对话框不会出现

Question

我有一个字典应用程序的代码。如果用户在搜索框中单击列表项，我想显示带有两个按钮的对话框..但我在模拟器中测试它不会出现。我使用以下代码创建字典应用程序。这只是MainActivity calss。

mycode的：

public class Shower extends Activity {
     private TextView mTextView;
        private ListView mListView;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_shower);

        mTextView = (TextView) findViewById(R.id.text);
        mListView = (ListView) findViewById(R.id.list);

        handleIntent(getIntent());
    }


    @Override
    protected void onNewIntent(Intent intent) {
        // Because this activity has set launchMode="singleTop", the system calls this method
        // to deliver the intent if this actvity is currently the foreground activity when
        // invoked again (when the user executes a search from this activity, we don't create
        // a new instance of this activity, so the system delivers the search intent here)
        handleIntent(intent);
    }

    private void handleIntent(Intent intent) {
        if (Intent.ACTION_VIEW.equals(intent.getAction())) {
            // handles a click on a search suggestion; launches activity to show word
            Intent wordIntent = new Intent(this, WordActivity.class);
            wordIntent.setData(intent.getData());
            startActivity(wordIntent);
            finish();
        } else if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
            // handles a search query
            String query = intent.getStringExtra(SearchManager.QUERY);
            showResults(query);
        }
    }

    /**
     * Searches the dictionary and displays results for the given query.
     * @param query The search query
     */
    private void showResults(String query) {

        Cursor cursor = managedQuery(DictionaryProvider.CONTENT_URI, null, null,
                                new String[] {query}, null);

        if (cursor == null) {
            // There are no results
            mTextView.setText(getString(R.string.no_results, new Object[] {query}));
        } else {
            // Display the number of results
            int count = cursor.getCount();
            String countString = getResources().getQuantityString(R.plurals.search_results,
                                    count, new Object[] {count, query});
            mTextView.setText(countString);

            // Specify the columns we want to display in the result
            String[] from = new String[] { DictionaryDatabase.KEY_WORD,
                                           DictionaryDatabase.KEY_DEFINITION };

            // Specify the corresponding layout elements where we want the columns to go
            int[] to = new int[] { R.id.word,
                                   R.id.definition };

            // Create a simple cursor adapter for the definitions and apply them to the ListView
            SimpleCursorAdapter words = new SimpleCursorAdapter(this,
                                          R.layout.result, cursor, from, to);
            mListView.setAdapter(words);

            // Define the on-click listener for the list items
            mListView.setOnItemClickListener(new OnItemClickListener() {
                public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                    // Build the Intent used to open WordActivity with a specific word Uri
                   // Intent wordIntent = new Intent(getApplicationContext(), WordActivity.class);
                    //Uri data = Uri.withAppendedPath(DictionaryProvider.CONTENT_URI,
                                                   // String.valueOf(id));
                   // wordIntent.setData(data);
                    //startActivity(wordIntent);



            String title="Dictionary";
            String message="definition";
            AlertDialog.Builder dialog = new AlertDialog.Builder(Shower.this);
               dialog.setTitle(title);
               dialog.setMessage(message);             


                 dialog.setCancelable(false);
                 dialog.setPositiveButton("Dictionary",
                  new DialogInterface.OnClickListener() {
                     public void onClick(DialogInterface dialog, int id) {


                         Intent wordIntent = new Intent(getApplicationContext(), WordActivity.class);
                         Uri data = Uri.withAppendedPath(DictionaryProvider.CONTENT_URI,
                                                         String.valueOf(id));
                         wordIntent.setData(data);
                         startActivity(wordIntent);

                     }
                 }) ;

                 dialog.setNegativeButton("definition", 
                  new DialogInterface.OnClickListener() {
                     public void onClick(DialogInterface dialog, int id) {
                         dialog.dismiss();
                     }
                 });
                 dialog.show();
                }


                });
        }
        }




    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        //getMenuInflater().inflate(R.menu.activity_shower, menu);
      //  return true;

        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.activity_shower, menu);

        SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
        SearchView searchView = (SearchView) menu.findItem(R.id.search).getActionView();
        searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
        searchView.setIconifiedByDefault(false);

        return true;

    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.search:
                onSearchRequested();
                return true;
            default:
                return false;
        }
    }
}

Answer 1

您必须使用alertdialog构建器创建alertdialog ..

AlertDialog alert=dialog.create();

alert.show();

你的代码中的

。请参阅此link

Answer 2

试试这个：

         AlertDialog dialog = new AlertDialog.Builder(YourClassName.context).create();
    dialog.setTitle("");
    dialog.setMessage("");

   dialog.setIcon("");
  dialog.setButton(DialogInterface.BUTTON_POSITIVE,"Open whatever", new DialogInterface.OnClickListener() {
 public void onClick(DialogInterface dialog, int which) {
                                // TODO Auto-generated method stub 
Intent intent = new Intent(YourClassName.context, OtherClassName.class);
        //your code ....
                }   
                });

           dialog.show();


     return true;

      }

Answer 3

AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Are you sure you want to exit?")
       .setCancelable(false)
       .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
           public void onClick(DialogInterface dialog, int id) {
                MyActivity.this.finish();
           }
       })
       .setNegativeButton("No", new DialogInterface.OnClickListener() {
           public void onClick(DialogInterface dialog, int id) {
                dialog.cancel();
           }
       });
AlertDialog alert = builder.create();
alert.show();