I'm following this tutorial: http://huuah.com/android-progress-bar-and-thread-updating/
to learn how to make progress bars. I'm trying to show the progress bar on top of my activity and have it update the activity's table view in the background.
So I created an async task for the dialog that takes a callback:
package com.lib.bookworm;
import android.app.ProgressDialog;
import android.content.Context;
import android.os.AsyncTask;
public class UIThreadProgress extends AsyncTask<Void, Void, Void> {
private UIThreadCallback callback = null;
private ProgressDialog dialog = null;
private int maxValue = 100, incAmount = 1;
private Context context = null;
public UIThreadProgress(Context context, UIThreadCallback callback) {
this.context = context;
this.callback = callback;
}
@Override
protected Void doInBackground(Void... args) {
while(this.callback.condition()) {
this.callback.run();
this.publishProgress();
}
return null;
}
@Override protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
dialog.incrementProgressBy(incAmount);
};
@Override
protected void onPreExecute() {
super.onPreExecute();
dialog = new ProgressDialog(context);
dialog.setCancelable(true);
dialog.setMessage("Loading...");
dialog.setProgress(0);
dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
dialog.setMax(maxValue);
dialog.show();
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
if (this.dialog.isShowing()) {
this.dialog.dismiss();
}
this.callback.onThreadFinish();
}
}
And in my activity, I do:
final String page = htmlPage.substring(start, end).trim();
//Create new instance of the AsyncTask..
new UIThreadProgress(this, new UIThreadCallback() {
@Override
public void run() {
row_id = makeTableRow(row_id, layout, params, matcher); //ADD a row to the table layout.
}
@Override
public void onThreadFinish() {
System.out.println("FINISHED!!");
}
@Override
public boolean condition() {
return matcher.find();
}
}).execute();
So the above creates an async task to run to update a table layout activity while showing the progress bar that displays how much work has been done..
However, I get an error saying that only the thread that started the activity can update its views. I tried doing:
MainActivity.this.runOnUiThread(new Runnable() {
@Override public void run() {
row_id = makeTableRow(row_id, layout, params, matcher); //ADD a row to the table layout.
}
}
But this gives me synchronization errors.. Any ideas how I can display progress and at the same time update my table in the background?
Currently my UI looks like:
