com.commonsware.android.leak.configchange.AsyncDemoFragment.java Source code

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Here is the source code for com.commonsware.android.leak.configchange.AsyncDemoFragment.java

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/***
  Copyright (c) 2008-2015 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.leak.configchange;

import android.os.AsyncTask;
import android.os.Bundle;
import android.os.SystemClock;
import android.support.v4.app.ListFragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Button;
import java.util.ArrayList;

public class AsyncDemoFragment extends ListFragment implements View.OnClickListener {
    private static final String[] items = { "lorem", "ipsum", "dolor", "sit", "amet", "consectetuer", "adipiscing",
            "elit", "morbi", "vel", "ligula", "vitae", "arcu", "aliquet", "mollis", "etiam", "vel", "erat",
            "placerat", "ante", "porttitor", "sodales", "pellentesque", "augue", "purus" };
    private ArrayList<String> model = new ArrayList<String>();
    private ArrayAdapter<String> adapter = null;
    private AddStringTask task = null;
    private Button btnAgain = null;

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

        setRetainInstance(true);

        task = new AddStringTask();
        task.execute();

        adapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, model);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return (inflater.inflate(R.layout.main, container, false));
    }

    @Override
    public void onViewCreated(View v, Bundle savedInstanceState) {
        super.onViewCreated(v, savedInstanceState);

        getListView().setScrollbarFadingEnabled(false);
        setListAdapter(adapter);

        getAgain().setOnClickListener(this);

        if (task != null) {
            getAgain().setEnabled(false);
        }
    }

    @Override
    public void onDestroy() {
        if (task != null) {
            task.cancel(false);
        }

        super.onDestroy();
    }

    private Button getAgain() {
        if (btnAgain == null) {
            btnAgain = (Button) getView().findViewById(R.id.again);
        }

        return (btnAgain);
    }

    @Override
    public void onClick(View v) {
        getAgain().setEnabled(false);
        adapter.clear();
        task = new AddStringTask();
        task.execute();
    }

    class AddStringTask extends AsyncTask<Void, String, Void> {
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
        }

        @Override
        protected Void doInBackground(Void... unused) {
            for (String item : items) {
                if (isCancelled())
                    break;

                publishProgress(item);
                SystemClock.sleep(400);
            }

            return (null);
        }

        @Override
        protected void onProgressUpdate(String... item) {
            if (!isCancelled()) {
                adapter.add(item[0]);
            }
        }

        @Override
        protected void onPostExecute(Void unused) {
            task = null;
            getAgain().setEnabled(true);
        }
    }
}