直播系统源码，图片一直滚动，循环滚动，竖向和横向

直播系统源码，图片一直滚动，循环滚动，竖向和横向实现的相关代码

竖向：

public class LoopScrollView extends View {<br>    private final int speed;<br>    private final Bitmap bitmap;<br> <br>    private Rect clipBounds = new Rect();<br>    private float offset = 0;<br> <br>    private boolean isStarted;<br> <br>    public LoopScrollView(Context context, AttributeSet attrs) {<br>        super(context, attrs);<br>        TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.ParallaxView, 0, 0);<br>        try {<br>            speed = ta.getDimensionPixelSize(R.styleable.ParallaxView_speed, 10);<br>            bitmap = BitmapFactory.decodeResource(getResources(), ta.getResourceId(R.styleable.ParallaxView_src, 0));<br>        } finally {<br>            ta.recycle();<br>        }<br>//        start();<br>    }<br> <br>    @Override<br>    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {<br>        super.onMeasure(widthMeasureSpec, heightMeasureSpec);<br>        setMeasuredDimension(bitmap.getWidth(), MeasureSpec.getSize(heightMeasureSpec));<br>    }<br> <br>    @Override<br>    public void onDraw(Canvas canvas) {<br>        super.onDraw(canvas);<br>        if (canvas == null) {<br>            return;<br>        }<br> <br>        canvas.getClipBounds(clipBounds);<br> <br>        float normalizedOffset = offset;<br>        float layerHeight = bitmap.getHeight();<br> <br>        if (offset <= -layerHeight) {<br>            offset += (floor(abs(normalizedOffset) / layerHeight) * layerHeight);<br>        }<br> <br>        float top = offset;<br>        while (top < clipBounds.height()) {<br>            canvas.drawBitmap(bitmap, 0, getBitmapTop(layerHeight, top), null);<br>            top += layerHeight;<br>        }<br> <br>        if (isStarted) {<br>            offset -= speed;<br>            postInvalidateOnAnimation();<br>        }<br>    }<br> <br>    private float getBitmapTop(float layerHeight, float top) {<br>        float bitmapTop = top;<br>        if (speed < 0) {<br>            bitmapTop = clipBounds.height() - layerHeight - top;<br>        }<br>        return bitmapTop;<br>    }<br> <br>    /**<br>     * Start the animation<br>     */<br>    public void start() {<br>        if (!isStarted) {<br>            isStarted = true;<br>            postInvalidateOnAnimation();<br>        }<br>    }<br> <br>    /**<br>     * Stop the animation<br>     */<br>    public void stop() {<br>        if (isStarted) {<br>            isStarted = false;<br>            invalidate();<br>        }<br>    }<br>}

横向：

public class LoopScrollView extends View {<br>    private final int speed;<br>    private final Bitmap bitmap;<br> <br>    private Rect clipBounds = new Rect();<br>    private int offset = 0;<br> <br>    private boolean isStarted;<br> <br>    public LoopScrollView(Context context, AttributeSet attrs) {<br>        super(context, attrs);<br>        TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.ParallaxView, 0, 0);<br>        try {<br>            speed = ta.getDimensionPixelSize(R.styleable.ParallaxView_speed, 10);<br>            bitmap = BitmapFactory.decodeResource(getResources(), ta.getResourceId(R.styleable.ParallaxView_src, 0));<br>        } finally {<br>            ta.recycle();<br>        }<br>        start();<br>    }<br> <br>    @Override<br>    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {<br>        super.onMeasure(widthMeasureSpec, heightMeasureSpec);<br>        setMeasuredDimension(MeasureSpec.getSize(widthMeasureSpec), bitmap.getHeight());<br>    }<br> <br>    @Override<br>    public void onDraw(Canvas canvas) {<br>        super.onDraw(canvas);<br>        if (canvas == null) {<br>            return;<br>        }<br> <br>        canvas.getClipBounds(clipBounds);<br> <br>        int normalizedOffset = offset;<br>        int layerWidth = bitmap.getWidth();<br>        if (offset < -layerWidth) {<br>            offset += (int) (floor(abs(normalizedOffset) / (float) layerWidth) * layerWidth);<br>        }<br> <br>        int left = offset;<br>        while (left < clipBounds.width()) {<br>            canvas.drawBitmap(bitmap, getBitmapLeft(layerWidth, left), 0, null);<br>            left += layerWidth;<br>        }<br> <br>        if (isStarted) {<br>            offset -= speed;<br>            postInvalidateOnAnimation();<br>        }<br>    }<br> <br>    private float getBitmapLeft(int layerWidth, int left) {<br>        float bitmapLeft = left;<br>        if (speed < 0) {<br>            bitmapLeft = clipBounds.width() - layerWidth - left;<br>        }<br>        return bitmapLeft;<br>    }<br> <br>    /**<br>     * Start the animation<br>     */<br>    public void start() {<br>        if (!isStarted) {<br>            isStarted = true;<br>            postInvalidateOnAnimation();<br>        }<br>    }<br> <br>    /**<br>     * Stop the animation<br>     */<br>    public void stop() {<br>        if (isStarted) {<br>            isStarted = false;<br>            invalidate();<br>        }<br>    }<br>}