I've got the following code being called in view the viewdidload method inside of my UIViewController.
Inside the appdelegate I have a UINavigationController which is instantiated with this aforementioned controller and in turn the UINavigationController is placed inside a UITabViewController which in turn is assigned as the rootviewcontroller.
Inside the controller I'm making an async web call to get the data to populate a table, if I use the loading view code to display an activity indicator I get the following warning in monotouch.
Applications are expected to have a root view controller at the end of application launch
public class LoadingView : UIAlertView
{
private UIActivityIndicatorView _activityView;
public void ShowActivity (string title)
{
Title = title;
this.Show();
// Spinner - add after Show() or we have no Bounds.
_activityView = new UIActivityIndicatorView (UIActivityIndicatorViewStyle.WhiteLarge);
_activityView.Frame = new RectangleF ((Bounds.Width / 2) - 15, Bounds.Height - 50, 30, 30);
_activityView.StartAnimating ();
AddSubview (_activityView);
}
public void Hide ()
{
DismissWithClickedButtonIndex (0, true);
}
}
Any pointers would be gratefully received.
EDIT : I'm already setting the root view controller.
window = new UIWindow (UIScreen.MainScreen.Bounds);
window.RootViewController = tabController;
Full appDelegate code :
public override bool FinishedLaunching (UIApplication app, NSDictionary options)
{
// create a new window instance based on the screen size
window = new UIWindow (UIScreen.MainScreen.Bounds);
tabController = new UITabBarController();
jobsNavigationController = new UINavigationController(new JobsController());
jobsNavigationController.NavigationBar.BarStyle = UIBarStyle.Black;
jobsNavigationController.TabBarItem.Image = UIImage.FromFile("Images/briefcase.png");
jobsNavigationController.TabBarItem.Title = "Current Positions";
myAccountNavigationController = new UINavigationController(new LoginDialogViewController());
myAccountNavigationController.NavigationBar.BarStyle = UIBarStyle.Black;
myAccountNavigationController.TabBarItem.Image = UIImage.FromFile("images/man.png");
myAccountNavigationController.TabBarItem.Title = "My Account";
tabController.SetViewControllers(new UIViewController[] { jobsNavigationController,myAccountNavigationController,new SettingsDialogViewController()},false);
window.RootViewController = tabController;
// make the window visible
window.MakeKeyAndVisible ();
return true;
}
To avoid this warning (in iOS5) and keep iOS 4.x compatibility you can do the following inside your FinishedLaunching method:
if (UIDevice.CurrentDevice.CheckSystemVersion (5, 0))
window.RootViewController = navigation;
else
window.AddSubview (navigation.View);
Look here for a more complete sample.
window.AddSubview(tabcontroller.view);
Fixed the issue, odd I don't set the rootviewcontroller anymore.
Related
How can I disable button in MaterialAlertDialogBuilder?
I want to make similar functionality like in this screenshot:
enter image description here
I wrote the following code (dialog contains EditText where user should input his favorite food name).
final MaterialAlertDialogBuilder dialogEnterDishName = new MaterialAlertDialogBuilder(context);
//...
final EditText editTextEnterDishName = new EditText(context);
dialogEnterDishName.setView(editTextEnterDishName);
dialogEnterDishName.setPositiveButton(getString(R.string.dialog_enter_dish_name_positive_button), new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
if (!editTextEnterDishName.getText().toString().equals(""))
//...
else {
//TODO Make posititve button disabled until the user enters any character
}
}
});
//...
dialogEnterDishName.show();
}
I already knew, that class AlertDialog (MaterialAlertDialogBuilder extends AlertDialog.Builder) have a method public Button getButton(int whichButton), but I can't use it in MaterialAlertDialogBuilder.
Please, help!
Make sure that you are calling getButton() function after you inflate your AlertDialog (through .show() call). If you are doing it other way around there is no button to get.
In order to enable button back you can use TextWatcher. More details here: Android TextWatcher.afterTextChanged vs TextWatcher.onTextChanged
val customLayout = LayoutInflater.from(context).inflate(R.layout.your_alert_dialog, null, false)
val dialog = MaterialAlertDialogBuilder(context)
.setTitle("Provide name")
.setView(customLayout)
.setNeutralButton("Cancel") { dialog, _ -> dialog.dismiss() }
.setPositiveButton("Confirm") { _, _ -> }
.create()
dialog.show()
dialog.getButton(AlertDialog.BUTTON_POSITIVE).isEnabled = false
I'm trying to get the progress value of my Picture Viewer when another picture is loading. I've tried two simple ways to do it, but it didn't work out for me.
First I was using the progressProperty from the Image class:
public boolean nextImageClicked()
{
if(PICTURE_INDEX < picturePaths.size() - 1)
{
String path = picturePaths.get(PICTURE_INDEX + 1).toURI().toString();
Image newImage = new Image(path);
newImage.progressProperty().addListener((observable, oldValue, newValue) -> System.out.println("Current progress: "+newValue));
GUI.getImageView().setImage(newImage);
adjustImageViewBounds();
PICTURE_INDEX += 1;
return true;
}
else return false;
}
It didn't print out anything on the console because the progress value doesn't change bizarrely. So I've tried to put all the work stuff in a Task<Void> and getting the progress value through the Task:
public boolean nextClicked()
{
if(PICTURE_INDEX < picturePaths.size() - 1)
{
Task<Void> task = new Task<Void>()
{
#Override protected Void call() throws Exception
{
String path = picturePaths.get(PICTURE_INDEX + 1).toURI().toString();
Image newImage = new Image(path);
GUI.getImageView().setImage(newImage);
adjustImageViewBounds();
PICTURE_INDEX += 1;
return null;
}
};
task.setOnRunning(e -> System.out.println(task.getProgress()));
task.progressProperty().addListener((observable, oldValue, newValue) ->
{
System.out.println(newValue);
});
task.run();
return true;
}
else return false;
}
Also didn't work out as hoped.
task.setOnRunning(e -> System.out.println(task.getProgress()));
I implemented this to see the default value, it printed out "-1".
What have I to change to let the console return single progress values like "0.1", "0.14" ?
You need the Image to load in the background, so that the call to the constructor returns before the image is completely loaded. By default, it will block until it is loaded (so the progress property will be 1 by the time you add the listener to it):
public boolean nextImageClicked()
{
if(PICTURE_INDEX < picturePaths.size() - 1)
{
String path = picturePaths.get(PICTURE_INDEX + 1).toURI().toString();
// note additional parameter:
Image newImage = new Image(path, true);
newImage.progressProperty().addListener((observable, oldValue, newValue) -> System.out.println("Current progress: "+newValue));
GUI.getImageView().setImage(newImage);
adjustImageViewBounds();
PICTURE_INDEX += 1;
return true;
}
else return false;
}
For a Task's progress to change, you need to explicitly call updateProgress(...) on the task. The only way to know what to pass in would be to observe the image's progress and pass it to the task's progress, so you would just have a more convoluted version of the code above. This is not a good use case for a task, since Image already supports background loading out of the box.
Don't try to do this on your own. You've got no idea, how much of the image has been loaded, unless you find the size of the image before loading and load the image from a steam observing the progress of the stream, which would be unnecessarily complicated. BTW: The Image constructor you use returns when the image is completely loaded. You can specify the image to be loaded asynchronically by using the right constructor however. Image provides a progress property to observe the loading progress:
#Override
public void start(Stage primaryStage) {
ImageView iv = new ImageView();
ProgressBar pb = new ProgressBar();
Button btn = new Button("Load Image");
btn.setOnAction((ActionEvent event) -> {
// ca. 6 MB image loaded from web
Image image = new Image("http://eoimages.gsfc.nasa.gov/images/imagerecords/79000/79793/city_lights_africa_8k.jpg", true);
pb.progressProperty().bind(image.progressProperty());
iv.setImage(image);
});
ScrollPane sp = new ScrollPane(iv);
VBox.setVgrow(sp, Priority.ALWAYS);
VBox root = new VBox(btn, pb, sp);
root.setFillWidth(true);
Scene scene = new Scene(root);
primaryStage.setMaximized(true);
primaryStage.setScene(scene);
primaryStage.show();
}
I'm using the mvvm approach to develop a barcode scanning app with xamarin. The main hurdle was that the 3rd party scanner object does not work in xaml. I used a ContentPage to create a simple logic-less c# code view which allows me to have a footer with buttons and a logo overlayed at the bottom of the scanner. My problem is that could not find any great best practices for binding items from your code view to your viewModel, as opposed binding a xaml view to a viewModel. Here is some of my view below.
public class BarcodeScannerPage : ContentPage
{
ZXingScannerView zxing;
BarcodeViewModel viewModel;
public BarcodeScannerPage() : base()
{
try
{
viewModel = new BarcodeViewModel();
BindingContext = viewModel;
zxing = new ZXingScannerView
{
HorizontalOptions = LayoutOptions.FillAndExpand,
VerticalOptions = LayoutOptions.FillAndExpand,
Options = new MobileBarcodeScanningOptions
{
TryHarder = true,
DelayBetweenContinuousScans = 3000
},
ScanResultCommand = viewModel.GetResult
};
var cancelButton = new Button
{
BackgroundColor = Color.Gray,
Text = "Cancel",
TextColor = Color.Blue,
FontSize = 15,
Command = viewModel.CancelButton
};
Binding cancelBinding = new Binding
{
Source = viewModel.CancelIsAvailable,
//Path = "ShowCancel",
Mode = BindingMode.OneWay,
};
cancelButton.SetBinding(IsVisibleProperty, cancelBinding);
var doneButton = new Button
{
BackgroundColor = Color.Gray,
Text = "Done",
TextColor = Color.Blue,
FontSize = 15,
Command = viewModel.DoneButton
};
Binding doneBinding = new Binding
{
Source = viewModel.DoneIsAvailable,
//Path = "ShowDone",
Mode = BindingMode.OneWay,
};
doneButton.SetBinding(Button.IsVisibleProperty, doneBinding);
When a barcode is scanned my command, GetResultCommand, sends the result to my BarcodeView model. I have created two Bools in my BarcodeView model named isDoneAvailable and isCancelAvailable. I want to bind these values to the Visibility property of the doneButton and cancelButton in my view. Right now the buttons are bound to whatever the bool values are at the creation of BarcodeViewModel, but they DO NOT update. I need to be able to control visibility from the GetResultCommand method of my BarcodeViewModel. Specifically, when a certain number of barcodes are scanned, I want to make the buttons appear and disappear. I have a feeling they don't update because the path is not set, but when I uncomment the path, the binding doesn't work at all. Any ideas what I've done wrong with the bindings of the buttons, or the correct way to set the Path to my bools in the viewModel? Here is some of my BarcodeViewModel code below.
public class BarcodeViewModel : INotifyPropertyChanged
{
public bool CancelIsAvailable { get { return _cancelIsAvailable; } set { _cancelIsAvailable = value; OnPropertyChanged("ShowCancel"); } }
public bool DoneIsAvailable { get { return _doneIsAvailable; } set { _doneIsAvailable = value; OnPropertyChanged("ShowDone"); } }
public void OnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this,
new PropertyChangedEventArgs(propertyName));
}
}
I still would like to know the correct way to get this binding to update but, I was able to work-around this issue by creating a button in my viewModel and referencing it in my view. Then when I dynamically updated the button in my viewModel, it also updated in my view.
I am working in xamarin.forms. I am creaing an android application. In my application I have to use menu. So I took Master detail page to show the menus. And its working fine.
But my problem is before showing the Master detail page, I have to open a content page which doesn't contain the menus. So I took a content page and set it. But when I am running the application after content page, Master detail page is not appearing. The code is running successfully but the Master page is not appearing.
Can any one tell me how I can show the Master detail page after showing simple content page?
The answer will depend on if you want to maintain the navigation stack or not. If you want to add the new page to the current Navigation Stack then you need to so something like this in the Content Page:
((NavigationPage)Parent).PushAsync(newPage);
If you want to make the new page the root of the Navigation Stack then you need to do something like this:
((App) Parent).MainPage = newPage;
If this doesn't work, post your code.
Giving you a trick ! suppose you have a login page ,after authentication you will go to RootPage which is a masterDetailPage .
Take a hint from from below code
namespace LoginNavigation
{
public class App : Application, IloginInterface
{
public static App current;
public static bool IsUserLoggedIn { get; set; }
public static double ScreenWidth;
public static double ScreenHeight;
public App () {
current = this;
MainPage = new LoginPageWithStack ();
}
public void Logout() {
MainPage = new LoginPageWithStack ();
}
public void ShowMainPage() {
MainPage = new RootPage ();
}
}
}
rootPage:
namespace LoginNavigation
{
public class RootPage:MasterDetailPage
{
MenuPage menuPage;
public RootPage () {
ToolbarItems.Add(new ToolbarItem("Filter", "ring.png", async () => {
var page = new ContentPage();
var result = await page.DisplayAlert("Title", "Message", "Accept", "Cancel");
Debug.WriteLine("success: {0}", result);
}));
menuPage = new MenuPage ();
menuPage.Menu.ItemSelected += (sender, e) => NavigateTo (e.SelectedItem as MenuItemForMaster);
//Master = new MasterMenu();
Master = menuPage;
Detail = new NavigationPage (new TimeSheet()){
BarBackgroundColor = Color.FromHex("008dce"),BackgroundColor = Color.FromHex("008dce")
};
}
void NavigateTo (MenuItemForMaster menu) {
if (menu == null)
return;
Page displayPage = (Page)Activator.CreateInstance (menu.TargetType);
//Detail = displayPage;
Detail = new NavigationPage (displayPage) { BarBackgroundColor = Color.FromHex("008dce"),BackgroundColor = Color.FromHex("008dce")};
menuPage.Menu.SelectedItem = null;
IsPresented = false;
}
}
}
So the trick is ,get the current instance of App class and manipulate Mainpage property of it .
From the examples at Xamarin.com you can build basic M.T. Dialog apps, but how do you build a real life application?
Do you:
1) Create a single DialogViewController and tree every view/RootElement from there or,
2) Create a DialogViewController for every view and use the UINavigationController and push it on as needed?
Depending on your answer, the better response is how? I've built the example task app, so I understand adding elements to a table, click it to go to the 'next' view for editing, but how to click for non-editing? How to click a button, go next view if answer is number 1?
Revised:
There is probably no one right answer, but what I've come up with seems to work for us. Number 2 from above is what was chosen, below is an example of the code as it currently exists. What we did was create a navigation controller in AppDelegate and give access to it throughout the whole application like this:
public partial class AppDelegate : UIApplicationDelegate
{
public UIWindow window { get; private set; }
//< There's a Window property/field which we chose not to bother with
public static AppDelegate Current { get; private set; }
public UINavigationController NavController { get; private set; }
public override bool FinishedLaunching (UIApplication app, NSDictionary options)
{
Current = this;
window = new UIWindow (UIScreen.MainScreen.Bounds);
NavController = new UINavigationController();
// See About Controller below
DialogViewController about = new AboutController();
NavController.PushViewController(about, true);
window.RootViewController = NavController;
window.MakeKeyAndVisible ();
return true;
}
}
Then every Dialog has a structure like this:
public class AboutController : DialogViewController
{
public delegate void D(AboutController dvc);
public event D ViewLoaded = delegate { };
static About about;
public AboutController()
: base(about = new About())
{
Autorotate = true;
about.SetDialogViewController(this);
}
public override void LoadView()
{
base.LoadView();
ViewLoaded(this);
}
}
public class About : RootElement
{
static AboutModel about = AboutVM.About;
public About()
: base(about.Title)
{
string[] message = about.Text.Split(...);
Add(new Section(){
new AboutMessage(message[0]),
new About_Image(about),
new AboutMessage(message[1]),
});
}
internal void SetDialogViewController(AboutController dvc)
{
var next = new UIBarButtonItem(UIBarButtonSystemItem.Play);
dvc.NavigationItem.RightBarButtonItem = next;
dvc.ViewLoaded += new AboutController.D(dvc_ViewLoaded);
next.Clicked += new System.EventHandler(next_Clicked);
}
void next_Clicked(object sender, System.EventArgs e)
{
// Load next controller
AppDelegate.Current.NavController.PushViewController(new IssuesController(), true);
}
void dvc_ViewLoaded(AboutController dvc)
{
// Swipe location: https://gist.github.com/2884348
dvc.View.Swipe(UISwipeGestureRecognizerDirection.Left).Event +=
delegate { next_Clicked(null, null); };
}
}
Create a sub-class of elements as needed:
public class About_Image : Element, IElementSizing
{
static NSString skey = new NSString("About_Image");
AboutModel about;
UIImage image;
public About_Image(AboutModel about)
: base(string.Empty)
{
this.about = about;
FileInfo imageFile = App.LibraryFile(about.Image ?? "filler.png");
if (imageFile.Exists)
{
float size = 240;
image = UIImage.FromFile(imageFile.FullName);
var resizer = new ImageResizer(image);
resizer.Resize(size, size);
image = resizer.ModifiedImage;
}
}
public override UITableViewCell GetCell(UITableView tv)
{
var cell = tv.DequeueReusableCell(skey);
if (cell == null)
{
cell = new UITableViewCell(UITableViewCellStyle.Default, skey)
{
SelectionStyle = UITableViewCellSelectionStyle.None,
Accessory = UITableViewCellAccessory.None,
};
}
if (null != image)
{
cell.ImageView.ContentMode = UIViewContentMode.Center;
cell.ImageView.Image = image;
}
return cell;
}
public float GetHeight(UITableView tableView, NSIndexPath indexPath)
{
float height = 100;
if (null != image)
height = image.Size.Height;
return height;
}
public override void Selected(DialogViewController dvc, UITableView tableView, NSIndexPath indexPath)
{
//base.Selected(dvc, tableView, path);
tableView.DeselectRow(indexPath, true);
}
}
#miquel
The current idea of a workflow is an app that starts with a jpg of the Default.png that fades into the first view, with a flow control button(s) that would move to the main app. This view, which I had working previous to M.T.D. (MonoTouch.Dialog), which is a table of text rows with an image. When each row is clicked, it moves to another view that has the row/text in more detail.
The app also supports in-app-purchasing, so if the client wishes to purchase more of the product, then switch to another view to transact the purchase(s). This part was the main reason for switching to M.T.D., as I thought M.T.D. would be perfect for it.
Lastly there would be a settings view to re-enable purchases, etc.
PS How does one know when the app is un-minimized? We would like to show the fade in image again.
I have been asking myself the same questions. I've used the Funq Dependency Injection framework and I create a new DialogViewController for each view. It's effectively the same approach I've used previously developing ASP.NET MVC applications and means I can keep the controller logic nicely separated. I subclass DialogViewController for each view which allows me to pass in to the controller any application data required for that particular controller. I'm not sure if this is the recommended approach but so far it's working for me.
I too have looked at the TweetStation application and I find it a useful reference but the associated documentation specifically says that it isn't trying to be an example of how to structure a MonoTouch application.
I use option 2 that you stated as well, it works pretty nicely as you're able to edit the toolbar options on a per-root-view basis and such.
Option 2 is more feasible, as it also gives you more control on each DialogViewController. It can also helps if you want to conditionally load the view.