PreferredActivitiesDemoActivity.java

/***
  Copyright (c) 2012 CommonsWare, LLC
  Licensed under the Apache License, Version 2.0 (the "License"); you may not
  use this file except in compliance with the License. You may obtain a copy
  of the License at http://www.apache.org/licenses/LICENSE-2.0. Unless required
  by applicable law or agreed to in writing, software distributed under the
  License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
  OF ANY KIND, either express or implied. See the License for the specific
  language governing permissions and limitations under the License.
  
  Covered in detail in the book _The Busy Coder's Guide to Android Development_
    https://commonsware.com/Android
 */

package com.commonsware.android.prefact;

import android.app.ListActivity;
import android.content.ComponentName;
import android.content.IntentFilter;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.Iterator;

public class PreferredActivitiesDemoActivity extends ListActivity {
  ArrayList<IntentFilter> filters=new ArrayList<IntentFilter>();
  ArrayList<ComponentName> names=new ArrayList<ComponentName>();

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

    PackageManager mgr=getPackageManager();

    mgr.getPreferredActivities(filters, names, null);
    setListAdapter(new IntentFilterAdapter());
  }

  // from http://stackoverflow.com/a/8555153/115145

  public static <T> Iterable<T> in(final Iterator<T> iterator) {
    class SingleUseIterable implements Iterable<T> {
      private boolean used=false;

      @Override
      public Iterator<T> iterator() {
        if (used) {
          throw new IllegalStateException("Already invoked");
        }
        used=true;
        return iterator;
      }
    }
    return new SingleUseIterable();
  }

  class IntentFilterAdapter extends ArrayAdapter<IntentFilter> {
    IntentFilterAdapter() {
      super(PreferredActivitiesDemoActivity.this,
            android.R.layout.simple_list_item_2, android.R.id.text1,
            filters);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
      View row=super.getView(position, convertView, parent);
      TextView filter=(TextView)row.findViewById(android.R.id.text1);
      TextView name=(TextView)row.findViewById(android.R.id.text2);

      filter.setText(buildTitle(getItem(position)));
      name.setText(names.get(position).getClassName());

      return(row);
    }

    String buildTitle(IntentFilter filter) {
      StringBuilder buf=new StringBuilder();
      boolean first=true;

      if (filter.countActions() > 0) {
        for (String action : in(filter.actionsIterator())) {
          if (first) {
            first=false;
          }
          else {
            buf.append('/');
          }

          buf.append(action.replaceAll("android.intent.action.", ""));
        }
      }

      if (filter.countDataTypes() > 0) {
        first=true;

        for (String type : in(filter.typesIterator())) {
          if (first) {
            buf.append(" : ");
            first=false;
          }
          else {
            buf.append('|');
          }

          buf.append(type);
        }
      }

      if (filter.countDataSchemes() > 0) {
        buf.append(" : ");
        buf.append(filter.getDataScheme(0));

        if (filter.countDataSchemes() > 1) {
          buf.append(" (other schemes)");
        }
      }

      if (filter.countDataPaths() > 0) {
        buf.append(" : ");
        buf.append(filter.getDataPath(0));

        if (filter.countDataPaths() > 1) {
          buf.append(" (other paths)");
        }
      }

      return(buf.toString());
    }
  }
}