Develop Reference

Insert icon in a tabbed page(Android) on xamarin form

I'm new to StackOverflow community!
I need help with one problem with android in Xamarin Forms. To be precise... I tried with some friends to build our first app. We choose(with the help of our University professor) Xamarin for the cross-platform development of Android and iOS for both systems using the Xamarin Forms. I created the interface part of the app and now I am stuck in a fort with big walls. When I try to add a Tabbed Page the icon for the functional bar, the app crashes(Android) but in iOS, the problem doesn't appear...
I'd try with some solution... like :
-Render in the NameApp.Droid adds different renderer only for the android part but no result...
-Try another way to insert the icon in the .xaml file directly but no result...
-Try to follow another way to modify the .axam file for the "Theme" part
but no result...
I want to integrate all the stuff on time only in the "Main Project". I don't want for now touch the "nameProject.Droid" or "nameProject.iOS" part, But try to make in one shoot both(Andriod & iOS). I've found a different bug in Android (è.é) but for this, I am going crazy...
But I need to modify the ".Droid" no problem I accept the challenge!
This is the result I aspire to create.
"https://storage.googleapis.com/material-design/publish/material_v_12/assets/0B6Okdz75tqQsbHJuWi04N0ZIc0E/components-tabs-usage-mobile7.png"
This is the way I add the Icon in the Tabbed Page. An assumption I add all the stuff in the "Resource" in ".Droid" and ".iOS :
var MainPageTabbed = new MPageTabbed();
var Profile = new Profile();
var ListChat = new ListChat();
if (Device.RuntimePlatform == Device.Android)
{
MainPageTabbed.Icon = "ldpi.png";
Profile.Icon = "ldpi2.png";
Chat.Icon = "ldpi1.png";
}
if (Device.RuntimePlatform == Device.iOS)
{
MainPageTabbed.Icon = "ldpi.png";
Profile.Icon = "ldpi2.png";
ListChat.Icon = "ldpi1.png";
}
NavigationPage.SetHasNavigationBar(this, false);
Children.Add(MainPageTabbed);
Children.Add(Profile);
Children.Add(ListChat);
Someone can help me please to find a solution?

Here you have an example of how to use the TabbedPage in xamarin forms:
https://developer.xamarin.com/guides/xamarin-forms/application-fundamentals/navigation/tabbed-page/
... Xamarin.forms renders Android tabbed-pages as something called a viewpager combined with a TabPagerStrib, and it looks like the example in the link above.
You might read about BottomNavigationBar for Android instead, or look at this link for a TabPagerStrip with an image:
https://forums.xamarin.com/discussion/39937/adding-icons-to-a-pagertabstrip-instead-of-text

If anyone is interested in a FontAwesome custom icon implementation I followed this tutorial to begin with: FontAwesome with Xamarin Forms
Unfortunately he doesn't give an example of integrating with tabbed pages but after some experimenting I finally figured out a simplified Xaml way to render it without a custom tabbed renderer:
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:local="clr-namespace:IBMobile.Views"
xmlns:local2="clr-namespace:FontAwesome"
x:Class="IBMobile.Views.HomePage"
Visual="Material">
<ContentPage.IconImageSource>
<FontImageSource FontFamily="{StaticResource FontAwesomeSolid}" Glyph="{x:Static local2:IconFont.Home}" />
</ContentPage.IconImageSource>

Taking Screenshots Using Qt C++ on Android

thanks for checking my question out!
I'm currently working on a project using Qt C++, which is designed to be multi-platform. I'm a bit of a newcoming to it, so I've been asked to set up the ability to take screenshots from within the menu structure, and I'm having issues with the Android version of the companion app.
As a quick overview, it's a bit of software that send the content of a host PC's screen to our app, and I've been able to take screenshots on the Windows version just fine, using QScreen and QPixmap, like so:
overlaywindow.cpp
{
QPixmap screenSnapData = screenGrab->currentBackground();
}
screenGrabber.cpp
{
QScreen *screen = QGuiApplication::primaryScreen();
return screen->grabWindow( QApplication::desktop()->winId() );
}
Unfortunately, Android seems to reject QScreen, and with most suggestions from past Google searches suggesting the now-deprecated QPixmap::grab(), I've gotten a little stuck.
What luck I have had is within the code for the menu itself, and QWidget, but that isn't without issue, of course!
QFile doubleCheckFile("/storage/emulated/0/Pictures/Testing/checking.png");
doubleCheckFile.open(QIODevice::ReadWrite);
QPixmap checkingPixmap = QWidget::grab();
checkingPixmap.save(&doubleCheckFile);
doubleCheckFile.close();
This code does take a screenshot, but only of the button strip currently implemented, and not for the whole screen. I've also taken a 'screenshot' of just a white box with the screen's dimensions by using:
QDesktopWidget dw;
QWidget *screen=dw.screen();
QPixmap checkingPixmap = screen->grab();
Would anyone know of whether there was an alternative to using QScreen to take a screenshot in Android, or whether there's a specific way to get it working as compared to Windows? Or would QWidget be the right track? Any help's greatly appreciated!

as i can read in Qt doc : In your screenGrabber.cpp :
QScreen *screen = QGuiApplication::primaryScreen();
return screen->grabWindow( QApplication::desktop()->winId() );
replace with :
QScreen *screen = QGuiApplication::primaryScreen();
return screen->grabWindow( 0 ); // as 0 is the id of main screen

If you want to take a screenshot of your own widget, you can use the method QWidget::render (Qt Doc):
QPixmap pixmap(widget->size());
widget->render(&pixmap);
If you want to take a screenshot of another app/widget than your app, you should use the Android API...

Show image in TImage dynamically (at run time) without opendialog in c++ builder xe8

I want to show image (png,jpg etc) in dynamically created (as per requirement and fully through coding) TImage component, at runtime in C++ builder xe8 (not delphi). But I dont want to use opendialogbox (suggested in many web sites). I want to run this app on my android device. I tried to use LoadFromFile(), it crashes the app on android, but when I run this on windows, its running smoothly. I am just a beginner to c++ builder. So guys pls help. Thanx in advance for any kind of help.Here is what I did.
void __fastcall TForm1::TForm1(TComponent* Owner)
{
TImage* img = new TImage(this);
img->Parent = this;
img->Bitmap->LoadFromFile("D:\\res\\profile.png");
}

Did you see what is the error?
If you run the program with the provided by you code I assume the error would be that the file is not found, because there is no such directory "D:\" in android.
One way to set the path is to write a static path which points to your image. For example : "/storage/sdcard0/DCIM/Camera/MyImage.jpg";
The second way is to include the <System.IOUtils.hpp> header and to use some built-in functions like:
System::Ioutils::TPath::GetPicturesPath();
System::Ioutils::TPath::GetAlarmsPath();
You can check them out, they might be useful.

How to import a SpriteFont into MonoGame

I'm porting a simple tetris-like XNA app to Android, using Mono For Android and MonoGame; I have followed the suggested steps in this link and so far, everything compiles well, and no relevant warnings fire up. However, upon loading the contents, a null parameter exception breaks the program at the point below in my program:
protected override void LoadContent() {
// ...
_font = Content.Load<Microsoft.Xna.Framework.Graphics.SpriteFont>("SpriteFont1");
// ...
}
The content root directory is set in the game constructor class:
public Game2 (){
Content.RootDirectory = "Content";
Content.RootDirectory = "Assets/Content"; // TEST.
//...}
And I have tried several combinations, all to no avail.
I have also tried setting the xnb files as Content as well as Android Assets in the Build Action property; having the linked, copied always, copied only if newer... etc.
Either way, my problem is that I don't really understand WHY and HOW should I do this. I'm rather new to the platform and to XNA as well, so this may very well be a newbie question, but the truth is after several hours banging my head and fists against the monitor/keyboard I feel stuck and need your help.

I have a library that supports variable-width fonts (generated by BMFont) on MonoGame. Unfortunately it is a renderer and so has other code around it. However, the basic idea is very simple. You can take a look at the loader here and the mesh builder (given a string) here. This builder supports fonts that spread characters across multiple pages, too.
Hope this helps!

MonoGame (2.5.1) throws NotImplementedException in ContentManager.Load for SpriteFont type. Have the same not resolved problem. I'm trying not to use DrawString.
For loading textures in Win32 application I use:
Content.RootDirectory = #"../../Content";
var sampleTexture = Content.Load<Texture2D>("Sample.png");
You even must not add it to solution.
For Andoind (MonoDroid) application you must add "Content" folder to your solution and set "Andtoid Asset" in "Sample.png" properties.
Content.RootDirectory = "Content";
var sampleTexture = Content.Load<Texture2D>("Sample.png");
See also:
http://monogame.codeplex.com/discussions/360468
http://monogame.codeplex.com/discussions/267900

image won't show in tableView

I'm creating a tableView in appcelerator (Android) and I want to add an image to it. This is just a test because I also had some problems with it in my project and I wanted to try it out first somewhere else so I wouldn't ruin my whole project.
I first added the standard png's to see if he would show those, and he did. But when I add a png that I've created, he refuses to show it in the tableView. Does someone know why he refuses to show the image? (I created that png in photoshop by changing one of the standard png's and adding my image to it.)
var win = Titanium.UI.createWindow({
title:'tableViewRow',
backgroundColor:'#fff'
});
var regData = [
{leftImage:'KS_nav_ui.png', title:'gft', left:20, color:'black'},
{rightImage:'KS_nav_views.png', title:'grofvuil', left:20, color:'black'},
{leftImage:'glas.png', title:'glas', left:20, color:'black'}
];
var tbl = Titanium.UI.createTableView({
data:regData
});
win.add(tbl);
win.open();
Here's an image of the result I get in my android emulator (android api: Google APIs Android 2.2 and screen:HVGA)

If you are using AppC 1.8, you may just need a forward slash in your path '/'. (or backward if Windows)

I've solved it. What I did is I ran the application in an android amulator. I closed the app and went back to the homescreen (where you can save some apps). I pressed on menu and went to the settings. Than I went to applications. I opened 'manage applications' and remove the application. I closed the emulator and ran it again and the images were shown.
I don't know why you have to do it, but it worked for me. I hope I can save someone the frustration by posting the answer (I know I had them :D)