Android 弹幕功能实现
直接上代码:
工具类
import android.animation.Animator;
import android.animation.ObjectAnimator;
import android.annotation.SuppressLint;
import android.content.Context;
import android.os.Handler;
import android.os.Message;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.view.animation.LinearInterpolator;
import android.widget.FrameLayout;
import java.util.List;
/**
* 弹幕视图，使用属性动画
*/
public class BarrageView extends FrameLayout {
private String Tag = BarrageView.class.getSimpleName();
private final int CODE_START = 1000;
private final int CODE_NEXT = 1001;
private final int CODE_END = 1002;
//数据源
private List datas;
private ViewHolder viewHolder;
//控件宽
private int barrageViewWidth;
//控件高
private int barrageViewHeight;
//弹幕行数
private int displayLines = 10;
//是否循环显示
private boolean isRepeat = true;
//动画时间
private long animationTime = 6 * 1000L;
//两条弹幕最小间隔时间
private long minIntervalTime = 1000L;
//两条弹幕最大间隔时间
private long maxIntervalTime = 3000L;
//大当前弹幕索引
private int currentIndex;
//弹幕状态
private boolean isStart;
//上一次出现的行数
private int lastLine = -1;
@SuppressLint("HandlerLeak")
private Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case CODE_START:
handler.sendEmptyMessage(CODE_NEXT);
break;
case CODE_NEXT:
if (isStart && datas != null && currentIndex < datas.size()) {
addView();
currentIndex++;
long interval = maxIntervalTime - minIntervalTime;
long randomSleepTime = minIntervalTime + (long)(interval > 0 ? Math.random() * interval : 0);
handler.sendEmptyMessageDelayed(CODE_NEXT, randomSleepTime);
} else {
handler.sendEmptyMessage(CODE_END);
}
break;
case CODE_END:
Log.d(Tag, "CODE_END");
if (isRepeat) {
if (currentIndex != 0) {
currentIndex = 0;
handler.sendEmptyMessage(CODE_NEXT);
}
}
break;
}
}
};
private LinearInterpolator linearInterpolator;
public BarrageView(Context context, AttributeSet attrs) {
super(context, attrs);
}
private void addView() {
final View itemView = viewHolder.getItemView(getContext(), datas.get(currentIndex), currentIndex);
addView(itemView);
itemView.setY(getItemRandomY());
itemView.measure(0, 0);
int itemViewWidth = itemView.getMeasuredWidth();
itemView.setX(this.barrageViewWidth);
if (linearInterpolator == null) {
linearInterpolator = new LinearInterpolator();
}
final ObjectAnimator anim = ObjectAnimator.ofFloat(itemView, "translationX", -itemViewWidth);
anim.setDuration(animationTime);
anim.setInterpolator(linearInterpolator);
//释放资源
anim.addListener(new Animator.AnimatorListener() {
@Override
public void onAnimationStart(Animator animation) {
}
@Override
public void onAnimationEnd(Animator animation) {
anim.cancel();
itemView.clearAnimation();
removeView(itemView);
}
@Override
public void onAnimationCancel(Animator animation) {
itemView.clearAnimation();
removeView(itemView);
}
@Override
public void onAnimationRepeat(Animator animation) {
}
});
anim.start();
}
/**
* 获得随机的Y轴的值
*/
private float getItemRandomY() {
//随机选择弹幕出现的行数位置，跟上一条位置不同行
int randomLine = lastLine;
if (displayLines > 1) {
while (randomLine == lastLine) {
randomLine = (int) (Math.random() * displayLines + 1);
}
}
lastLine =randomLine ;
//当前itemView y值
return (float) (barrageViewHeight*1.0 / displayLines * (randomLine - 1));
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
barrageViewWidth = getWidth();
barrageViewHeight = getHeight();
}
private int dip2px(Context context, float dpValue) {
float scale = context.getResources().getDisplayMetrics().density;
return (int) (dpValue * scale + 0.5f);
}
//设置数据
public void setData(List list, ViewHolder viewHolder) {
datas = list;
this.viewHolder = viewHolder;
}
public void start() {
isStart = true;
handler.sendEmptyMessage(CODE_START);
}
public void onResume() {
if (!isStart) {
isStart = true;
handler.sendEmptyMessage(CODE_NEXT);
}
}
public void onPause() {
isStart = false;
handler.removeMessages(CODE_NEXT);
}
public void cancle() {
isStart = false;
currentIndex = 0;
if (datas != null) {
datas.clear();
}
removeAllViews();
handler.removeMessages(CODE_NEXT);
}
public void onDestroy() {
cancle();
}
/**
* 获取显示行数
*
* @return 行数
*/
public int getDisplayLines() {
return displayLines;
}
/**
* 设置显示行数
*
* @param displayLines 行数
*/
public void setDisplayLines(int displayLines) {
if (displayLines <= 0) {
return;
}
this.displayLines = displayLines;
}
/**
* 是否重复
*
* @return 是否
*/
public boolean isRepeat() {
return isRepeat;
}
/**
* 设置是否重复
*
* @param repeat 是否
*/
public void setRepeat(boolean repeat) {
isRepeat = repeat;
}
/**
* 获取动画持续时间
*
* @return 时长ms
*/
public long getAnimationTime() {
return animationTime;
}
/**
* 设置动画持续时长
*
* @param animationTime ms
*/
public void setAnimationTime(long animationTime) {
this.animationTime = animationTime;
}
/**
* 获取最小间隔时间
*
* @return ms
*/
public long getMinIntervalTime() {
return minIntervalTime;
}
/**
* 设置最小间间隔时间
*
* @param minIntervalTime ms
*/
public void setMinIntervalTime(long minIntervalTime) {
if (minIntervalTime <= 0) {
return;
}
this.minIntervalTime = minIntervalTime;
}
/**
* 获取最大间隔时间
*
* @return ms
*/
public long getMaxIntervalTime() {
return maxIntervalTime;
}
/**
* 设置最大间间隔时间
*
* @param maxIntervalTime ms
*/
public void setMaxIntervalTime(long maxIntervalTime) {
if (maxIntervalTime <= 0) {
return;
}
this.maxIntervalTime = maxIntervalTime;
}
public interface ViewHolder {
View getItemView(Context context, Object item, int index);
}
}
bean类:
import java.io.Serializable;
/**
* 弹幕bean
*/
public class BarrageViewBean implements Serializable {
private String head;
private String name;
private String desc;
public BarrageViewBean(String head, String name, String desc) {
this.head = head;
this.name = name;
this.desc = desc;
}
public BarrageViewBean( String desc) {
this.desc = desc;
}
public String getHead() {
return head;
}
public void setHead(String head) {
this.head = head;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getDesc() {
return desc;
}
public void setDesc(String desc) {
this.desc = desc;
}
}
布局：
调用：
private fun showBarrageView(){
val data = CommonUtils.getAssetsData(AppContext.appContext, "barrview.json")
if (!TextUtils.isEmpty(data)) {
val list :List = Gson().fromJson(
data,
object : TypeToken>() {}.type
)
mBinding.barrageView.setData(list) { context, item, index ->
getItem(context, item as VipUserBean)
}
mBinding.barrageView.displayLines = 2 //设置行数
mBinding.barrageView.minIntervalTime = 800L //设置最小显示间隔时间
mBinding.barrageView.maxIntervalTime = 1200L //设置最大显示间隔时间
mBinding.barrageView.animationTime = 4000L //设置弹幕持续时长
mBinding.barrageView.start()
}
}