旋转后,recyclerview 行中的图像消失
Image in row of recyclerview disappears after rotation
在我的 recyclerview 中,我根据某些条件设置了一个图像(在 recyclerview 行中)可见或不可见。
但是在我旋转屏幕后图像消失了,如何使图像在回收站视图之后中保持可见在它的位置 ] 旋转屏幕?
感谢您的帮助,祝您节日快乐 ;)
我正在使用 SimpleAdapter 的实现。
public class SimpleAdapter extends RecyclerView.Adapter<SimpleAdapter.SimpleViewHolder> implements FollowRedirectsCallback {
public static class SimpleViewHolder extends RecyclerView.ViewHolder {
...
public final View icCancel;
public SimpleViewHolder(View view) {
super(view);
...
icCancel = view.findViewById(R.id.icCancel);
}
}
public SimpleAdapter(Context context, String[] data, long userId, int dlTypeValue) {
mContext = context;
userID = userId;
DLTypeValue = dlTypeValue;
if (data != null)
mData = new ArrayList<String>(Arrays.asList(data));
else mData = new ArrayList<String>();
}
public SimpleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
final View view = LayoutInflater.from(mContext).inflate(R.layout.simple_item, parent, false);
return new SimpleViewHolder(view);
}
@Override
public void onBindViewHolder(final SimpleViewHolder holder, final int position) {
...
// How to keep this image visible after rotation of the screen?
if (somecondition) {
holder.icCancel.setVisibility(View.VISIBLE);
}
}
编辑: 我在对应 activity:
中初始化我的适配器
public class DownloadsActivity extends BaseActivity {
RecyclerView recyclerView;
Parcelable state;
SimpleAdapter mAdapter;
SimpleSectionedRecyclerViewAdapter mSectionedAdapter;
SimpleSectionedRecyclerViewAdapter.Section[] dummy;
@AfterViews
public void init() {
recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
//setLayout Manager
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(linearLayoutManager);
recyclerView.setHasFixedSize(true);
dummy = new SimpleSectionedRecyclerViewAdapter.Section[sections.size()];
mSectionedAdapter = new
SimpleSectionedRecyclerViewAdapter(this, R.layout.section, R.id.section_text, mAdapter);
mSectionedAdapter.setSections(sections.toArray(dummy));
//Apply this adapter to the RecyclerView
recyclerView.setAdapter(mSectionedAdapter);
}
@Override
protected void onPause() {
super.onPause();
// save RecyclerView state
state = recyclerView.getLayoutManager().onSaveInstanceState();
}
@Override
protected void onResume() {
super.onResume();
if (inProgress) {
progresstxt.setVisibility(View.VISIBLE);
downloadprogress.setVisibility(View.VISIBLE);
}
// restore RecyclerView state
recyclerView.getLayoutManager().onRestoreInstanceState(state);
}
}
使用
int position = recyclerView.getLayoutManager().findFirstVisibleItemPosition();
让第一个位置可见。然后滚动到
位置
recyclerView.getLayoutManager().scrollToPosition( <position of interest> );
您可以将图像的可见性状态保存在 ArrayList
中,然后将其作为参数传递给适配器。在您的 Activity 中,使用 onSaveInstanceState
.
保存 ArrayList
public class YourActivity extends BaseActivity {
/* some codes */
// possible values are: VISIBLE, INVISIBLE, or GONE
private ArrayList<Integer> imagesState = new ArrayList<>();
/* some codes */
@Override
protected void onCreate(Bundle savedInstanceState) {
if(savedInstanceState != null) {
imagesState = savedInstanceState.getIntegerArrayList("key");
}
// Pass the imagesState to the adapter as a parameter here
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putIntegerArrayList("key", imagesState);
}
/* some codes */
}
然后在您的适配器中:
public class SimpleAdapter extends RecyclerView.Adapter<SimpleAdapter.SimpleViewHolder> implements FollowRedirectsCallback {
/* some codes */
public SimpleAdapter(Context context, String[] data, long userId, int dlTypeValue, ArrayList<Integer> imagesState) {
/* some codes */
this.imagesState = imagesState;
}
@Override
public void onBindViewHolder(SimpleViewHolder holder, int position) {
/* some codes */
if (imagesState.get(position) == View.VISIBLE)
holder.icCancel.setVisibility(View.VISIBLE);
else if(imagesState.get(position) == View.INVISIBLE)
holder.icCancel.setVisibility(View.INVISIBLE);
else
holder.icCancel.setVisibility(View.GONE);
}
}
在我的 recyclerview 中,我根据某些条件设置了一个图像(在 recyclerview 行中)可见或不可见。
但是在我旋转屏幕后图像消失了,如何使图像在回收站视图之后中保持可见在它的位置 ] 旋转屏幕?
感谢您的帮助,祝您节日快乐 ;)
我正在使用 SimpleAdapter 的实现。
public class SimpleAdapter extends RecyclerView.Adapter<SimpleAdapter.SimpleViewHolder> implements FollowRedirectsCallback {
public static class SimpleViewHolder extends RecyclerView.ViewHolder {
...
public final View icCancel;
public SimpleViewHolder(View view) {
super(view);
...
icCancel = view.findViewById(R.id.icCancel);
}
}
public SimpleAdapter(Context context, String[] data, long userId, int dlTypeValue) {
mContext = context;
userID = userId;
DLTypeValue = dlTypeValue;
if (data != null)
mData = new ArrayList<String>(Arrays.asList(data));
else mData = new ArrayList<String>();
}
public SimpleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
final View view = LayoutInflater.from(mContext).inflate(R.layout.simple_item, parent, false);
return new SimpleViewHolder(view);
}
@Override
public void onBindViewHolder(final SimpleViewHolder holder, final int position) {
...
// How to keep this image visible after rotation of the screen?
if (somecondition) {
holder.icCancel.setVisibility(View.VISIBLE);
}
}
编辑: 我在对应 activity:
中初始化我的适配器public class DownloadsActivity extends BaseActivity {
RecyclerView recyclerView;
Parcelable state;
SimpleAdapter mAdapter;
SimpleSectionedRecyclerViewAdapter mSectionedAdapter;
SimpleSectionedRecyclerViewAdapter.Section[] dummy;
@AfterViews
public void init() {
recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
//setLayout Manager
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(linearLayoutManager);
recyclerView.setHasFixedSize(true);
dummy = new SimpleSectionedRecyclerViewAdapter.Section[sections.size()];
mSectionedAdapter = new
SimpleSectionedRecyclerViewAdapter(this, R.layout.section, R.id.section_text, mAdapter);
mSectionedAdapter.setSections(sections.toArray(dummy));
//Apply this adapter to the RecyclerView
recyclerView.setAdapter(mSectionedAdapter);
}
@Override
protected void onPause() {
super.onPause();
// save RecyclerView state
state = recyclerView.getLayoutManager().onSaveInstanceState();
}
@Override
protected void onResume() {
super.onResume();
if (inProgress) {
progresstxt.setVisibility(View.VISIBLE);
downloadprogress.setVisibility(View.VISIBLE);
}
// restore RecyclerView state
recyclerView.getLayoutManager().onRestoreInstanceState(state);
}
}
使用
int position = recyclerView.getLayoutManager().findFirstVisibleItemPosition();
让第一个位置可见。然后滚动到
位置recyclerView.getLayoutManager().scrollToPosition( <position of interest> );
您可以将图像的可见性状态保存在 ArrayList
中,然后将其作为参数传递给适配器。在您的 Activity 中,使用 onSaveInstanceState
.
ArrayList
public class YourActivity extends BaseActivity {
/* some codes */
// possible values are: VISIBLE, INVISIBLE, or GONE
private ArrayList<Integer> imagesState = new ArrayList<>();
/* some codes */
@Override
protected void onCreate(Bundle savedInstanceState) {
if(savedInstanceState != null) {
imagesState = savedInstanceState.getIntegerArrayList("key");
}
// Pass the imagesState to the adapter as a parameter here
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putIntegerArrayList("key", imagesState);
}
/* some codes */
}
然后在您的适配器中:
public class SimpleAdapter extends RecyclerView.Adapter<SimpleAdapter.SimpleViewHolder> implements FollowRedirectsCallback {
/* some codes */
public SimpleAdapter(Context context, String[] data, long userId, int dlTypeValue, ArrayList<Integer> imagesState) {
/* some codes */
this.imagesState = imagesState;
}
@Override
public void onBindViewHolder(SimpleViewHolder holder, int position) {
/* some codes */
if (imagesState.get(position) == View.VISIBLE)
holder.icCancel.setVisibility(View.VISIBLE);
else if(imagesState.get(position) == View.INVISIBLE)
holder.icCancel.setVisibility(View.INVISIBLE);
else
holder.icCancel.setVisibility(View.GONE);
}
}