首先，效果图。分类似至360检测到的骚扰电话页面：

布局非常easy，上面是一个RelativeLayout，以下一个Button.

功能：

（1）弹幕生成后自己主动从右側往左側滚动（TranslateAnimation）。弹幕消失后立马被移除。

（2）弹幕位置随机出现。而且不反复（防止文字重叠）。

（3）字体大小在一定范围内随机改变。字体颜色也能够设置。

（4）自己定义先减速，后加速的Interpolator，弹幕加速进入、减速停留、然后加速出去。

1.Activity代码：

/*** 简易弹幕效果实现* Created by admin on 15-6-4.*/
public class MainActivity extends ActionBarActivity {private MyHandler handler;//弹幕内容private TanmuBean tanmuBean;//放置弹幕内容的父组件private RelativeLayout containerVG;//父组件的高度private int validHeightSpace;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);containerVG = (RelativeLayout) findViewById(R.id.tanmu_container);tanmuBean = new TanmuBean();tanmuBean.setItems(new String[]{"測试一下", "弹幕这东西真不好做啊", "总是出现各种问题~~", "也不知道都是为什么？麻烦！", "哪位大神能够帮帮我啊？", "I need your help.","測试一下", "弹幕这东西真不好做啊", "总是出现各种问题~~", "也不知道都是为什么？麻烦！

", "哪位大神能够帮帮我啊？", "I need your help.", "測试一下", "弹幕这东西真不好做啊", "总是出现各种问题~~", "也不知道都是为什么？麻烦！

", "哪位大神能够帮帮我啊？", "I need your help."}); handler = new MyHandler(this); //開始弹幕 View startTanmuView = findViewById(R.id.startTanmu); startTanmuView.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { if (containerVG.getChildCount() > 0) { return; } existMarginValues.clear(); new Thread(new CreateTanmuThread()).start(); } }); } //每2s自己主动加入一条弹幕 private class CreateTanmuThread implements Runnable { @Override public void run() { int N = tanmuBean.getItems().length; for (int i = 0; i < N; i++) { handler.obtainMessage(1, i, 0).sendToTarget(); SystemClock.sleep(2000); } } } //须要在主线城中加入组件 private static class MyHandler extends Handler { private WeakReference<MainActivity> ref; MyHandler(MainActivity ac) { ref = new WeakReference<>(ac); } @Override public void handleMessage(Message msg) { super.handleMessage(msg); if (msg.what == 1) { MainActivity ac = ref.get(); if (ac != null && ac.tanmuBean != null) { int index = msg.arg1; String content = ac.tanmuBean.getItems()[index]; float textSize = (float) (ac.tanmuBean.getMinTextSize() * (1 + Math.random() * ac.tanmuBean.getRange())); int textColor = ac.tanmuBean.getColor(); ac.showTanmu(content, textSize, textColor); } } } } private void showTanmu(String content, float textSize, int textColor) { final TextView textView = new TextView(this); textView.setTextSize(textSize); textView.setText(content); // textView.setSingleLine(); textView.setTextColor(textColor); int leftMargin = containerVG.getRight() - containerVG.getLeft() - containerVG.getPaddingLeft(); //计算本条弹幕的topMargin(随机值，可是与屏幕中已有的不反复) int verticalMargin = getRandomTopMargin(); textView.setTag(verticalMargin); LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT); params.addRule(RelativeLayout.ALIGN_PARENT_TOP); params.topMargin = verticalMargin; textView.setLayoutParams(params); Animation anim = AnimationHelper.createTranslateAnim(this, leftMargin, -ScreenUtils.getScreenW(this)); anim.setAnimationListener(new Animation.AnimationListener() { @Override public void onAnimationStart(Animation animation) { } @Override public void onAnimationEnd(Animation animation) { //移除该组件 containerVG.removeView(textView); //移除占位 int verticalMargin = (int) textView.getTag(); existMarginValues.remove(verticalMargin); } @Override public void onAnimationRepeat(Animation animation) { } }); textView.startAnimation(anim); containerVG.addView(textView); } //记录当前仍在显示状态的弹幕的位置（避免反复） private Set<Integer> existMarginValues = new HashSet<>(); private int linesCount; private int getRandomTopMargin() { //计算用于弹幕显示的空间高度 if (validHeightSpace == 0) { validHeightSpace = containerVG.getBottom() - containerVG.getTop() - containerVG.getPaddingTop() - containerVG.getPaddingBottom(); } //计算可用的行数 if (linesCount == 0) { linesCount = validHeightSpace / ScreenUtils.dp2px(this, tanmuBean.getMinTextSize() * (1 + tanmuBean.getRange())); if (linesCount == 0) { throw new RuntimeException("Not enough space to show text."); } } //检查重叠 while (true) { int randomIndex = (int) (Math.random() * linesCount); int marginValue = randomIndex * (validHeightSpace / linesCount); if (!existMarginValues.contains(marginValue)) { existMarginValues.add(marginValue); return marginValue; } } } }

2.平移动画生成工具：

public class AnimationHelper {/*** 创建平移动画*/public static Animation createTranslateAnim(Context context, int fromX, int toX) {TranslateAnimation tlAnim = new TranslateAnimation(fromX, toX, 0, 0);//自己主动计算时间long duration = (long) (Math.abs(toX - fromX) * 1.0f / ScreenUtils.getScreenW(context) * 4000);tlAnim.setDuration(duration);tlAnim.setInterpolator(new DecelerateAccelerateInterpolator());tlAnim.setFillAfter(true);return tlAnim;}
}

ScreenUtils是用来获取屏幕宽高、dp与px之间互转的工具类。

3.自己定义的Interpolator。事实上仅仅有一行代码

public class DecelerateAccelerateInterpolator implements Interpolator {//input从0～1，返回值也从0～1.返回值的曲线表征速度加减趋势@Overridepublic float getInterpolation(float input) {return (float) (Math.tan((input * 2 - 1) / 4 * Math.PI)) / 2.0f + 0.5f;}
}

4.TanmuBean是一个实体类

public class TanmuBean {private String[] items;private int color;private int minTextSize;private float range;public TanmuBean() {//init default valuecolor = Color.parseColor("#eeeeee");minTextSize = 16;range = 0.5f;}public String[] getItems() {return items;}public void setItems(String[] items) {this.items = items;}public int getColor() {return color;}public void setColor(int color) {this.color = color;}/*** min textSize, in dp.*/public int getMinTextSize() {return minTextSize;}public void setMinTextSize(int minTextSize) {this.minTextSize = minTextSize;}public float getRange() {return range;}public void setRange(float range) {this.range = range;}
}

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源代码下载：http://download.csdn.net/detail/books1958/9005279