I made an andorid application using the "activity" component. I used it for a while, but over time I found that one page was not enough for me. I needed to add tabLayout, viewPager2 and three fragments.
I needed to migrate the functionality from mainActivity to the firstFragment.
I encountered a problem with events during the XML migration. In the activity I called android: onClick = "myOnClicFunction". But is that not possible?
I know that this has been discussed several times here in several threads. However, I would like to ask how to proceed correctly.
Here in the thread Android Fragment onClick button Method is the advice "even if you are in the fragment, put the onClick functions into activity" there is another similar advice to, "if you insist to make it in a fragment"
But what is right? Should the onclick function be correct in the activity or in the fragment?
I don't want to put the source code here, because I don't know which procedure is correct at all.
I am creating a program that is for testing students. An example is displayed and a response is pending.
The first tab has a lot of buttons + saves the result to an xml files.
The second tab will contain statistics. From saved files displays how many calculations were correct, wrong, average response time, etc ...
In Activity I had functions like getQuestion(), evaluateQuestion(), saveToXml() and events zeroWasPressed(), oneWasPressed(), twoWasPressed(), threeWasPressed() ...
Where should I put all these functions when I change the application from Activity to Fragment?
on click function listener should be placed in corresponding fragment, where the button is added in fragment layout.
events zeroWasPressed(), oneWasPressed(), twoWasPressed(), threeWasPressed() ... should be placed inside corresponding fragment where those buttons were added in layout.
getQuestion(), evaluateQuestion(), saveToXml() , this function can be placed in your activity or some other custom classes, that would appropriate according to architecture viewpoint.
Related
I recently refactored half my app to use the provider pattern and i now have a problem. The main issue is that i need to initialise controllers in the init (e.g. a text controller to have an initial value or the list size of a tab controller)
How am i meant to init Controllers if the data i need has to come from the state in the build method.
For example.
// This must go in the build as it requires state
myTabsController = TabController(length: myState.list.length, vsync: this);
I'm initialisng the controller every time it builds now... How am i meant to put this in the init but still access the state variables (as there is no context).
I've tried using the afterFirstLayout() callback from the AfterLayoutMixin library but that just causes more problems. Currently with the tab bar it flashes error as no tab initialised for the first frame and then displays properly when the afterFirstLayout is called and initialises the tab. This seems like a hacky fix
I would like to learn more about how to use this pattern properly and what would be the best solution to this problem.
Feel free to ask me to clarify more.
Thanks for your help.
So I'm trying to build my own custom view for a month's worth of data (based on the "agenda-views.html' example) and I've been able to create a custom View class which adds itself as a button on the list of .. buttons.
When I click on that button (MyView), its setRange is called so I know the range of Events to display.
The View's renderEvents is called but is passed all of the Events that the Calendar knows about, so I have a two parter question:
(a) Is there a way I can use existing code to do the equivalent of: "given this range, give me all of the Events fullCalendar knows about"?
- or -
(b) Do I use an XHR here to pull back the data for the given range (now that I know what it is is) and Render it
I'd rather do (a) as it's more efficient (less requests etc) but I'm finding myself swamped in code and, after reading through quite a lot it haven't really found a method that says 'Get all events for this range'.
Alternatively, am I missing something? How does renderEvents know what the current range is and then render them? Or, should I be using renderSelection, which doesn't seem to get called.
Thanks!
Set up your events as a json feed, when the URL is called it will pass the start and end dates for the current view. In your function/method/action you then retrieve your events for the given dates and return them.
I may have worked myself into a corner but this sounded to me like a good idea at the time.
I have been developing an interface that permits a user to modify settings of a robotic device, i.e. speed, directions, force, etc. with a very large series of options in the form of ComboBoxes. The problem is that there are about a thousand of these things, in sub categories. e.g. Speed category x1, x2, x3, Y1, y2, etc. So rather than create a thousand comboboxes in QT, I thought the good idea was to create one set of 50 (ish) and then provide a few button to switch between categories. So when the user selects speed QT, populates the comboboxes with the appropriate options, sets the style sheets and text for the labels etc. So it appears as though a dedicated page exists. Then if the user selects Direction, QT Writes the current index of each box to a dedicated array and then repopulates the boxes, labels etc with the appropriate content. I then do this over and over for the various needs of the system.
All of that seems to work fine. However I am now in a bind where the options provided to navigate to each page have grown. For instance I have forward / backward buttons (like you woudl expect in a set-up wizard), as well as action menus at the top to jump to a page. So now the code is becoming very repetitious. If you select the next button, I write the current values to array, then repopulate. If you jump to the page from anywhere, I look to see where I am, write it to array, and populate the boxes. Thus if I need to change anything I have to make the change in numerous places in the code.
I know that this is not optimal. What I woudl like to do is run a continuous loop as I woudl normally do with Micros in C. So the program can look at a variable in each pass and if it is then it does. I am not however skilled enough to figure this loop out in QT. So my new thought was...
Is it possible to trigger an action or slot with a variable. For example, if the user presses the Next button it triggers a slot for a button that does not exist, so that QT will execute a particular line of Code? Then I can have 1 dedicated section focused on reading and writing boxes, with a bunch of actions that will take me there.
You can make a signal that is triggered with an emit call in your code, so you'd hook up the next button signal of clicked to a slot that does some work and moves on, or directly calls another signal that you've created that triggers a slot elsewhere, or do some work in a lambda triggered by the button press.
I would first load all the ComboBoxes options in a QStringList array (or maybe an array of QList<QLatin1String> lists - for memory saving and code efficiency).
Then I would keep an array of a 1000 integers for current ComboBox indexes.
When the user changes a value in some ComboBox, the currentIndexChanged signal will trigger the corresponding slot (a single slot for all the ComboBoxes would be enough - sender()->objectName() to get the name of the ComboBox which had sent the signal):
void WindowWidget::on_ComboBox_currentIndexChanged(int index)
{
name = sender()->objectName();
/* here change the corresponding integer in the current
indexes array */
}
On Next/Back button push repopulate the ComboBoxes. Also, provide some 'Save' button for saving the ComboBoxes indexes (or trigger the Save slot on some action, i.e. on window close either even on a timer signal).
Per Active reports documentation, the Report start is called first and Data initialize. Any reference to Data source inside Report start will invoke Data Initialize event. I am modifying an existing report; and to my surprise the order is reversed. I have an existing logic to get the count of nodes (my datasource is xml) in data initialize event; just because the event firing sequence is reversed, I am getting 0 as count always.
I am using Active reports for .NET 2.0 ( I think the version is 4.*). As I dont have support for the designer, I have the designer xml and code behind.
Please suggest what could force the event sequence to correct order.
There is probably not enough information for us to help you here. We'd need to see the report code at least, but better if you can do some debugging to find out more detail about what specific code you have that is causing the trouble.
I'm actually not sure about event order in this specific case, but to troubleshoot you could try with a new blank report to verify the event order in that case and move over one piece of code at a time to find out which line of code causes the event order to change.
Im wondering how to implement undo redo functionality with a TextArea. I already have an undoredo framework functionality working, now I have two questions.
When do I start/stop a new undo/redo command, eg when a user hits undo, how far back do I go.
How do I implement this(1.) in a normal TextArea
My thinking:
I thinking that I should create a new undo command, when anything but a alphanumber+space is hit. To do this I would use the keyDown event and test if the key is alpha num if it is not I will reset the command.
Sound good?
Listening for keydown events would miss any text editing that user does with the mouse (cut/copy/paste).
I think a better approach would be to listen for 'change' event on the control (which fires whenever the content changes through user input), and just push the full content of the control (its 'text' or 'htmlText' attribute) with every change event into a undo-buffer (an Array of Strings). I assume that the memory usage is not an issue (it probably isn't, depending on the expected size of the controls content and number of undo levels).
This way, you implement undo/redo just by copying the corresponding control state (moving up and down through array, basically) in the undo buffer back into the control.
The 'proper' approach would be to track the actual edits, and would be condsiderably more complicated.
1.When do I start/stop a new undo/redo command, eg when a user hits undo, how far back do I go.
Do you think your users will need to undo multiple steps? If so, then you may want to have a history (e.g. Paint .NET) and allow infinite undo-s. Otherwise, just remember the most recently performed action.
1.) You should listen for the Event.CHANGE event on the TextField and create a history step each time the event is fired. A history step consists in your case of two values: old and new.
Old is the value of the TextField before change, new is its value after the change.
2.) Your history is a sequence of actions or you can use the Memento Pattern. I think actions are much easier to use. A history action has two methods, undo() and redo(). So in undo() you have to say textField.text = oldContent and in the redo() method you say textField.text = newContent. Your history will also need a pointer to the current action.
3.) To make it a little bit better. You should not listen only for Event.CHANGE but instead listen for the first CHANGE and then the next FOCUS_OUT for that TextField. In that case, a history step is only created once I stop editing the TextField. But it depends on your TextField and how you want to distribute history steps. A multiline TextField should not create a history step only on FOCUS_OUT :)