【发布时间】:2018-11-20 20:04:37
【问题描述】:
我有一个片段,我想在其中实现一个动态列表,以便您可以按下一个按钮来在列表中添加字段。
我找到了一些代码来做到这一点(如下所示)
Dynamically add elements to a listView Android
我正在尝试在我的片段中实现这一点,但没有成功。一个解决方案将不胜感激。
我找到的用于制作动态列表的代码
import java.util.ArrayList;
import java.util.List;
import android.app.ListActivity;
import android.widget.ArrayAdapter;
import android.os.Bundle;
import android.view.View;
public class OrdersDynamicList extends ListActivity {
//LIST OF ARRAY STRINGS WHICH WILL SERVE AS LIST ITEMS
ArrayList<String> listItems=new ArrayList<String>();
//DEFINING A STRING ADAPTER WHICH WILL HANDLE THE DATA OF THE LISTVIEW
ArrayAdapter<String> adapter;
//RECORDING HOW MANY TIMES THE BUTTON HAS BEEN CLICKED
int clickCounter=0;
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.activity_server);
adapter=new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1,
listItems);
setListAdapter(adapter);
}
//METHOD WHICH WILL HANDLE DYNAMIC INSERTION
public void addItems(View v) {
listItems.add("Clicked : "+clickCounter++);
adapter.notifyDataSetChanged();
}
}
我的片段
import android.content.Context;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
public class FragmentNewTable extends Fragment {
private FragmentNewTableListener listener;
private OrdersDynamicList ordersDynamicList;
public interface FragmentNewTableListener {
void onInputFragmentNewTableSent(CharSequence input);
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_new_table, container, false);
return v;
}
public void updateEditText(CharSequence newText) {
//editText.setText(newText);
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof FragmentNewTableListener) {
listener = (FragmentNewTableListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement FragmentAListener");
}
}
@Override
public void onDetach() {
super.onDetach();
listener = null;
}
片段 XML
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<Button
android:id="@+id/addBtn"
android:text="Add New Order"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:onClick="addItems"/>
<ListView
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:drawSelectorOnTop="false"
/>
</LinearLayout>
【问题讨论】:
-
从技术上讲,您有 2 个
ListViews。一个在活动 [ListActivityactivity_server] 中,另一个在片段中。您正在设置、更新和通知附加到 Activity 的适配器。进行简单的活动AppCompatActivity并将addItem移动到Fragment类。
标签: java android android-fragments android-listview