BackgroundAsyncTask.java

package fi.iki.murgo.irssinotifier;

import android.app.Activity;
import android.app.ProgressDialog;
import android.os.AsyncTask;

public abstract class BackgroundAsyncTask<A, B, C> extends AsyncTask<A, B, C> {

    private ProgressDialog dialog;
    protected final Activity activity;
    private final String titleText;
    private final String text;
    private Callback<C> callback;
    private final boolean showDialog;

    /**
     * This constructor doesn't show dialog
     */
    public BackgroundAsyncTask(Activity activity) {
        this.activity = activity;
        titleText = null;
        text = null;
        showDialog = false;
    }

    /**
     * Shows dialog with indeterminate progress bar
     */
    public BackgroundAsyncTask(Activity activity, String titleText, String text) {
        this.activity = activity;
        this.titleText = titleText;
        this.text = text;
        this.showDialog = true;
    }

    @Override
    protected void onPreExecute() {
        if (showDialog && dialog == null)
            setDialog(ProgressDialog.show(activity, titleText, text, true));
    }

    @Override
    protected void onPostExecute(C result) {
        try {
            if (dialog != null)
                dialog.dismiss();
        } catch (Exception e) {
            // nothing
        }

        if (callback != null) {
            callback.doStuff(result);
        }
    }

    public Callback<C> getCallback() {
        return callback;
    }

    public void setCallback(Callback<C> callback) {
        this.callback = callback;
    }

    public ProgressDialog getDialog() {
        return dialog;
    }

    public void setDialog(ProgressDialog dialog) {
        this.dialog = dialog;
    }
}