android 如何监听跑马灯效果

最新推荐文章于 2025-06-03 09:43:08 发布

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本文介绍了在Android中监听跑马灯效果的方法，特别是如何判断跑马灯完成一圈后停止的技巧。通过监听draw间隔，实现精确控制跑马灯的循环行为。

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如何监听跑马灯，跑完一圈？

思路很清楚，跑马灯会一直draw，但会发现文本跑完一圈后没停一下子，那监听draw的间隔不就行了？代码贴上：

使用：

tv.setOnMarqueeCompleteListener(new AutoText.OnMarqueeCompleteListener() {
		@Override
		public void onMarqueeComplete() {
		}
	});

自定义TextView：

import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.widget.TextView;

public class AutoText extends TextView {

	private OnMarqueeCompleteListener marqueeCompleteListener;

	private long mTime = 0;
	private long longs = 0;

	public AutoText(Context context) {
		this(context, null);
	}

	public AutoText(Context context, AttributeSet attrs) {
		this(context, attrs, 0);
	}

	public AutoText(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
	}

	// 开始监听
	public void setOnMarqueeCompleteListener(OnMarqueeCompleteListener marqueeCompleteListener) {
		this.marqueeCompleteListener = marqueeCompleteListener;
		// 避免一些机子反应慢，postDelayed一下
		postDelayed(new Runnable() {
			@Override
			public void run() {
				mTime = -1;
				longs = -1;
			}
		}, 3000);
	}

	@Override
	protected void onDraw(Canvas canvas) {
		super.onDraw(canvas);
		if (mTime == -1) {
			mTime = System.currentTimeMillis();
		} else if (longs == -1) {
			long time = System.currentTimeMillis();
			longs = time - mTime;
			mTime = time;
		} else if (longs != 0) {
			long time = System.currentTimeMillis();
			long thisLong = time - mTime;
			mTime = time;
			if (thisLong > 10 * longs) {
				if (null != marqueeCompleteListener) {
					LogUtil.i("AutoText", "MarqueeCompleteListener onMarqueeComplete");
					marqueeCompleteListener.onMarqueeComplete();
				}
			}
		}
	}

	public interface OnMarqueeCompleteListener {
		void onMarqueeComplete();
	}

}

实现跑马灯

xml里实现：

	android:ellipsize="marquee"
	android:focusable="true"
	android:focusableInTouchMode="true"
	android:gravity="center"
	android:lines="1"
	android:marqueeRepeatLimit="marquee_forever"

代码实现:

tvMarquee.setEllipsize(TextUtils.TruncateAt.MARQUEE);
tvMarquee.setSingleLine(true);
tvMarquee.setSelected(true);
tvMarquee.setFocusable(true);
tvMarquee.setFocusableInTouchMode(true);