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Xamarin - working with VectorDrawable in Imageview and Edittext

I face issue to apply vectordrawable at my imageView and Edittext
here is my tries to fix the issue
First I am using Xamarin.Android.Support.Vector.Drawable Version 23.4.0
Second I add AppCompatDelegate.CompatVectorFromResourcesEnabled = true; in onCreate of my Application
public class MyApplication : Application
{
public MyApplication(IntPtr handle, JniHandleOwnership ownerShip) : base(handle, ownerShip)
{
Log.Debug("App", "I am in oncreate application");
}
public override void OnCreate()
{
base.OnCreate();
AppCompatDelegate.CompatVectorFromResourcesEnabled = true;
}
}
*Third * usingAppCompatActivity to make sure my activity used AppCompatImageView instead of normal ImageView and try set drawable manually but it return with null (I dont know why this happen )
[Activity( Label = "Activity1", Theme = "#style/AppTheme")]
public class Activity1 : AppCompatActivity
{
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
SetContentView(Resource.Layout.test);
ImageView testImage = FindViewById<ImageView>(Resource.Id.imageViewTest);
Drawable drawable = VectorDrawableCompat.Create(Resources, Resource.Drawable.ic_arrow_back_white_24dp, null);
testImage.SetImageDrawable(drawable);
}
}
Fourth in my project .csproj I add build tools version 23.0.3
<AndroidSdkBuildToolsVersion>23.0.3</AndroidSdkBuildToolsVersion>
here is my full file content
?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="14.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
<PropertyGroup>
<AndroidSdkBuildToolsVersion>23.0.3</AndroidSdkBuildToolsVersion>
<AndroidDesignerPreferredDevice>Nexus 4</AndroidDesignerPreferredDevice>
<SelectedDevice>Nexus_5_API_21_x86</SelectedDevice>
<AndroidDesignerPreferredTheme>Theme.DeviceDefault</AndroidDesignerPreferredTheme>
</PropertyGroup>
</Project>
Fifth I reference my vector image app:srcCompat
but it still not working any one could help me fix this issue

I fix first half of my issue Simplly update to
Xamarin.Android.Support.Vector.Drawable Version 23.4.0.1
make sure you reference your vector images by this way app:srcCompat
related to EditText Image I think you cant set it from xml you need to use it via code here is the method
SetCompoundDrawablesWithIntrinsicBounds(Drawable left, Drawable top, Drawable right, Drawable bottom);
in my case I used leftdrawable so my method look like
SetCompoundDrawablesWithIntrinsicBounds(Resource.Drawable.MyDrawable, 0, 0, 0);
hope this help any one face same issue

Update: Forget the Old Solution. Just update to the latest Verison of Xamarin (Xamarin.Android 7.2.0.7) and the latest version of the support libs (25.3.1).
Old Solution:
Downgrade to Xamarin 4.2.0.680, use only the support libs version 23.3.0 (Latest stable 24.2.1 crashes on Android 4.4.4 but works on Android 6)
Also ensure this:
Put this static constructor in your Activity:
static Activity1()
{
AppCompatDelegate.CompatVectorFromResourcesEnabled = true;
}
Or add AppCompatDelegate.CompatVectorFromResourcesEnabled = true; to your Application class´ OnCreate method.
<AndroidSdkBuildToolsVersion> in your project shouldn't be nessessary anymore.
Use app:srcCompat, like you already do.
Have a look at the Dependencies of each support lib at Nuget
I have:
Xamarin.Android.Support.Animated.Vector.Drawable.dll 23.3.0
Xamarin.Android.Support.Design.dll 23.3.0
Xamarin.Android.Support.v14.Preference.dll 23.3.0
Xamarin.Android.Support.v4.dll 23.3.0
Xamarin.Android.Support.v7.AppCompat.dll 23.3.0
Xamarin.Android.Support.v7.Preference.dll 23.3.0
Xamarin.Android.Support.v7.RecyclerView.dll 23.3.0
Xamarin.Android.Support.Vector.Drawable.dll 23.3.0
Also make shure you reference Java.Interop.dll
Try out another vector drawable, for example from Material Design Icons (Click on an icon, chose Icon Package, .XML Vector Drawable).

Android: remove deprecation warning for Html.fromHtml

I would like to remove the deprecation warning for Html.fromHtml(string).
I tried to do like this:
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.N) {
htmlSpanned = Html.fromHtml(string,Html.FROM_HTML_MODE_LEGACY);
} else {
//noinspection deprecation
htmlSpanned = Html.fromHtml(string);
}
but it still gives me a warning during compilation:
Warning:(18, 31) [deprecation] fromHtml(String) in Html has been
deprecated

Well, the one-parameter fromHtml() is deprecated. The Build checks ensure that you will not call it on older devices, but it does not change the fact that it is deprecated with a compileSdkVersion of 24.
You have four choices:
Drop your compileSdkVersion below 24. This has rippling effects (e.g., you cannot use 24.x.x versions of the support libraries) and is not a great option.
Set your minSdkVersion to 24 and get rid of the one-parameter fromHtml() call. This is impractical in 2016.
Live with the strikethrough and Lint complaints.
Add the appropriate #SuppressLint annotation to the method, to get the IDE to stop complaining. As Ahlem Jarrar notes, the simplest way to add this is via the quick-fix.

If your minSdkVersion is 24 or higher, use the version of fromHtml() that takes some flags as a parameter . AFAIK, FROM_HTML_MODE_LEGACY would be the flag value to use for compatibility with the older flag-less fromHtml().
If your minSdkVersion is lower than 24, your choices are:
Always use the fromHtml() you are, possibly using the quick-fix (Alt-Enter) to suppress the Lint warning
Use both versions of fromHtml(): the one taking the flags if your app is running on an API Level 24+ device, or the one without the flags on older devices.

This was my solution at one point:
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
textField.setText(Html.fromHtml(htmlText, Html.FROM_HTML_MODE_COMPACT));
} else {
textField.setText(Html.fromHtml(htmlText);
}
It worked just fine.

You can try it. I mean your code looks well, I tried it and it worked for me.
// get our html content
String htmlAsString = getString(R.string.html);
Spanned htmlAsSpanned = Html.fromHtml(htmlAsString);
// used by TextView
// set the html content on the TextView
TextView textView = (TextView) findViewById(R.id.textView);
textView.setText(htmlAsSpanned);
Our you can try it:
#SuppressWarnings("deprecation")

Android or Kotlin or Google has created HtmlCompat which can be used instead of the method Html. Add this dependency implementation 'androidx.core:core:1.0.1' to the build.gradle file of your app. Make sure you use the latest version of androidx.core:core.
This allows you to use:
HtmlCompat.fromHtml(html, HtmlCompat.FROM_HTML_MODE_LEGACY);
You can convert the HTML.FROM_HTML_MODE_LEGACY into an additional parameter if you want. This gives you more control about it which flag to use.
You can read more about the different flags on the HTML Class documentation

setBackgroundDrawable() is API 16 and my app requires a minimum API 9 I get no error when building

I have my app that requires SDK 9+ with code containing setBackgroundDrawable() which is API level 16. I did not get any error while coding or building the apk. but I got about 50 reports of this error happening in google analytics and a few reports in my developers console.
When I run the lint checker It also doesn't warn me. I am using eclipse. Is there a reason why it doesn't fail to compile like usually when you add a method that's not supported by the minimum API or is it simply an eclipse bug?

First of all you get no error when building since you probably are building with SDK 16+ and the method is there. But if you install the apk to a 2.1 Android phone it will throw a MethodNotFound Exception. So in the future ALWAYS install your apk on a min-target device to see if you didn't forget something. Min-Target basically is only a filter for the PLAY store (and for lint warnings, etc.)
AFAIK moving from imageView.setBackground(...) to imageView.setBackgroundDrawable(...) was just an api style design choice. So if you look at the source of Android SDK 18 you will see:
/**
* Set the background to a given Drawable, or remove the background. If the
* background has padding, this View's padding is set to the background's
* padding. However, when a background is removed, this View's padding isn't
* touched. If setting the padding is desired, please use
* {#link #setPadding(int, int, int, int)}.
*
* #param background The Drawable to use as the background, or null to remove the
* background
*/
public void setBackground(Drawable background) {
//noinspection deprecation
setBackgroundDrawable(background);
}
So for now its absolutely irrelevant if you use one or the other - but of course this COULD change (but it's unlikely it does in the future since it would break nearly every app done before SDK 16) - basically it's fine to use setBackground() even on SDK 18+
So if you want to be on the future-proof but ugly side you could use a version fork depicted by the other answers
if(Build.VERSION.SDK_INT >= 16) {
//new code
} else {
//deprecated code
}
Just one thing, and maybe this is a personal style preference, I would not suppress Lint warnings with annotations like this:
#SuppressLint("NewApi")
#SuppressWarnings("deprecation")
I like to keep the warnings since maybe later if I want to refactor/move to higher SDK I could easily get rid of these ugly switches.
Update:
Google's v4 support library contains helper classes for sdk boiler plate code. In this instance you would use:
ViewCompat.setBackground(view,drawable);
which handles the SDK check for you.

Seems to be a bug in eclipse or your eclipse is not working perfectly. But you can try project clean and try. But code wise you can try something like this:
#SuppressLint("NewApi")
#SuppressWarnings("deprecation")
public void setImage(ImageView imageView, BitmapDrawable bd) {
if(Build.VERSION.SDK_INT > 16) {
imageView.setBackground(bd);
} else {
imageView.setBackgroundDrawable(bd);
}
}
You can call this function along with ImageView and bitmap drawable.

Having issue on Real Device using vector image in android. SVG-android

I use svg-android.jar from https://github.com/pents90/svg-android at its work fine but only on emulator devices in eclipse. Agrrrr. On real devices it just empty imageView on screen.
here is my code:
SVG svg = SVGParser.getSVGFromResource(getResources(), R.raw.test);
Drawable drawable = svg.createPictureDrawable();
imgView.setImageDrawable(drawable);
any suggestion?

On newer devices that have hardware rendering turned on by default, you need to explicitly turn on software rendering.
imgView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
I suspect this is probably your problem.

Use AppCompatImageView instead ImageView in xml like the below code
<android.support.v7.widget.AppCompatImageView
android:tint="#d74313"
app:srcCompat="#drawable/circle_icon"
android:layout_width="30sp"
android:layout_height="30sp" />
and in your build.gradle
android {
defaultConfig {
vectorDrawables {
useSupportLibrary = true
}
}
}
If the above doesn't work, try this also in your application class
public class App extends Application {
#Override public void onCreate() {
super.onCreate();
// Make sure we use vector drawables
AppCompatDelegate.setCompatVectorFromResourcesEnabled(true);
}
}

build for different targets conditionally

I have been building for API 14 so far. I'm trying to get ready now, so I downloaded and specified API 7 as my target. I have some compilation errors because a few api's I was using in API14 aren't available in API7.
I am wondering how I could put them in conditionals. Something on the lines of:
if (API_14)
{
if (mTextEdit.isEmpty()) {
// Do Something
}
} else if (API_7){
if (mTextEdit.matches("")) {
// Do the same thing
}
}
This has to be a compile time conditional switch because otherwise my code won't even compile.
I've heard before that pre-processors are not supported in Java, so I welcome suggestions on how best to manage my source which I'm targeting for multiple versions.
Edit:
I also am running into trouble with my state list drawable:
<selector xmlns:android="http://schemas.android.com/apk/res/android" >
<item
android:state_pressed="true"
android:drawable="#android:color/holo_orange_dark" />
<item android:drawable="#android:color/transparent" />
</selector>
Of course, hold_orange_dark isn't available in API7. I'd like to be able to manage those as well.

You can't do ifs, or you'll have a crash on older devices.
You have to use Java Reflection to use methods from more recent APIs conditionally.
An example: http://mobile.tutsplus.com/tutorials/android/java-reflection/

For your resources you can specify different directories for different platform versions. So you'd make a Values-v14 directory to have a copy of any resources that use anything from that API version and a Values directory so Values would be used by default and Values-v14 would only be used if the device was version 14.
As for doing it programmatically, you could try a Try-Catch like so-
try {
//Insert ICS stuff here
} catch(NoSuchMethodError e){
}
Or you could try this-
public static boolean isHoneycomb() {
return Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB;
}