How to change shape color dynamically?

Question

You could modify it simply like this

GradientDrawable bgShape = (GradientDrawable)btn.getBackground();
bgShape.setColor(Color.BLACK);

For me, it crashed because getBackground returned a GradientDrawable instead of a ShapeDrawable.

So i modified it like this:

((GradientDrawable)someView.getBackground()).setColor(someColor);

This works for me, with an initial xml resource:

example.setBackgroundResource(R.drawable.myshape);
GradientDrawable gd = (GradientDrawable) example.getBackground().getCurrent();
gd.setColor(Color.parseColor("#000000"));
gd.setCornerRadii(new float[]{30, 30, 30, 30, 0, 0, 30, 30});
gd.setStroke(2, Color.parseColor("#00FFFF"), 5, 6);

Result of the above: http://i.stack.imgur.com/hKUR7.png

You can build your own shapes in Java. I did this for an iPhone like Page Controler and paint the shapes in Java:

/**
 * Builds the active and inactive shapes / drawables for the page control
 */
private void makeShapes() {

    activeDrawable = new ShapeDrawable();
    inactiveDrawable = new ShapeDrawable();
    activeDrawable.setBounds(0, 0, (int) mIndicatorSize,
            (int) mIndicatorSize);
    inactiveDrawable.setBounds(0, 0, (int) mIndicatorSize,
            (int) mIndicatorSize);

    int i[] = new int[2];
    i[0] = android.R.attr.textColorSecondary;
    i[1] = android.R.attr.textColorSecondaryInverse;
    TypedArray a = this.getTheme().obtainStyledAttributes(i);

    Shape s1 = new OvalShape();
    s1.resize(mIndicatorSize, mIndicatorSize);
    Shape s2 = new OvalShape();
    s2.resize(mIndicatorSize, mIndicatorSize);

    ((ShapeDrawable) activeDrawable).getPaint().setColor(
            a.getColor(0, Color.DKGRAY));
    ((ShapeDrawable) inactiveDrawable).getPaint().setColor(
            a.getColor(1, Color.LTGRAY));

    ((ShapeDrawable) activeDrawable).setShape(s1);
    ((ShapeDrawable) inactiveDrawable).setShape(s2);
}

hope this helps. Greez Fabian

Maybe someone else need to change color in the XML without create multiple drawables like I needed. Then make a circle drawable without color and then specify backgroundTint for the ImageView.

circle.xml

<?xml version="1.0" encoding="utf-8"?>
<shape
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">
</shape>

And in your layout:

<ImageView
    android:layout_width="50dp"
    android:layout_height="50dp"
    android:background="@drawable/circle"
    android:backgroundTint="@color/red"/>

Edit:

There is a bug regarding this method that prevents it from working on Android Lollipop 5.0 (API level 21). But have been fixed in newer versions.