而我们要做的是一个下载列表,在下载的callback里面我们要去更新列表的progressBar还有Button的文本:
Activity中获取到下载的callback:
@Override
public void onProgress(long finished, long total, int progress) {
XLog.e(mInfoBean.getDownLoadUrl() + “-----------||||||” + progress);
String downloadPerSize = Kits.File.getDownloadPerSize(finished, total);
mInfoBean.setDownLoadStatus(STATUS_DOWNLOADING);
mInfoBean.setDownloadPerSize(downloadPerSize);
mInfoBean.setProgress(progress);
if (isCurrentListViewItemVisible(mPosition)) {
mTestDownLoadAdapter.setProgress(progress, mPosition, downloadPerSize);
}
}
适配器中暴露的用于更新progressBar进度的方法
/**
适配器的onBindViewHolder()中处理数据结果
@Override
public void onBindViewHolder(final TestDownLoadHolder holder, final int position) {
final AppInfoBean appInfoBean = data.get(position);
if (appInfoBean != null) {
ILFactory.getLoader().loadNet(holder.mIvDownPic, appInfoBean.getDownLoadPic(), ImgOptions.getDefImaOptions());
holder.mPbDownProgress.setProgress(appInfoBean.getProgress());
holder.mBtDownLoad.setText(appInfoBean.getDownloadPerSize());
holder.mBtDownLoad.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (getRecItemClick() != null) {
getRecItemClick().onItemClick(position, appInfoBean, 0, holder);
}
}
});
}
}
这里我们使用的是notifyItemChanged局部刷新而不是notifyDataSetChanged。讲道理我们到了这一步就已经可以满足需求了,然而…事实不讲道理:
[外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-D02S7a5j-1646116102674)(https://user-gold-cdn.xitu.io/2017/10/27/72395e18c6486bb49278862724e630b4?imageView2/0/w/1280/h/960/ignore-error/1)]
一闪一闪亮晶晶
额…原谅demo画得太丑了。这里我们可以发现…为毛我的图片…一闪一闪的,亮瞎我的狗眼了。
至于为什么会闪动?
猜测:
解疑:
ILFactory.getLoader().loadNet(holder.mIvDownPic, appInfoBean.getDownLoadPic(), ImgOptions.getDefImaOptions());
android:src="@mipmap/ic_launcher"
那我们的问题就聚焦在如何只更新一部分控件,其他控件不动
至于怎么解决呢…扒源码:
/**
position
has changed.notifyItemChanged(position, null);
.This is an item change event, not a structural change event. It indicates that any
position
is out of date and should be updated.position
retains the same identity./**
position
has changed with anThis is an item change event, not a structural change event. It indicates that any
position
is out of date and should be updated.position
retains the same identity.
在这里我们看到一句话:
@param payload Optional parameter, use null to identify a “full” update
传入“null”就是更新全部!那我们调用的时候是传入什么呢!看下:
public final void notifyItemChanged(int position) {
mObservable.notifyItemRangeChanged(position, 1);
}
继而调用:
public void notifyItemRangeChanged(int positionStart, int itemCount) {
notifyItemRangeChanged(positionStart, itemCount, null);
}
继而调用:
public void notifyItemRangeChanged(int positionStart, int itemCount, Object payload) {
// since onItemRangeChanged() is implemented by the app, it could do anything, including
// removing itself from {@link mObservers} - and that could cause problems if
// an iterator is used on the ArrayList {@link mObservers}.
// to avoid such problems, just march thru the list in the reverse order.
for (int i = mObservers.size() - 1; i >= 0; i–) {
mObservers.get(i).onItemRangeChanged(positionStart, itemCount, payload);
}
}
[捂脸] 一个大写的null…
OK,那我们修改下我们的调用方法:
/**
/**
这里我们传入了一个 “1”,这个1是随意传入的,其他值也可以。
继而我们需要重写onBindViewHolder方法如下:
@Override
public void onBindViewHolder(TestDownLoadHolder holder, int position, List payloads) {
XLog.e("--------------------------has payloads");
if (payloads.isEmpty()) {
XLog.e("--------------------------no payloads");
onBindViewHolder(holder, position);
} else {
XLog.e("--------------------------false payloads");
final AppInfoBean appInfoBean = data.get(position);
if (appInfoBean != null) {
holder.mPbDownProgress.setProgress(appInfoBean.getProgress());
holder.mBtDownLoad.setText(appInfoBean.getDownloadPerSize());
}
}
}
@Override
public void onBindViewHolder(final TestDownLoadHolder holder, final int position) {
final AppInfoBean appInfoBean = data.get(position);
if (appInfoBean != null) {
ILFactory.getLoader().loadNet(holder.mIvDownPic, appInfoBean.getDownLoadPic(), ImgOptions.getDefImaOptions());
holder.mPbDownProgress.setProgress(appInfoBean.getProgress());
holder.mBtDownLoad.setText(appInfoBean.getDownloadPerSize());
holder.mBtDownLoad.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (getRecItemClick() != null) {
getRecItemClick().onItemClick(position, appInfoBean, 0, holder);
}
}
});
}
}
getDownloadPerSize());
holder.mBtDownLoad.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (getRecItemClick() != null) {
getRecItemClick().onItemClick(position, appInfoBean, 0, holder);
}
}
});
}
}