GetAvailableComponentsTask.java

/*
 * Copyright (C) 2015 The Android Open Source Project
 *
 * 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.
 */

package com.afwsamples.testdpc.policy;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.os.AsyncTask;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.ListView;

import com.afwsamples.testdpc.R;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public abstract class GetAvailableComponentsTask<T> extends AsyncTask<Void, Void, List<T>> {
    private final Activity mActivity;
    private final int mTitleResId;

    private View mProgressView;
    private ListView mListView;
    private AlertDialog mAlertDialog;
    private Button mPositiveButton;
    private Button mNegativeButton;
    private Button mNeutralButton;

    public GetAvailableComponentsTask(Activity activity, int titleResId) {
        mActivity = activity;
        mTitleResId = titleResId;
    }

    @Override
    protected void onPreExecute() {
        View rootView = View.inflate(mActivity, R.layout.available_components_list, null);
         mAlertDialog = new AlertDialog.Builder(mActivity)
                .setTitle(mTitleResId)
                .setView(rootView)
                .setPositiveButton(android.R.string.ok, null)
                .setNeutralButton(R.string.allow_all, null)
                .setNegativeButton(android.R.string.cancel, null)
                .show();
        mProgressView = rootView.findViewById(R.id.progress_layout);
        mListView = (ListView) rootView.findViewById(android.R.id.list);

        mPositiveButton = mAlertDialog.getButton(AlertDialog.BUTTON_POSITIVE);
        mNeutralButton = mAlertDialog.getButton(AlertDialog.BUTTON_NEUTRAL);
        mNegativeButton = mAlertDialog.getButton(AlertDialog.BUTTON_NEGATIVE);

        showProgressBar(true);
    }

    @Override
    protected void onPostExecute(List<T> availableComponentsList) {
        if (mActivity == null || mActivity.isFinishing()) {
            return;
        }
        final List<ResolveInfo> availableComponentsResolveInfoList =
                getResolveInfoListFromAvailableComponents(availableComponentsList);
        PackageManager packageManager = mActivity.getPackageManager();
        Collections.sort(availableComponentsResolveInfoList,
                new ResolveInfo.DisplayNameComparator(packageManager));
        final List<String> permittedComponentsList = getPermittedComponentsList();
        final AvailableComponentsInfoArrayAdapter availableComponentsInfoArrayAdapter
                = new AvailableComponentsInfoArrayAdapter(mActivity,
                        availableComponentsResolveInfoList, permittedComponentsList);
        mListView.setAdapter(availableComponentsInfoArrayAdapter);
        mListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int pos, long id) {
                availableComponentsInfoArrayAdapter.onItemClick(parent, view, pos, id);
            }
        });

        showProgressBar(false);
        mPositiveButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                ArrayList<String> selectedComponents =
                        availableComponentsInfoArrayAdapter.getSelectedComponents();
                if (selectedComponents != null) {
                    setPermittedComponentsList(selectedComponents);
                }
                mAlertDialog.dismiss();
            }
        });
        mNeutralButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                setPermittedComponentsList(null);
                mAlertDialog.dismiss();
            }
        });
    }

    private void showProgressBar(boolean show) {
        if (show) {
            mProgressView.setVisibility(View.VISIBLE);
            mListView.setVisibility(View.GONE);
        } else {
            mProgressView.setVisibility(View.GONE);
            mListView.setVisibility(View.VISIBLE);
        }
        mPositiveButton.setEnabled(!show);
        mNeutralButton.setEnabled(!show);
        mNegativeButton.setEnabled(!show);
    }

    protected abstract List<ResolveInfo> getResolveInfoListFromAvailableComponents(
            List<T> availableComponentsList);

    protected abstract List<String> getPermittedComponentsList();

    protected abstract void setPermittedComponentsList(List<String> permittedComponentsList);
}