I am getting NullPointerException in the code for contextmenu.
here is the onCreateContextmenu Method
public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
menu.add(0, MENU_EDIT, 0, "Edit");
menu.add(0, MENU_DELETE, 0, "Delete");
}
I am getting the error in the line long buttonId = info.id; in the code below
public boolean onContextItemSelected(MenuItem item) {
AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
long buttonId = info.id;
switch (item.getItemId()) {
case MENU_EDIT:
function1(buttonId);
break;
case MENU_DELETE:
function2(buttonId);
break;
}
return true;
}
Can some one help me fix this
view isn't passed to onContextItemSelected and
AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
long buttonId = info.id;
This code doesn't help because menuInfo is null when view is a button. The Android doc says "menuInfo Extra information about the item for which the context menu should be shown. This information will vary depending on the class ofv". When v is a ListView menuInfoapproach is fine. When it is a Button, it doesn't work.
In onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo), the View v is the button that produced the context menu. Copyv to a global View varaiable and use that where you need to have the view of the button that produced the context menu.
How to get the Button view which triggered a Context Menu?
Related
I want to remove Tabbar from TabbedPage. I got it working but it leaves blank space or page height is not updated after hiding Tabbar.
Note that when we swipe through the pages, the blank goes and never comes back. This issue appears only for the first time.
I have tried from this link. But it doesn't work.
Also tried following
private void Element_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
{
try
{
TabBar.Hidden = true;
//TabBar.Bounds = new CoreGraphics.CGRect(View.Subviews[0].Frame.X, View.Subviews[0].Frame.Y,
// View.Subviews[0].Frame.Width, 0);
if (TabBar.Hidden)
{
// page
View.Subviews[0].Frame = new CoreGraphics.CGRect(0, 0, View.Subviews[1].Frame.Width, NativeView.Frame.Height);
// Tabbar
View.Subviews[1].Frame = new CoreGraphics.CGRect(View.Subviews[0].Frame.X, View.Subviews[0].Frame.Y,
View.Subviews[0].Frame.Width, 0);
}
else
{
View.Subviews[1].Frame = new CoreGraphics.CGRect(View.Subviews[1].Frame.X, View.Subviews[1].Frame.Y,
View.Subviews[1].Frame.Width, 49);
View.Subviews[0].Frame = new CoreGraphics.CGRect(View.Subviews[0].Frame.X, View.Subviews[0].Frame.Y,
View.Subviews[0].Frame.Width, View.Subviews[0].Frame.Height - 49);
}
//if (TabBar.Hidden)
// View.Subviews[1].Frame = new CoreGraphics.CGRect(View.Subviews[1].Frame.X, View.Subviews[1].Frame.Y, View.Subviews[1].Frame.Width, 0);
//else
// View.Subviews[1].Frame = new CoreGraphics.CGRect(View.Subviews[1].Frame.X, View.Subviews[1].Frame.Y, View.Subviews[1].Frame.Width, 49);
}
catch (Exception ex)
{
//TraceLog("Element_PropertyChanged" + ex.Message);
}
}
EDIT
I open tabbed page on list view item clicked. I allow to add multiple tabs dynamically. Also I have created custom tabbar using ContentView that I update when pages are added or removed from TabbedPage.
The sequence is :
- User opens first tab.
- Click on home icon given on tabbed page.
- open the second page by click on another list item
- swipe through the page and the page height will be normal.
Here is the code on ListView_ItemTapped (Not posted exactly how is it actually but you can get idea :) )
MultiTab ObjMultiTab = new MultiTab(); // Initialize tabbed page
// Get data from server
ObjMultiTab.Data = ObjData;
int Id = Convert.ToInt32(ObjData.id);
if (ActiveList.ContainsKey(Id)) // Dictionary that contains info about index and pageid that are already open
{
TabId = ActiveList[ObjData.id];
CurrentPage = Children[TabId]; // If user taps on already opend page
}
else
{
Count += 1; ActiveList.Add(Id, Count);
Children.Add(new SecondTabbedPage(TableData)); // Or add new child
CurrentPage = Children[Count];
}
await Application.Current.MainPage.Navigation.PushModalAsync(ObjMultiTab);
Is there any way to remove blank space for the first time also ?
Adding following function to the renderer removed blank space from TabbedPage.
public override void ViewDidLayoutSubviews()
{
base.ViewDidLayoutSubviews();
TabBar.Hidden = true;
var page = View.Subviews[0];
var tabbar = View.Subviews[1];
tabbar.Bounds = CGRect.Empty;
page.Bounds = UIScreen.MainScreen.Bounds;
}
There is a solution that doesn't require any renders and works on both Android and iOS.
Wrap the TabbedPage in a NavigationPage so the structure of your app becomes
NavigationPage (root)
TappedPage
NavigationPage
ContentPage (with tabbar)
ContentPage (without tabbar)
On the TabbedPage you have to hide the navigationbar of the 'root' NavigationPage, otherwise you have 2 navbars.
<TabbedPage
...
HasNavigationBar="False">
If you push a page using the 'root' NavigationPage, the tabbar is hidden and there is no blank space at the bottom.
--- Edit ---
See my example at:
https://github.com/Jfcobuss/HideTabbarExample/tree/master/HideTabbarExample
Downside of this solution is
It is bit of an hacky workaround
The title next to back-button is the title of the TabbedPage, not the current tab
The animation to the next page is not as fluent as default
I have manually/programmatically set up an up button in my toolbar for a fragment page with the following code in onCreateOptionsMenu in the fragment:
(activity as AppCompatActivity).setSupportActionBar?.setDisplayHomeAsUpEnabled(true)
Tapping the system back button will take the user back to the previous fragment but without an up button (that works) I think some users may get lost.
I am having difficulty trying to work out how to catch and handle the up button to pop the fragment off the back stack.
This SO post shows how to catch the the up button click however it is in Java and doesn't go on to explain how you would navigate up.
I think it needs to look something like the code below but there are errors everywhere:
The case android.R.id.home is showing an 'Incompatible types:Int and MenuItem' error?
onBackPressed() is showing an 'Unresolved reference' error.
Bad code:
override fun onOptionsItemSelected(item: MenuItem?): Boolean {
when (item) {
android.R.id.home -> {
onBackPressed()
return true
}
else -> return super.onOptionsItemSelected(item)
}
}
UPDATE:
A comment to another SO post has a potential solution in Kotlin. It catches the click on the up button and goes back to the previous fragment page but then the up button doesn't go away. So the up button now persists even on the top level fragment destinations in my app (the pages corresponding to each tab in the BottomNavigationView).
I think this might have to do with the fact that there is only one activity in my app and the way that I have set up the up button in the fragment as mentioned above? If so, is there a workaround or other way to set up the up button by referencing the fragment instead of the whole activity?
If it helps, this is the code in the RecyclerView inner ViewHolder class in the adapter.kt file that navigates to the fragment page in question:
class AdapterListItemDetails(val items: List<ItemsList>) : RecyclerView.Adapter<AdapterListItemDeatils.ItemsViewHolder>() {
//overrides for OnCreateViewHolder, getItemCount, onBindViewHolder
inner class ItemsViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
var currentItem: ItemsList? = null
var currentPosition: Int = 0
init {
itemView.setOnClickListener(Navigation.createNavigateOnClickListener(R.id.goto_details, null))
}
fun setData(itemsList: ItemsList, position: Int) {
itemView.tview_Keys.text = itemsList!!.nameText
this.currentItem = itemsList
this.currentPosition = position
}
}
}
You have to override onBackPressed() method in activity and handle the fragment transactions with your manual code. If you could share some snippet of activity and fragment transactions will help me to give some proper solution.
Hi this is what i usually do:
in an activity find the navController from your navHostFragment
val navController = this.findNavController(R.id.myNavHostFragment)
Make sure it's connected to the ActionBar
NavigationUI.setupActionBarWithNavController(this, navController)
Then simply override onSupportNavigateUp, find your navController then navigate up
override fun onSupportNavigateUp(): Boolean{
val navController = this.findNavController(R.id.myNavHostFragment)
return navController.navigateUp()
}
I have a form in my Xamarin project that its result is something like that:
Basically there is a header (1) and a body of this form (2). The header is quite simple build with AbsoluteLayout.
For creating the body (2) I've created my component to show a tab control and then for each tab a specific grid with images and text. For each section, I'm checking in the database how many records there are for it and change the text. This activity is very long and I'm trying to understand why and how I can improve speed.
Then I should cut the corner to add later in my page the tab control so the user can see immediately the header and after few second all page. The code is like the following:
public class MyPage : WaitingPage
{
public MyPage(Card card)
{
LoadingMessage = "Loading...";
ShowLoadingFrame = true;
ShowLoadingMessage = true;
ShadeBackground = true;
WaitingOrientation = StackOrientation.Vertical;
IsWaiting = true;
StackLayout stackPage = new StackLayout() {
BackgroundColor = Color.FromHex("#fff"),
Children = {
ShowHeader(card),
}
};
Content = stackPage;
Task.Yield();
Task.Run(async () => {
Content = await ShowDetails(card);
});
IsWaiting = false;
}
}
I tried different ways to add the content from await ShowDetails(card); but nothing happens. Basically the content doesn't change unless await ShowDetails(card); is executed. I discovered Task.Yield(); (you can wait the page is rendered and showed and then continue) but in this case doesn't work. And also WaitingPage doesn't show the message.
Any suggestions or help? Thank you in advance
I'm trying to use a flexlib schedule viewer in my application.
I want to have it so that when I click on a scheduled event, it calls a function in my main app (that will allow me to edit the event). But there doesn't seem to be any specific function for anything like this built into the class ie no event dispatched when I click on an event.
I can use the 'click' function to detect that the item has been clicked on.. and have tried something like this:
private function exerciseClickHandler(event:MouseEvent):void{
if (exerciseSeries.selectedItem != null){
//code
}
}
<code:ScheduleViewer id="exerciseSeries" click="exerciseClickHandler(event)" />
This method isn't very reliable because if it only works the first time.. once an item is selected, it stays selected so all following clicks on the item fulfills the condition.
Is there any way to determine whether an event was being clicked on?
Or do I have to extend the component and add some sort of clickEvent when an event is clicked on.
Since exerciseClickHandler is firing up when you click on the component, wouldn't this work?
Instead of
private function exerciseClickHandler(event:MouseEvent):void{
if (exerciseSeries.selectedItem != null){
//code
}
}
write
private function exerciseClickHandler(event:MouseEvent):void{
switch (exerciseSeries.selectedItem)
{
//code
case xy:
break;
}
}
or
private function exerciseClickHandler(event:MouseEvent):void{
//do something with exerciseSeries.selectedItem
}
What I mean is that you wrote that everything stops after the first element is clicked. And according to the code you provided it has to stop, beacuse after the first click exerciseSeries.selectedItem won't be null anymore, since it's selected. So remove the conditional you wrote and use the instance.
I'd suggest you set up a ChangeWatcher to keep an eye on the selectedItem (or selectedItems if you are going to allow multiple selection at some point). Example:
protected exerciseSeriesCreationCompleteHandler(event:FlexEvent):void{
ChangeWatcher.watch(this,['exerciseSeries','selectedItem'], handleChange_SelectedItem);
}
protected function handleChange_SelectedItem(event:PropertyChangeEvent):void{
// Either
dispatchedEvent(//some custom event);
// Or
someDirectMethodCall();
}
An alternative would be to search for an instance of the the event class in the view hierarchy under the mouse coordinates whenever a user clicks.
//Attach this click handler to the component
private function handleClick(event : MouseEvent) : void {
var obj : *EventClass*= null;
var applicationStage : Stage = FlexGlobals.topLevelApplication.stage as Stage;
var mousePoint : Point = new Point(applicationStage.mouseX, applicationStage.mouseY);
var objects : Array = applicationStage.getObjectsUnderPoint(mousePoint);
for (var i : int = objects.length - 1; i >= 0; i--) {
if (objects[i] is *EventClass*) {
obj = objects[i] as *EventClass*;
break;
}
}
if(obj is *EventClass*){
//Dispatch some custom event with obj being the item that was clicked on.
}
}
Where EventClass is the class of the objects that represent events
I have had similar problems and sometimes you can get by with wrapping the object with a Box and putting the click event on the Box. If you have not already tried that, it's a cheap, easy fix (if it works for you).
<mx:Box click="exerciseClickHandler(event)">
<code:ScheduleViewer id="exerciseSeries" />
</mx:Box>
I need to programmatically remove an alert.
This is why:
My application uses BrowserManager to enable deep linking based off of the content in the #hash part of the url. If an alert is currently up, and the user hits the back button, the application will revert back to its previous state. But the Alert will still be up, and in many cases irrelevant at that point.
So is there a way to programmatically remove the Alert? so when the hash fragment changes I can remove it.
Thanks!
It turns out the Alert.show function returns an Alert reference and then just uses PopUpManager to add it to the display list. so if you capture the return reference when you call Alert.show you can tell PopUpManager to remove it. :)
You can do this by keeping the Alert object as member data, and then setting its visible property to false when you're done with it. Next time you need to show an Alert, don't create a new one - grab the one you've already created and set its properties, then set visible to true again.
private var myAlert : Alert;
public void showAlert( message: String, title : String ) : void
{
hideAlert();
myAlert = Alert.show( message, title, Alert.OK | Alert.NONMODAL );
}
public void hideAlert() : void
{
if( myAlert != null && myAlert.visible ) {
myAlert.visible = false;
}
}
I don't think that is possible.
You can create your own alert component subclassing TitleWindow and then use PopupManager to show/hide them.