android - Android椭圆形2色

Question

我有一个线性布局视图，其背景设置为椭圆形纯色。到目前为止，我的背景是圆圈。现在我想达到同样的效果，即使用可绘制的形状来获得具有 2 种颜色的圆圈。请参照附件。

Answer 1

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

    <gradient
        android:centerX="-1"
        android:type="sweep"
        android:startColor="color1"
        android:endColor="color2"
        />

</shape>

Answer 2

在您的可绘制文件夹 shape.xml 中创建 shape.xml：

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="oval" >
<gradient android:startColor="#0000FF" android:endColor="#00FF00"
android:angle="270"/>
</shape>

Answer 3

这可能来晚了，但我很难找到好的答案，所以听听我的看法。

我使用了一个自定义的可绘制对象来绘制圆，并使用了一个由位置数组配置为没有渐变过渡的 LinearGradient 着色器。渐变线方向在 LinearGradient 构造函数中配置（这里是对角线）。

public class MultiColorCircleDrawable extends Drawable {

    private Paint paint;
    private int[] colors;

    public MultiColorOvalDrawable(int[] colors) {
        this.colors = colors;
    }

    private void init() {
        paint = new Paint();
        paint.setShader(createShader());
    }

    private Shader createShader() {
        int[] colorsArray = new int[colors.length * 2];
        float[] positions = new float[colors.length * 2];

        for (int i = 0; i < colors.length; i++) {
            int y = i * 2;
            int color = colors[i];
            colorsArray[y] = color;
            colorsArray[y+1] = color;
            positions[y] = 1f / colors.length * i;
            positions[y+1] = 1f / colors.length * (i+1);
        }

        Rect bounds = getBounds();
        int width = bounds.right - bounds.left;
        int height = bounds.bottom - bounds.top;

        return new LinearGradient(0, 0, width, height, colorsArray, positions, Shader.TileMode.REPEAT);
    }

    @Override
    public void draw(Canvas canvas) {
        if (null == paint) {
            init();
        }

        Rect bounds = getBounds();
        int width = bounds.right - bounds.left;
        int height = bounds.bottom - bounds.top;
        canvas.drawCircle(width/2, height/2, (width/2) - strokeWidth, maskPaint);
    }

    @Override
    public void setAlpha(int i) {

    }

    @Override
    public void setColorFilter(ColorFilter colorFilter) {

    }

    @Override
    public int getOpacity() {
        return PixelFormat.OPAQUE;
    }
}