我正在编辑,使问题更简单,希望有助于得到一个准确的答案。

假设我有如下椭圆形状:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="oval">
    <solid android:angle="270"
           android:color="#FFFF0000"/>
    <stroke android:width="3dp"
            android:color="#FFAA0055"/>
</shape>

如何从一个活动类中以编程方式设置颜色?


当前回答

这样做:

    ImageView imgIcon = findViewById(R.id.imgIcon);
    GradientDrawable backgroundGradient = (GradientDrawable)imgIcon.getBackground();
    backgroundGradient.setColor(getResources().getColor(R.color.yellow));

其他回答

我没有工作,但当我设置色调颜色,它工作在形状绘制

 Drawable background = imageView.getBackground();
 background.setTint(getRandomColor())

需要android 5.0 API 21

这是对我有效的解决方案……也写在另一个问题里: 如何动态改变形状颜色?

//get the image button by id
ImageButton myImg = (ImageButton) findViewById(R.id.some_id);

//get drawable from image button
GradientDrawable drawable = (GradientDrawable) myImg.getDrawable();

//set color as integer
//can use Color.parseColor(color) if color is a string
drawable.setColor(color)

我的Kotlin扩展函数版本基于上述答案与Compat:

fun Drawable.overrideColor_Ext(context: Context, colorInt: Int) {
    val muted = this.mutate()
    when (muted) {
        is GradientDrawable -> muted.setColor(ContextCompat.getColor(context, colorInt))
        is ShapeDrawable -> muted.paint.setColor(ContextCompat.getColor(context, colorInt))
        is ColorDrawable -> muted.setColor(ContextCompat.getColor(context, colorInt))
        else -> Log.d("Tag", "Not a valid background type")
    }
}

这个问题之前已经回答过了,但是可以通过重写为kotlin扩展函数来实现现代化。

fun Drawable.overrideColor(@ColorInt colorInt: Int) {
    when (this) {
        is GradientDrawable -> setColor(colorInt)
        is ShapeDrawable -> paint.color = colorInt
        is ColorDrawable -> color = colorInt
    }
}

这样做:

    ImageView imgIcon = findViewById(R.id.imgIcon);
    GradientDrawable backgroundGradient = (GradientDrawable)imgIcon.getBackground();
    backgroundGradient.setColor(getResources().getColor(R.color.yellow));