Android的 - 动态更新的一个ArrayList项目后自定义的ListView添加 [英] Android - Dynamically Updating a custom ListView after items in an ArrayList are added
问题描述
我有一个显示来自一个ArrayList迈出了最初填充自定义的ListView一个活动，然后用户可以添加到这个列表，我有没有问题的存储。我有显示添加的项目问题。到目前为止，C $ CS的$我在网上看到使用ArrayAdapter和他们只是用简单的ListView控件，而不是一个自定义的。
I have an activity that displays an initially populated custom ListView taken from an ArrayList, the user can then add to this list which I have no problem storing. I'm having problems displaying the added items. So far, the codes I see online use ArrayAdapter and they're only using the simple listView and not a custom one.
下面是相关文件：
list_row_layout.xml
list_row_layout.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="@+id/variant"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:text="variant" />
<TextView
android:id="@+id/quantity"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:text="quantity" />
<TextView
android:id="@+id/unit"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_marginRight="221dp"
android:layout_toLeftOf="@+id/quantity"
android:text="unit" />
</RelativeLayout>
下面是具有ListView控件元素的一部分，在我activity_order_form.xml。
Here is the part in my activity_order_form.xml that has the listView element.
<RelativeLayout
android:id="@+id/relativeLayout3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_below="@+id/relativeLayout2"
android:orientation="vertical" >
<TextView
android:id="@+id/textViewVariantB"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="94dp"
android:text="Variant"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="@+id/textViewUnit"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:layout_marginRight="123dp"
android:text="Unit"
android:textAppearance="?android:attr/textAppearanceLarge" />
<ListView
android:id="@+id/listViewProductOrder"
android:layout_width="match_parent"
android:layout_height="350dp"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_below="@+id/textViewVariantB" >
</ListView>
</RelativeLayout>
下面是其中的ArrayList存储类。
Here is the class where the ArrayList are stored.
public class CurrentOrderClass {
private String productName;
//ArrayLists
private ArrayList<String> variantArray = new ArrayList<String>();
private ArrayList<String> unitArray = new ArrayList<String>();
private ArrayList<Integer> quantityArray = new ArrayList<Integer>();
//TODO ArrayList functions
public ArrayList<String> getUnitArray() {
return unitArray;
}
public void setUnitArray(ArrayList<String> unitArray) {
this.unitArray = unitArray;
}
public void addToUnitArray(String unit){
this.unitArray.add(unit);
}
public ArrayList<Integer> getQuantityArray() {
return quantityArray;
}
public void setQuantityArray(ArrayList<Integer> quantityArray) {
this.quantityArray = quantityArray;
}
public void addToQuantityArray(int quantity){
this.quantityArray.add(quantity);
}
public ArrayList<String> getVariantArray() {
return variantArray;
}
public void setVariantArray(ArrayList<String> variantArray) {
this.variantArray = variantArray;
}
public void addToVariantArray(String variantArray){
this.variantArray.add(variantArray);
}
}
下面是CustomListAdapter.java文件
Here is the CustomListAdapter.java file
public class CustomListAdapter extends BaseAdapter {
private ArrayList<CurrentOrderClass> listData;
private LayoutInflater layoutInflater;
public CustomListAdapter(Context context, ArrayList<CurrentOrderClass> listData) {
this.listData = listData;
layoutInflater = LayoutInflater.from(context);
}
@Override
public int getCount() {
return listData.size();
}
@Override
public Object getItem(int position) {
return listData.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = layoutInflater.inflate(R.layout.list_row_layout, null);
holder = new ViewHolder();
holder.variantView = (TextView) convertView.findViewById(R.id.variant);
holder.unitView = (TextView) convertView.findViewById(R.id.unit);
holder.quantityView = (TextView) convertView.findViewById(R.id.quantity);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.variantView.setText(listData.get(position).getVariantArray().get(position).toString());
holder.unitView.setText(listData.get(position).getUnitArray().get(position).toString());
holder.quantityView.setText(String.valueOf(listData.get(position).getQuantityRow()));
return convertView;
}
static class ViewHolder {
TextView variantView;
TextView unitView;
TextView quantityView;
}
}
这是我的OrderForm.java活动的一部分，这显示的onCreate和填充ListView控件，以及在那里用户输入而采取的一部分。该方法
This is part of my OrderForm.java activity, this shows the onCreate and the method that populates the listView, as well as the part where user input is taken.
public class OrderForm extends Activity {
public TextView tv;
private int variantPosition;
CustomListAdapter customListAdapter;
CurrentOrderClass currentOrder = new CurrentOrderClass();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_order_form);
tv = (TextView)findViewById(R.id.textViewProduct);
//set variants here
popolateItem();
//set current order listview here
ArrayList image_details = getListData();
final ListView lv1 = (ListView) findViewById(R.id.listViewProductOrder);
customListAdapter = new CustomListAdapter(this, image_details);
lv1.setAdapter(customListAdapter);
}
private ArrayList getListData() {
ArrayList results = new ArrayList();
for(int i = 0; i < 10; i++){
currentOrder.getQuantityArray().add(i);
currentOrder.getUnitArray().add("Sample text here." + i);
currentOrder.getVariantArray().add("Another sample text here" + i);
results.add(currentOrder);
}
return results;
}
//....snip snip excess code.....
//This is the part wherein I add new items to the ArrayList in the class
//After this, I'm not sure how to proceed
currentOrder.setProductName(product.getName());
currentOrder.addToQuantityArray(newQuantity);
currentOrder.addToUnitArray(product.getUnit()[position]);
currentOrder.addToVariantArray(product.getVariant()[variantPosition]);
Log.d("Angelo", currentOrder.getProductName() + " "
+ currentOrder.getQuantityArray() + " "
+ currentOrder.getUnitArray() + " "
+ currentOrder.getVariantArray());
}
我也试过把 customListAdapter.notifyDataSetChanged（）;
I also tried to place customListAdapter.notifyDataSetChanged(); after the Log entry but nothing happened. Any ideas anyone? Thanks.
的求解和修改之后编辑。
只要按照下面FD的回答，并添加他那里指定的功能，之后的2函数调用。现在，你要修改 getListData（）的功能是这样的：
Just follow FD's answer below and add the function he specified there and the 2 function calls after that. Now, you want to modify your getListData() function like this:
private ArrayList getListData() {
ArrayList results = new ArrayList();
int loopUntil;
/* Two scenarios
* First ---> the user started the activity for the first time, which means that the pre-populated list is what we want
* if this is the case, look at the else part of the boolean statement, it only loops until 10
* and in addition, populates those elements
* Second ---> the user has set something already and we want to populate until that element.
*
*/
if(currentOrder.getQuantityArray().size() > 10){
loopUntil = currentOrder.getQuantityArray().size();
for(int i = 0; i < loopUntil; i++){
currentOrder.getQuantityArray();
currentOrder.getUnitArray();
currentOrder.getVariantArray();
results.add(currentOrder);
}
}
else{
loopUntil = 10;
for(int i = 0; i < loopUntil; i++){
currentOrder.getQuantityArray().add(i);
currentOrder.getUnitArray().add("Sample text here." + i);
currentOrder.getVariantArray().add("Another sample text here" + i);
results.add(currentOrder);
}
}
return results;
}
第一个条件的时候没有超出项目执行pre-人口之一，因为else语句循环只有等到pre-居住项目（项目编号9，指数0）。这个循环将确保所有你添加到ArrayList被添加到ListView。
The first condition executes when there is an item beyond the pre-populated one, since the else statement loops only until the pre-populated item (item number 9, index 0). This loop ensures that everything you add to the ArrayList gets added to the ListView.
当活动被打开首次和那里应该是没有任何该列表中还只是需要填充自己的那些第二个条件执行
The second condition executes when the activity is opened for the first time and there's supposed to be nothing in that list yet except the ones that you populated yourself.
推荐答案
您适配器没有得到新的数据，因为你有自己的一套数据初始化。
Your adapter does not get the new data, because you are initializing it with its own set of data.
一个可能性就是实例化一个新的适配器，并将其分配到ListView。
One possibility would be to instantiate a new adapter and assign it to the ListView.
添加一个字段为您的ListView在您的活动：
Add a field for your ListView in your activity:
public TextView tv;
private int variantPosition;
CustomListAdapter customListAdapter;
CurrentOrderClass currentOrder = new CurrentOrderClass();
ListView myListView; //Listview here
在的onCreate，设置myListView指向您的ListView：
In onCreate, set myListView to point to your ListView:
final ListView lv1 = (ListView) findViewById(R.id.listViewProductOrder)
myListView = lv1;
最后，当你改变你的数据，创建新数据的新适配器：
Finally, when you change your data, create a new Adapter for the new data:
myListView.setAdapter(new CustomListAdapter(this, getListData());
另外，修改自定义适配器包含setListData方法：
Alternatively, modify your Custom adapter to contain a setListData method:
public class CustomListAdapter extends BaseAdapter {
private ArrayList<CurrentOrderClass> listData;
private LayoutInflater layoutInflater;
public CustomListAdapter(Context context, ArrayList<CurrentOrderClass> listData) {
this.listData = listData;
layoutInflater = LayoutInflater.from(context);
}
public void setListData(ArrayList<CurrentOrderClass> data){
listData = data;
}
@Override
public int getCount() {
return listData.size();
}
@Override
public Object getItem(int position) {
return listData.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = layoutInflater.inflate(R.layout.list_row_layout, null);
holder = new ViewHolder();
holder.variantView = (TextView) convertView.findViewById(R.id.variant);
holder.unitView = (TextView) convertView.findViewById(R.id.unit);
holder.quantityView = (TextView) convertView.findViewById(R.id.quantity);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.variantView.setText(listData.get(position).getVariantArray().get(position).toString());
holder.unitView.setText(listData.get(position).getUnitArray().get(position).toString());
holder.quantityView.setText(String.valueOf(listData.get(position).getQuantityRow()));
return convertView;
}
static class ViewHolder {
TextView variantView;
TextView unitView;
TextView quantityView;
}
}
然后，修改数据后，只要致电：
Then, after modifying your data, just call:
customListAdapter.setListData(getListData());
customListAdapter.notifyDataSetChanged();
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