           favoriteList.setImage(image);
           favoriteList.setName(name);

           if (MainActivity.favoriteDatabase.favoriteDao().isFavorite(id)!=1){
viewHolder.fav_btn.setImageResource(R.drawable.ic_favorite);
               MainActivity.favoriteDatabase.favoriteDao().addData(favoriteList);

           }else {
              viewHolder.fav_btn.setImageResource(R.drawable.ic_favorite_border_black_24dp);
               MainActivity.favoriteDatabase.favoriteDao().delete(favoriteList);

           }

    }
});

房间数据库和所有代码，单击 here

Answer 3

[更新] @JOG：非常感谢。我已设法使ViewHistory工作，但仍然没有想出如何查看收藏夹列表。更具体地说，请查看我的ContentView文件：

package viettien.kadict;

import java.util.ArrayList;
import java.util.Arrays;

import viettien.kadict.R;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.graphics.Color;
import android.net.Uri;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.Window;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ImageButton;
import android.widget.Toast;

public class ContentView extends Activity {

static final private String CONTENT_TAG = "[Kadict - Content]";

static final private int SHOW_HISTORY_CODE = 0;
static final private int SHOW_FAVOURITE_CODE = 1;

static final private int MENU_BACK = Menu.FIRST;
static final private int MENU_FOWARD = Menu.FIRST+1;
static final private int MENU_LIST = Menu.FIRST+2;
static final private int MENU_HISTORY = Menu.FIRST+3;

private static final String MIMETYPE = "text/html";
private static final String ENCODING = "UTF-8";

private WebView wvContent = null;
private ImageButton btnGoBack = null;
private ImageButton btnGoForward = null;
private ImageButton btnShowHistory = null;
private ImageButton btnAddFavourite = null;

private String mCurrentWord;
private String mSelectedDB;
//private String mSelectedDBName;
private String mContentStyle;
private int mCurrentWordId;
private int mCurrentHistoryIndex = -1;

Menu menu = null;

private ArrayList<String> mWordHistory = null;

private SharedPreferences prefs;

private ProgressDialog pd = null;

// create Menu for Program
@Override
public boolean onCreateOptionsMenu(Menu menu) {
  super.onCreateOptionsMenu(menu);

  Log.i(CONTENT_TAG, "menu drawed!!");
  // Group ID
  int groupId = 0;

  // The order position of the item
  int menuItemOrder = Menu.NONE;
  this.menu=menu;
  // Added extra items to make sure there's more than six to 
  // force the extended menu to appear.
  menu.add(groupId, MENU_BACK, menuItemOrder, R.string.menuGoBack);
  menu.add(groupId, MENU_FOWARD, menuItemOrder, R.string.menuGoForward);
  menu.add(groupId, MENU_LIST, menuItemOrder, R.string.menuList);
  menu.add(groupId, MENU_HISTORY, menuItemOrder, R.string.menuHistory);

  return true;
}

// process event select Menu
public boolean onOptionsItemSelected(MenuItem item) {
    super.onOptionsItemSelected(item);

    // Find which menu item has been selected
    switch (item.getItemId()) {
        case (MENU_BACK): 
        {    
            goBack();
            break;
        }
        case (MENU_FOWARD): 
        {
            goForward();
            break;
        }
        case (MENU_LIST): 
        {
            //menuDictionaryManager();
            menuList();
            break;
        }
        case (MENU_HISTORY):
        {
            break;              
        }
    }
    return true;
}

public void menuList()
{
    /*
     * TODO
     * - save history list
     */
    Intent i = new Intent();
    i.putExtra("word", mCurrentWord);
    setResult(RESULT_OK,i);
    finish();
}

public void goBack()
{
    Log.i(CONTENT_TAG,"go back");
    String content = getHistoryContent("back");
    showContent(content);
}

public void goForward()
{
    Log.i(CONTENT_TAG,"go foward");
    String content = getHistoryContent("back");
    showContent(content);
}

@Override
public void onPause()
{
    super.onPause();
    saveHistoryToPreferences();
}

public void saveHistoryToPreferences()
{
    if (prefs.getBoolean("saveHistory", true) && mWordHistory != null && mWordHistory.size() >= 1)
    {
        StringBuilder sbHistory = new StringBuilder();
        for (String item : mWordHistory)
        {
            sbHistory.append(item);
            sbHistory.append(",");
        }

        String strHistory = sbHistory.substring(0, sbHistory.length()-1);
        SharedPreferences.Editor editor = prefs.edit();
        editor.putString("history", strHistory);
        editor.commit();
        //Log.i(CONTENT_TAG,"history = " + strHistory);
        Log.i(CONTENT_TAG,"History saved!");
    }
}

public void loadHistoryFromPreferences()
{
    if (prefs.getBoolean("saveHistory", true))
    {
        String strHistory = prefs.getString("history", "");
        Log.i(CONTENT_TAG, "History loaded");
        if (strHistory != null && !strHistory.equals(""))
        {
            mWordHistory = new ArrayList<String>(Arrays.asList(strHistory.split(",")));
        }
        else
        {
            if (mWordHistory == null)
            {
                mWordHistory = new ArrayList<String>();
            }
            else
            {
                mWordHistory.clear();
            }
        }
    }
    else
    {
        if (mWordHistory == null)
        {
            mWordHistory = new ArrayList<String>();
        }
        else
        {
            mWordHistory.clear();
        }
    }
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE); 

    setContentView(R.layout.content);
    //Log.i(CONTENT_TAG,".................onCreate.................");
    Intent i = this.getIntent();

    int wordId = i.getIntExtra("id", -1);
    mCurrentWord = i.getStringExtra("word");
    mSelectedDB = i.getStringExtra("db");
    mContentStyle = i.getStringExtra("style");
    //Log.i(CONTENT_TAG,"Style from intent = " + mContentStyle);
    //Log.d(CONTENT_TAG,"current word = " + mCurrentWord);
    prefs = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());

    loadHistoryFromPreferences();

    wvContent = (WebView) findViewById(R.id.wvContent);
    initWebview();
    String content = getContentById(wordId);
    showContent(content);

    btnShowHistory = (ImageButton) findViewById(R.id.btnShowHistory);
    btnShowHistory.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            Log.i(CONTENT_TAG, "Start showing history..");
/*              Intent i = new Intent(v.getContext(), HistoryView.class);
            HistoryList hl = new HistoryList(mWordHistory);
            i.putExtra("history", hl);*/
            startActivityForResult(new Intent(v.getContext(),HistoryView.class), SHOW_HISTORY_CODE);
            //showHistory();
        }
    });

    btnGoBack = (ImageButton) findViewById(R.id.btnGoBack);
    btnGoBack.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            Log.d(CONTENT_TAG, "Start going back");
            {
                String content = getHistoryContent("back");
                if (content == null) // end Activity now
                {
                    menuList();
                }
                else // go back to previous word
                {
                    showContent(content);
                }
                menuList();
            }

    }});

    btnGoForward = (ImageButton) findViewById(R.id.btnGoForward);
    btnGoForward.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            Log.d(CONTENT_TAG, "Start going forward");
            goForward();
        }
    });

    btnAddFavourite = (ImageButton) findViewById(R.id.btnAddFavourite);

    btnAddFavourite.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Toast toast = Toast.makeText(ContentView.this, R.string.messageWordAddedToFarvourite, Toast.LENGTH_SHORT);
                toast.show();
            }
        });

    btnAddFavourite.setOnLongClickListener(new View.OnLongClickListener() {

            @Override
            public boolean onLongClick(View v) {

                Intent intent = new Intent(getApplicationContext(), SearchActivity.class);
                intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                getApplicationContext().startActivity(intent);

                return false;
            }
        });
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) 
{
    super.onActivityResult(requestCode, resultCode, data);
    switch (requestCode)
    {
        case SHOW_HISTORY_CODE:
            Log.i(CONTENT_TAG,"resultCode = " + resultCode);
            if (resultCode == RESULT_OK) // cleared
            {
                if (data == null)
                {
                    //loadHistoryFromPreferences();
                    mWordHistory.clear();
                    Log.i(CONTENT_TAG,"History cleared");
                }
                else
                {
                    int id = data.getIntExtra("wordId", 0);
                    String dict = data.getStringExtra("dict");
                    Log.i(CONTENT_TAG,"id = " + id + " | dict = " + dict);
                    if (id > 0 && dict != null)
                    {
                        mSelectedDB = dict;
                        String content = getContentById(id);
                        //initWebview();
                        showContent(content);
                    }
                }
            }
            break;
        case SHOW_FAVOURITE_CODE:
            break;
    }
}

/*    @Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    //super.onKeyDown(keyCode, event);
    if (keyCode == KeyEvent.KEYCODE_BACK) {
        // When the user center presses, let them pick a contact.
        Log.d(CONTENT_TAG,"Backkey pressed !!!");
        if (mWordHistory != null && mWordHistory.size() > 1 && mCurrentHistoryIndex != 0)
        {
            String content = getHistoryContent("back");
            if (content == null) // end Activity now
            {
                menuList();
            }
            else // go back to previous word
            {
                showContent(content);
            }
        }
        else
        {
            menuList();
        }
        return true;
    }
    return false;
}*/


public void initWebview()
{
    setContentView(R.layout.content);
    wvContent = (WebView) findViewById(R.id.wvContent);
    wvContent.setBackgroundColor(Color.argb(250, 250, 250, 250));

    wvContent.setWebViewClient(new WebViewClient() 
    {
        public void onPageFinished(WebView view, String url)
        {
            if (pd != null)
            {
                pd.dismiss();
                pd = null;
            }
        }

        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url)
        {
            Log.i(CONTENT_TAG,"WebView link clicked; url = " + url);
            try
            {
                String arrUrlPart[] = url.split("://");

                if (arrUrlPart[0].equals("entry"))
                {
                    String content = getContentByWord(arrUrlPart[1]);
                    showContent(content);
                }
                else if (arrUrlPart[0].equals("http"))
                {
                     try {
                         /*Intent i = new Intent();

                         ComponentName comp = new ComponentName(
                                          "com.google.android.browser",
                                                 "com.google.android.browser.BrowserActivity");
                         i.setComponent(comp);
                         i.setAction("android.intent.action.VIEW");
                         i.addCategory("android.intent.category.BROWSABLE");
                         ContentURI uri = new ContentURI(url);
                         i.setData(uri);
                         startSubActivity(i, 2);*/
                         startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(url)));                              
                     } catch (Exception ex) {
                         // TODO Auto-generated catch block
                         ex.printStackTrace();
                     }                      
                }
            }
            catch (Exception ex)
            {
                ex.printStackTrace();
            }
            return true;
        }
    });
}

public String getHistoryContent(String type)
{
    String currentTerm = mSelectedDB + ":" + mCurrentWordId + ":" + mCurrentWord;

    Log.i(CONTENT_TAG,"currentTerm = " +currentTerm);
    if (mWordHistory == null || mWordHistory.isEmpty())
    {
        return null;
    }
    int pos = mWordHistory.indexOf(currentTerm);
    Log.i(CONTENT_TAG,"pos = " + pos);
    if (pos <= 0)
    {
        pos = mWordHistory.size();
    }
    String item = null;
    String searchTerm;

    if (type.equals("back"))
    {
        try
        {
            for (int i = pos-1; i >= 0 ; i--)
            {
                searchTerm = mWordHistory.get(i);
                searchTerm = searchTerm.substring(0,searchTerm.indexOf("::"));
                Log.i(CONTENT_TAG,"item = " + mWordHistory.get(i) + " - searchTerm = " + searchTerm);
                if (searchTerm.equals(mSelectedDB))
                {
                    item = mWordHistory.get(i);  
                    mCurrentHistoryIndex = i;
                    break;
                }
            }
        }
        catch (Exception ex)
        {
            Log.i(CONTENT_TAG,"Error in finding history entry");
        }

    }
    else
    {
        try
        {
            for (int i = pos; i < mWordHistory.size() ; i++)
            {
                searchTerm = mWordHistory.get(i);
                searchTerm = searchTerm.substring(0,searchTerm.indexOf("::"));
                Log.i(CONTENT_TAG,"item = " + mWordHistory.get(i) + " - searchTerm = " + searchTerm);
                if (searchTerm.equals(mSelectedDB))
                {
                    item = mWordHistory.get(i);  
                    mCurrentHistoryIndex = i;
                    break;
                }
            }
        }
        catch (Exception ex)
        {
            Log.i(CONTENT_TAG,"Error in finding history entry");
        }
    }
    if (item != null) // found previous item
    {
        Log.i(CONTENT_TAG,"item index = " + mCurrentHistoryIndex);
        String arrPart[] = item.split(":");

        Uri uri = Uri.parse("content://viettien.kadict.KadictProvider/dict/" + arrPart[0] + "/contentId/" + arrPart[1]);

        Log.i(CONTENT_TAG,"History uri = " + uri.toString());
        Cursor result = managedQuery(uri,null,null,null,null);

        String content;
        if (result != null)
        {
            result.moveToFirst();
            content = Utility.decodeContent(result.getString(result.getColumnIndex("content")));

            content = formatContent(content);

            mSelectedDB = arrPart[0];
            mCurrentWordId = Integer.parseInt(arrPart[1]);
            mCurrentWord = arrPart[2];
            return content;
        }
        else
        {
            return null;
        }
    }
    else
    {
        return null;
    }
}

public String getContentById(int id)
{
    Uri uri = Uri.parse("content://viettien.kadict.KadictProvider/dict/" + mSelectedDB + "/contentId/" + id);

    Cursor result = managedQuery(uri,null,null,null,null);

    String content;
    if (result != null)
    {
        result.moveToFirst();
        content = Utility.decodeContent(result.getString(result.getColumnIndex("content")));
        mCurrentWordId = result.getInt(result.getColumnIndex("id"));
        mCurrentWord = result.getString(result.getColumnIndex("word"));
    }
    else // Word not found
    {
        content = getString(R.string.errorWordNotFound);
        mCurrentWordId = -1;
        mCurrentWord = "";
    }
    content = formatContent(content);

    return content;
}

public String getContentByWord(String word)
{
    Uri uri = Uri.parse("content://viettien.kadict.KadictProvider/dict/" + mSelectedDB + "/contentWord/" + word);

    Log.i(CONTENT_TAG,"uri = " + uri.toString());
    Cursor result = managedQuery(uri,null,null,null,null);

    String content;
    if (result != null && result.getCount() > 0)
    {
        result.moveToFirst();
        content = Utility.decodeContent(result.getString(result.getColumnIndex("content")));
        mCurrentWordId = result.getInt(result.getColumnIndex("id"));
        mCurrentWord = result.getString(result.getColumnIndex("word"));
    }
    else
    {
        content = getString(R.string.errorWordNotFound) + word;
        mCurrentWordId = -1;
        mCurrentWord = "";
    }
    content = formatContent(content);

    return content;
}

public void saveHistory()
{
    String item = mSelectedDB + "::" + mCurrentWordId + "::" + mCurrentWord;
    if (mWordHistory.indexOf(item) == -1 && mCurrentWordId != -1) // new item
    {
        mWordHistory.add(item);
        mCurrentHistoryIndex = mWordHistory.size();

        if (menu != null)
        {
            menu.findItem(MENU_FOWARD).setEnabled(false);
            if (mWordHistory.size() == 1)
            {
                menu.findItem(MENU_BACK).setEnabled(false);
            }
        }
        //Log.i(CONTENT_TAG,"new item added " + item);
    }
}

public String formatContent(String content)
{
    StringBuilder htmlData = new StringBuilder();
    htmlData.append("<html><meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\"/>\n");
    if (mContentStyle != null && !mContentStyle.equals(""))
    {
        htmlData.append("<head><style type=\"text/css\">"+mContentStyle+"</style></head>\n");
    }
    htmlData.append("<body><font face=\"Arial\">");

    htmlData.append(content);

    htmlData.append("</font></body></html>");

    return htmlData.toString();
}

public void showContent(String content)
{
    if (content != null)
    {
        pd = ProgressDialog.show(this, "Working...", "Loading content", true,false);            
        saveHistory();
        wvContent.loadDataWithBaseURL (null, content, MIMETYPE, ENCODING,"about:blank");
    }
}


}

如何：添加到收藏夹并查看收藏夹列表

3 个答案: