Activity.java中的多个选定项目RecyclerView [英] Multiple selected items RecyclerView in Activity.java
问题描述
我有一个RecyclerView，其中的数据来自CardView中的本地JSON.单击一个或某些项目(更改所选项目的背景或突出显示)(例如在Line App中进行编辑)但没有Button或longpress时，我需要对所选项目实施.但是我不想使用StateListDrawable或(使用XML)，因为我有一些JSON数据需要稍后处理.
I have a RecyclerView with data from local JSON in CardView. I need to implement on selected items when one or some item clicked(change background the item selected or highlight) (like edit in Line App ) but without Button or longpress. But I don't want to use StateListDrawableor (using XML) because I have some JSON data which need to process later.
我需要Activity中的状态，例如布尔值或某种东西来保存我单击的每个项目，但是我再也没有任何解决方案.我已经阅读并尝试了一些教程，但是没有用.这是我现在的活动下面的内容:
I need a state in my Activity like a boolean value or something to save every item which I clicked but I don't have any solution again. I have read and try some tutorial but it's not working. This is below my Activity now :
adapter.setOnRecyclerViewClickedListener(new Adapter.OnRecyclerViewItemClickedListener() {
@Override
public void OnRecyclerViewItemClicked(int position) {
boolean selectedItem = false;
adapter.setOnRecyclerViewClickedListener(new Adapter.OnRecyclerViewItemClickedListener() {
@Override
public void OnRecyclerViewItemClicked(int position) {
/* ------ boolean variabel for adapter but still not work ----- */
JSONObject filteredtableList= null;
try {
filteredtableList= new JSONObject("response").getJSONObject("tTisch");
}
catch (JSONException e) {
e.printStackTrace();
}
if (recyclerView == null) {
try {
filteredtableList.has("true");
filteredtableList.put(status, true);
} catch (JSONException e) {
e.printStackTrace();
}
}
else {
try {
filteredtableList.put(status, true);
}
catch (JSONException e) {
e.printStackTrace();
}
}
adapter.updateData(filteredTableList);
//----------------------------------------------------
try {
Toast.makeText(TableActivity.this, filteredTableList.getJSONObject(position).getString("tischnr"), Toast.LENGTH_SHORT).show();
} catch (JSONException e) {
e.printStackTrace();
}
}
});
Adapter.java
Adapter.java
public int lastCheckedPosition = -1;
.........
.........
.........
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
if (position == lastCheckedPosition) {
holder.itemView.setBackgroundResource(R.color.colorRedTableOcc);
} else {
holder.itemView.setBackgroundResource(R.color.colorTableGreen);
}
try {
currItem = list.getJSONObject(position);
holder.txt_no_table.setText(currItem.getString("tischnr"));
} catch (JSONException e) {
e.printStackTrace();
}
}
@Override
public int getItemCount() {
return list.length();
}
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
public TextView txt_no_table;
public ViewHolder(View itemView) {
super(itemView);
itemView.setOnClickListener(this);
txt_no_table = (TextView) itemView.findViewById(R.id.txt_no_table_empty);
}
@Override
public void onClick(View itemView) {
recyclerViewItemClickedListener.OnRecyclerViewItemClicked(getAdapterPosition());
lastCheckedPosition = getAdapterPosition();
notifyItemRangeChanged(0,list.length());
}
}
JSON.json
JSON.json
..............
"t-tisch": [
{
"tischnr": 1,
"departement": 1,
"normalbeleg": 0,
"kellner-nr": 0,
"bezeich": "TABLE 01",
"roomcharge": false,
"betriebsnr": 0
},
{
"tischnr": 2,
"departement": 1,
"normalbeleg": 0,
"kellner-nr": 0,
"bezeich": "TABLE 02",
"roomcharge": false,
"betriebsnr": 0
},
............
这是我的活动
现在输出:
当我单击该项目时，它会突出显示(感谢@Burhanuddin Rashid)，但对我来说还是一半.我只能选择一个项目(我不能选择多个/更多项目).单击突出显示项时，我需要再次取消选择.
It's now highlight when I click the item (Thanks to @Burhanuddin Rashid) but its still half for my case. I only can select one item (I can't selected multiple/more items). I need to unselect again when I click the highlight item.
我尝试在JSON(上面的JSON代码)中写入新对象和键.按照我的逻辑，它将为每个项目是否被选中设置一个标志，但是仍然无法正常工作.
EDITED : I try to write new object and key in my JSON (JSON code above). In my logic, it will make a flag for every item is selected or not, but it still not work.
这是我的日志错误:
--------- beginning of crash
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.development_laptop.vhp_restotemp, PID: 3590
java.lang.NullPointerException: Attempt to invoke virtual method 'org.json.JSONObject org.json.JSONObject.put(java.lang.String, boolean)' on a null object reference
at com.example.development_laptop.vhp_restotemp.TableActivity$1.OnRecyclerViewItemClicked(TableActivity.java:74)
at com.example.development_laptop.vhp_restotemp.com.example.development_laptop.vhp_restotemp.recyclerview.source.Adapter$ViewHolder.onClick(Adapter.java:97)
at android.view.View.performClick(View.java:5198)
at android.view.View$PerformClick.run(View.java:21147)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
推荐答案
我完全更改了代码，但是它现在可以正常运行，这里的代码如下:
I totally change my code but its now work powerfully, here my code looks like :
-
我将
Adapter更改为通用适配器.它不处理任何数据，但是会扔给我的活动.
I change my
Adapterinto generic adapter. Its not process any data, but its throw to my activity.
public class Adapter extends RecyclerView.Adapter<Adapter.ViewHolder> {
public int lastCheckedPosition = -1;
private static OnRecyclerViewItemClickedListener recyclerViewItemClickedListener;
public void setOnRecyclerViewClickedListener (OnRecyclerViewItemClickedListener l) {
recyclerViewItemClickedListener = l;
}
public interface OnRecyclerViewItemClickedListener {
void OnRecyclerViewItemClicked(int position);
void OnRecyclerViewItemBind(ViewHolder holder, int position);
int OnRecyclerViewItemCount();
}
public Adapter() {
super();
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.table_item_empty, parent, false);
return new ViewHolder(v);
}
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
recyclerViewItemClickedListener.OnRecyclerViewItemBind(holder,position);
}
@Override
public int getItemCount() {
return recyclerViewItemClickedListener.OnRecyclerViewItemCount();
}
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
public TextView txt_no_table;
public ViewHolder(View itemView) {
super(itemView);
itemView.setOnClickListener(this);
txt_no_table = (TextView) itemView.findViewById(R.id.txt_no_table_empty);
}
@Override
public void onClick(View itemView) {
recyclerViewItemClickedListener.OnRecyclerViewItemClicked(getAdapterPosition());
}
}
}
我的Activity变成这样:
And My Activity become like this :
/*Add Click Listener*/
adapter.setOnRecyclerViewClickedListener(new Adapter.OnRecyclerViewItemClickedListener() {
@Override
public void OnRecyclerViewItemClicked(int position) {
try {
JSONObject currTable = filteredTableList.getJSONObject(position);
if (currTable.has("selected")) {
currTable.put("selected", !currTable.getBoolean("selected"));
} else {
currTable.put("selected",true);
}
adapter.notifyItemChanged(position);
} catch (JSONException e) {
e.printStackTrace();
}
try
{
Toast.makeText(TableActivity.this, filteredTableList.getJSONObject(position).getString("tischnr"), Toast.LENGTH_SHORT).show();
}
catch (JSONException e) {
e.printStackTrace();
}
}
@Override
public void OnRecyclerViewItemBind(Adapter.ViewHolder holder, int position) {
try {
JSONObject currTable = filteredTableList.getJSONObject(position);
holder.txt_no_table.setText(currTable.getString("tischnr"));
int queasy33Index = ProgramMethod.getJSONArrayIndex(queasy33List,"number2", currTable.getInt("tischnr"));
if (queasy33Index >= 0) {
holder.txt_no_table.setText(holder.txt_no_table.getText() + "-" + queasy33List.getJSONObject(queasy33Index).getString("key"));
}
if (currTable.has("selected") && currTable.getBoolean("selected")) {
holder.itemView.setBackgroundResource(R.color.colorRedTableOcc);
} else {
holder.itemView.setBackgroundResource(R.color.colorTableGreen);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
现在，点击侦听器将保存任何状态并保存到我的JSON文件中的布尔值中，如下所示:
Now the click listener save any state and save into boolean value in my JSON file like below :
感谢大家提供建议和出色的答案:)
Thanks to everyone with suggest and great answer :)
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