Android自定义View--垂直ViewPager加跑马灯

背景
不多说，直接看此图。

image.png

关键技术
ViewPager有个setPageTransformer方法可以设置页面切换时的动画:

public void setPageTransformer(boolean reverseDrawingOrder, PageTransformer transformer)

/**
 * 自定义Pager切换模式
 */
class DefaultTransformer implements ViewPager.PageTransformer {

    @Override
    public void transformPage(View view, float position) {
        float alpha = 0;
        if (0 <= position && position <= 1) {
            alpha = 1 - position;
        } else if (-1 < position && position < 0) {
            alpha = position + 1;
        }
        view.setAlpha(alpha);
        view.setTranslationX(view.getWidth() * -position);
        float yPosition = position * view.getHeight();
        view.setTranslationY(yPosition);
    }
}

跑马灯TextView:

public class MarqueeText extends TextView {
    public MarqueeText(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    protected void onFocusChanged(boolean focused, int direction, Rect previouslyFocusedRect) {
        super.onFocusChanged(focused, direction, previouslyFocusedRect);
    }

    @Override
    public void onWindowFocusChanged(boolean hasWindowFocus) {
        if(hasWindowFocus) super.onWindowFocusChanged(hasWindowFocus);
    }

    @Override
    @ViewDebug.ExportedProperty(category = "focus")
    public boolean isFocused() {
        return true;
    }
}

代码地址在GitHub：地址