I have a problem when I am trying to setBackground() of a CardView programatically in KitKat.When the application is running on Android L there is no problem in my code :
Drawable drawable = new BitmapDrawable(appContext.getResources(), bitmap);
if (cardView != null) {
cardView.setBackground(drawable);
}
But when it runs in API older than Android L I get this error: android.graphics.drawable.BitmapDrawable cannot be cast to android.support.v7.widget.RoundRectDrawableWithShadow.
I found out that this is known issue and there is work around where you want to set a colour as a background of the card, but is there any solution with which I could set the bitmap for background programatically? Do you have any idea how could I create RoundRectDrawableWithShadow from my BitmapDrawable?
Do you have any idea how could I create RoundRectDrawableWithShadow from my BitmapDrawable?
Don't do it unless you wish to rewrite your own CardView implementation.
RoundRectDrawableWithShadow is a package private class used to take the color you supplied by app:cardBackgroundColor or setCardBackgroundColro(int) and wrap it in a rounded rectangle with shadow to produce a drawable.
Since elevation was introduced in API 21 the shadow is painted as part of CardView background drawable on prior platforms so you can't set your own background via setBackground(*).
is there any solution with which I could set the bitmap for background programatically?
You could put a View, *Layout, etc. in the card and set a rounded drawable background on it. It will not be effective performance-wise though.
https://developer.android.com/reference/android/support/v4/graphics/drawable/RoundedBitmapDrawable.html
So yeah, if you absolutely need something else than solid color, go with a View.setBackground
Related
I have an ImageView with the source being an ImageAsset.
My image is a circle with a plus and I am looking to colour the inside of the circle only. How do I do that?
Using setBackgroundColor colours the whole of the view thus giving a square background like this:
.
You can apply a color tint to your ImageView. This will not affect your background if it's transparent, just the colored part (which is the circle and the plus)
imageView.setColorFilter(ContextCompat.getColor(context, R.color.COLOR_YOUR_COLOR),
android.graphics.PorterDuff.Mode.MULTIPLY);
Update
Using android.graphics.PorterDuff.Mode.SRC_IN will also work (if you don't need to multiply the source and destination pixels)
Update 2
Since the destination part is not colored than the best solution is to use VectorDrawable.
You can use VectorChildFinder to find inner parts of your SVG resource and change its color.
VectorChildFinder vector = new VectorChildFinder(this, R.drawable.my_vector, imageView);
VectorDrawableCompat.VFullPath path1 = vector.findPathByName("path1");
path1.setFillColor(Color.RED);
imageView.invalidate();
to create your SVG, follow these steps :
Just click right button on folder(drawable for ex.) and choose:
then choose:
I have been working on android on some time, but there is a common problem which i face many times. The problem is there are multiple view where in i assign the view a background drawable for background, such as:
As can be seen in the above example the background drawable for both the views is same but only difference in the both background drawables xml file is the solid and stroke colour. Is there any other better way to do this where i just create a generic background drawable and change the colour of the components from xml and id not possible in xml instead of creating a new drawable each time for each solid colour and stroke colour variation.
No this is not possible in XML. However, it is possible using Java.
ShapeDrawable shapeDrawable = (ShapeDrawable) ContextCompat.getDrawable(getActivity(), R.drawable.name);
shapeDrawable.getPaint().setColor(ContextCompat.getColor(mContext,R.color.colorToSet))
Android SDK provides the following icons.
Is there a way to set a color to those .. and if possible, how to do so?
<ImageView
android:id="#+id/share_button"
style="#style/IconNav"
android:src="#android:drawable/ic_menu_share"/>
<ImageView
android:id="#+id/bookmark_button"
style="#style/IconNav"
android:src="#android:drawable/ic_input_get"/>
UPDATE
After doing a complete refresh of the project, it turns out the tint attribute in Xml did the trick.
For the short answer
.. this is the solution that worked for me - adding the property to the ImageView xml:
android:tint="#color/grass_dark"
The answer from #goldenb is a thorough run through of the different ways to solve for this, so am marking that one as the answer.
You can indeed use a tint as a way of changing an ImageView's colour, BUT you should be reminded that the android:tint will always be applied on top of the original colour.
as stated by blogger danlew
ImageView's tint mixes the tint color with the original asset. What you want is for the tint color to take over entirely; instead it
applies the tint on top of the existing color. So, for example, if the
source asset is black, and you want it to be #77FFFFFF (a translucent
shade of white), you'll actually end up getting that shade of white
with a black background beneath it.
android:tint is limited to ImageView. You want to be able to tint any Drawable in any View.
One possible alternative would be for you to use android ColorFilter
According to the official documentation:
A color filter can be used with a Paint to modify the color of each pixel drawn with that paint. This is an abstract class that should never be used directly.
There are lots of more or less complex things you can do with ColorFilter but how can you apply this then?
One simple example from another so question is:
//White tint
imageView.setColorFilter(Color.argb(255, 255, 255, 255));
or
imageView.setColorFilter(ContextCompat.getColor(context,R.color.COLOR_YOUR_COLOR))
Or a more complete answer here in SO from here
ImageView redCircle = (ImageView) findViewById(R.id.circle_red_imageview);
ImageView greenCircle = (ImageView) findViewById(R.id.circle_green_imageview);
ImageView blueCircle = (ImageView) findViewById(R.id.circle_blue_imageview);
// we can create the color values in different ways:
redCircle.getDrawable().setColorFilter(Color.RED, PorterDuff.Mode.MULTIPLY );
greenCircle.getDrawable().setColorFilter(0xff00ff00, PorterDuff.Mode.MULTIPLY );
blueCircle.getDrawable().setColorFilter(getResources().getColor(R.color.blue), PorterDuff.Mode.MULTIPLY );
You should check these links if you want to learn more
SO - What is the difference between background, backgroundTint, backgroundTintMode attributes in android layout xml?
setColorFilter()
Fast Android asset theming with ColorFilter
SO-Modifying the color of an android drawable
You can use a bitmap with a tint. Add this to your drawables folder.
ic_input_get_colored.xml :
<?xml version="1.0" encoding="utf-8"?>
<bitmap xmlns:android="http://schemas.android.com/apk/res/android"
android:src="#android:drawable/ic_input_get"
android:tint="#color/yourDesiredColor"/>
I have an image in a resource file.
Drawable draw = getResources().getDrawable(R.drawable.my_icon);
The image has a transparent background.
Is there a way to programmatically set the background color to the Drawable before using the end product further in my code?
I think Drawing with PorterduffXferMode may help you in your case. This way you can merge two images (your image and a overlay completly in your color you want to replace the transparent pixels with) in many different ways.
Different porterduff modes explaned:
http://www.ibm.com/developerworks/java/library/j-mer0918/
Android example:
http://www.vogella.com/code/ApiDemos/src/com/example/android/apis/graphics/Xfermodes.html
This way you draw the result inside a new Bitmap. (SRC_OVER should work in your case if your image is the src and the background is used as the dst)
setColorFilter() with Porterduff SRC will break the transparent of drawable.
I used this in my code, and it work
disabledIcon = ContextCompat.getDrawable(getContext(), resId);
disabledIcon = DrawableCompat.wrap(disabledIcon);
disabledIcon.mutate(); // to not share its state with any other drawable
DrawableCompat.setTint(disabledIcon, ContextCompat.getColor(getContext(), R.color.button_text_disabled));
It seems background images are automatically shrunk in Android, for example, I use setBackgroundDrawable to set background of a view:
Drawable background = getBackground();
myView.setBackgroundDrawable(background);
Instead of shrinking, I want the image to be cropped to fit the screen size. How to do it? Thanks.
Finally I fixed this problem. I use BitmapDrawable instead of Drawable, since BitmapDrawable has method setGravity(int) which can set the gravity to position/stretch the object.