I am creating an Android activity and starting a service from this activity using the following code. Now I want to display text "Hello user" from this service to screen, meaning service should trigger this display. I could use Toast.maketext.show but the display will disappear after couple of seconds.
new Thread(new Runnable() {
#Override
public void run() {
startAdapterIntent.setAction("START_ADAPTER");
startService(startAdapterIntent);
System.out.println("Thread2: Adapter Service started.");
}
}).start();
How do I do that?
I tried to use this link:
Making changes to Main Activity UI from thread in Service
and its (probably) parent link
http://developer.android.com/reference/android/app/Service.html
section "Remote Messenger Service Sample"
While using this second link, the onServiceConnected part of ServiceConnection doesn't seem to be working? Please help. Thank you.
From within your service you should create a handler that can be triggered by a timer task, the handler should be the one directly responsible of doing the communication with the currently active UI thread..an example would be
long delay = 3000;
long period = 3000;
TimerTask mDoTask = new TimerTask() {
#Override
public void run() {
xHandler.sendMessage(Message.obtain(xHandler, SOME_OPERATION));
}
};
mT.scheduleAtFixedRate(mDoTask, delay, period);
Handler xHandler=new Handler(){
#Override
public void handleMessage(Message message){
switch (message.what){
case SOME_OPERATION:
YourMethod();// in this method you can display your text
break;
}
}
};
Related
I created a .razor Notification Component in Blazor, and I'm trying to autoclose the notification div after xx seconds.
So far it works with this Method
private async Task CloseToast(Guid Id, bool autoclose = false)
{
if (autoclose)
{
await Task.Delay(TimeSpan.FromSeconds(5));
}
//Code to remove the notification from list
StateHasChanged();
}
The problem is that for 5 seconds the UI data binding is stuck, any one way or two way binding update to variables (text fields etc..) is on hold until the Notification is closed and the Task resumes.
How can I launch a method or code block after xx seconds without blocking the main UI task in Blazor?
A component with a timer that counts back
<h3>#Time</h3>
#code {
[Parameter] public int Time { get; set; } = 5;
public async void StartTimerAsync()
{
while (Time > 0)
{
Time--;
StateHasChanged();
await Task.Delay(1000);
}
}
protected override void OnInitialized()
=> StartTimerAsync();
}
Usage:
<Component />
<Component Time="7"/>
Tested on client side Blazor. Should behave the same way in server-side Blazor.
Hope this helps
You can use .NET Timer from System.Timers as well and set the Delay in milisec. When it elapsed event will triggered and you can put your logic into the event handler. If you don't want to bother with all the config and Disposing of Timer you can use this Nuget package. It is a very convenient wrapper for the Timer with many extra features see docs.
<AdvancedTimer Occurring="Times.Once()" IntervalInMilisec="#_closeInMs" AutoStart="true" OnIntervalElapsed="#(e => { IsVisible = false; })" />
#code {
private int _closeInMs = 5000;
...
}
The official Blazor Server EFCore sample project includes this as an example, in TextFilter.razor. The essence of the code is:
Timer? timer;
// ... code in a function to start the timer
timer?.Dispose();
timer = new(DebounceMs);
timer.Elapsed += NotifyTimerElapsed;
timer.Enabled = true;
private async void NotifyTimerElapsed(object? sender, ElapsedEventArgs e)
{
timer?.Dispose();
timer = null;
// SomeMethodAsync will need to call StateHasChanged()
InvokeAsync(() => SomeMethodAsync());
}
and a Dispose() function for the page to dispose any timer in progress when user navigates away.
I have a main activity with 6 buttons. Every button starts a new activity.
The program worked well but after that I changed some graphical attributes and made some changes in the theme a mistake occurred . I should press back button 3 times to return from an activity or exit from the main activity. Any suggestions?
btn_weeks.setOnTouchListener(new OnTouchListener() {
#Override
public boolean onTouch(View arg0, MotionEvent arg1) {
Intent i = new Intent(MainActivity.this, Weeks.class);
startActivity(i);
return false;
}
});
Buttons should implements View.OnClickListener and not OnTouchListener.
im having a problem when the app is down. the function stop() in the file "my application" save the current Form, but when i try to make a download and i put the app in background task , when try go back to the app , the app is keeping the dialog "loading" forever... i don't know how to finish the current download in background and show the next Form when go back to the app.
the code of "myapplication" file:
private Form current;
public void start() {
if(current != null){
current.show();
return;
}
new StateMachine("/theme");
}
public void stop() {
current = Display.getInstance().getCurrent();
}
Just do something like:
if(current instanceof Dialog) {
current = null;
}
I'm making kind-of an audio player. Currently I have a MediaPlayer running in the Activity itself (which I know is bad). There is a SeekBar on the screen which gets updated as the music plays, like so:
private Runnable mUpdateTimeTask = new Runnable() {
public void run()
{
long totalDuration = mp.getDuration();
long currentDuration = mp.getCurrentPosition();
songTotalDurationLabel.setText("" + utils.millisecondsToTimer(totalDuration));
songCurrentDurationLabel.setText("" + utils.millisecondsToTimer(currentDuration));
int progress = (int)(utils.getProgressPercentage(currentDuration, totalDuration));
songProgressBar.setProgress(progress);
if(mp.isPlaying())
mHandler.postDelayed(this, 100);
else
mHandler.removeCallbacks(mUpdateTimeTask);
}
};
Once the user presses the back button or kills it from the recent apps list, the music stops.
Now I want the music to run in the background, so looking around the internet I found to run it in a Service, and calling startService() from Activity. Also I have a notification come up when music is playing and removed when it is paused.
I understand from a service I'll get the music to play even when app gets closed. But what I didn't understand is, if the user taps on the notification given the service is running, the activity restarts with the SeekBar at progress = 0.
How do I get the UI to update the SeekBar to the correct value from the Service after the activity restarts?
Figured it out!
The solution is to get the running services using the ActivityManager and find your service like this
private boolean fooRunning()
{
ActivityManager manager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
for(RunningServiceInfo service : manager.getRunningServices(Integer.MAX_VALUE))
{
if("com.name.packagename.foo".equals(service.service.getClassName()))
{
return true;
}
}
return false;
}
If this method returns true, bind to the service and get the current position from the MediaPlayer object
public void bindToService()
{
if(fooRunning())
{
bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
serviceExists = true;
}
else
serviceExists = false;
}
private ServiceConnection mConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName className, IBinder serviceBinder)
{
bar binder = (bar) serviceBinder;
mService = binder.getService();
if(serviceExists)
{
int getProgress = mService.mp.getCurrentPosition();
// mp is the MediaPlayer object in the service
seekbar.setProgress(getProgress);
}
}
#Override
public void onServiceDisconnected(ComponentName className)
{
}
};
The Service class is like this:
public class foo extends Service
{
private MediaPlayer mp = new MediaPlayer();
private final IBinder mBinder = new bar();
public class bar extends Binder
{
public foo getService()
{
return foo.this;
}
}
#Override
public IBinder onBind(Intent intent)
{
return mBinder;
}
}
Hope this helps someone!
I need to register different share charm listener for every page. I have 2 pages. I added following code in every one:
DataTransferManager.GetForCurrentView().DataRequested += App_DataRequested;
I added it in constructor of one page and in UserControl_Loaded event of another (first page just doesn't have UserControl_Loaded so why I added it directly to constructor). At the moment when second page tryting to load, I got exception:
WinRT information: An event handler has already been registered
Additional information: A method was called at an unexpected time.
Where should I place it and what is "right" time to do this??
Also it looks confusing that we have different DataTransferManager for every view, but only one is active at current time. Ever more, I noticed, if you add only one listener for first page, other pages will share this listener anyway. If I have only one shared listener for all pages, is it correct register it in app.xaml.cs?
The way I resolved this issue was to deregister the event in the onNavigatedfrom event as below:
protected override void OnNavigatedFrom(NavigationEventArgs e)
{
DataTransferManager.GetForCurrentView().DataRequested -= App_DataRequested;
base.OnNavigatedFrom(e);
}
In BasePage.cs in constructor I added
public BasePage()
{
if (!_isListenToDataRequested)
{
_isListenToDataRequested = true;
DataTransferManager manager = DataTransferManager.GetForCurrentView();
manager.DataRequested += AppDataRequested;
}
}
private async void AppDataRequested(DataTransferManager sender, DataRequestedEventArgs args)
{
IShareable shareable = Frame.Content as IShareable;
if (shareable != null)
{
DataRequestDeferral deferral = args.Request.GetDeferral();
await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => shareable.AppDataRequested(sender, args));
deferral.Complete();
}
}
And all my pages look like
public sealed partial class ContentPage : IShareable
{
public void AppDataRequested(DataTransferManager sender, DataRequestedEventArgs args)
{...}
}
Another solution was run this as below
private DataTransferManager dataTransferManager;
Put this in page loaded event
this.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, new DispatchedHandler(() =>
{
this.dataTransferManager = DataTransferManager.GetForCurrentView();
this.dataTransferManager.DataRequested += new TypedEventHandler<DataTransferManager, DataRequestedEventArgs>(this.OnDataRequested);
}));
And
protected override void OnNavigatedFrom(NavigationEventArgs e)
{
// Unregister the current page as a share source.
this.dataTransferManager.DataRequested -=
new TypedEventHandler<DataTransferManager, DataRequestedEventArgs>
(this.OnDataRequested);
}
I'd suggest doing it in the navigating events, the OnNavigatingFrom event will be triggered before the OnNavigatingTo of the page you're going to so you won't have this problem.
protected override Task OnNavigatingTo(WinRTXamlToolkit.Controls.AlternativeNavigationEventArgs e)
{
DataTransferManager.GetForCurrentView().DataRequested += dataTransfer_DataRequested;
return base.OnNavigatingTo(e);
}
protected override Task OnNavigatingFrom(WinRTXamlToolkit.Controls.AlternativeNavigatingCancelEventArgs e)
{
DataTransferManager.GetForCurrentView().DataRequested -= dataTransfer_DataRequested;
return base.OnNavigatingFrom(e);
}
//Note: This is the WinRT Xaml Toolkit version of the events, but the standard events will work the same way.