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我想能夠做到這一點，我已經是我的新編程的代碼請幫助。 - 添加用戶可以點擊的圖標（每個項目）以將其刪除 - 點擊列表中的項目時應該刪除 - 該項目也應該從存儲中刪除（所以下次加載時不會顯示安裝App） 這裏是我的代碼：如何從ListView和sharedpreferences android studio中刪除項目？
MainActivity.java
public class MainActivity extends AppCompatActivity {
private static final String Log_TAG = "ToDoApp";
private ToDoListManager listManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ListView todoList = (ListView) findViewById(R.id.todo_list);
listManager = new ToDoListManager(getApplicationContext());
ToDoItemAdapter adapter = new ToDoItemAdapter(
this,
listManager.getList()
);
ImageButton addButton = (ImageButton) findViewById(R.id.add_item);
addButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
onAddButtonClick();
}
});
}
@Override
protected void onPause() {
super.onPause();
listManager.saveList();
}
private void onAddButtonClick() {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle(R.string.add_item);
final EditText input = new EditText(this);
input.setInputType(InputType.TYPE_CLASS_TEXT);
builder.setView(input);
builder.setPositiveButton(
R.string.ok,
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
ToDoItem item = new ToDoItem(
input.getText().toString(),
false
);
listManager.addItem(item);
}
});
builder.setNegativeButton(
R.string.cancel,
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
builder.show();
}
private class ToDoItemAdapter extends ArrayAdapter<ToDoItem> {
private Context context;
private List<ToDoItem> items;
public ToDoItemAdapter(
Context context,
List<ToDoItem> items
) {
super(context, -1, items);
this.context = context;
this.items = items;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.
getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.to_do_item_layout, parent, false);
}
TextView textView = (TextView) convertView.findViewById(R.id.item);
CheckBox CheckBox = (CheckBox) convertView.findViewById(R.id.CheckBox);
textView.setText(items.get(position).getDescription());
CheckBox.setChecked(items.get(position).isComplete());
convertView.setTag(items.get(position));
convertView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
ToDoItem item = (ToDoItem) v.getTag();
item.toggleComplete();
notifyDataSetChanged();
}
});
return convertView;
}
}
}
todolistmanager.java
public class ToDoListManager {
private static final String APP_PREFERENCES = "todoapp";
private static final String TODO_ITEMS = "itemslist";
private List<ToDoItem> items;
private SharedPreferences savedData;
public ToDoListManager(Context context) {
savedData = context.getSharedPreferences (
APP_PREFERENCES,
Context.MODE_PRIVATE
);
String json = savedData.getString(TODO_ITEMS, null);
if(json == null) {
items = new ArrayList<>();
} else {
Type type = new TypeToken<List<ToDoItem>>() {}.getType();
items = new Gson().fromJson(json, type);
}
}
public List<ToDoItem> getList() {
return items;
}
public void addItem(ToDoItem item) {
items.add(item);
saveList();
}
public void saveList() {
SharedPreferences.Editor edit = savedData.edit();
edit.clear();
String json = new Gson().toJson(items);
edit.putString(TODO_ITEMS, json);
edit.apply();
}
}
todoItem.java
public class ToDoItem {
private String description;
private boolean isComplete;
public ToDoItem(String description,boolean isComplete) {
this.description = description;
this.isComplete = isComplete;
}
public String getDescription() {
return description;
}
public boolean isComplete() {
return isComplete;
}
public void toggleComplete() {
isComplete = !isComplete;
}
@Override
public String toString() {
return getDescription();
}
}
activity_main.xml中
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<EditText
android:id="@+id/txtItem"
android:layout_width="240dp"
android:layout_height="wrap_content"
android:inputType="text"
android:hint="@string/hintTxtItem"
/>
<Button
android:id="@+id/btnAdd"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/lblBtnAdd"
android:layout_toRightOf="@id/txtItem"
/>
<TextView
android:id="@android:id/empty"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/txtItem"
android:text="@string/txtEmpty"
android:gravity="center_horizontal"
/>
<ListView
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/txtItem"
android:choiceMode="multipleChoice" >
</ListView>
<Button
android:id="@+id/btnDel"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="@string/lblBtnDel" />
to_do_item_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:weightSum="1">
<CheckBox
android:id="@+id/CheckBox"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="@+id/item"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="20sp"/>
<ListView
android:layout_weight="20"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<Button
android:id="@+id/btnDel"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="@string/lblBtnDel" />
非常感謝你，但我希望你能夠在不改變我的大部分原始編碼的情況下展示我，因爲這對我來說很容易理解，如果你使用我的代碼。你能告訴我如何使刪除按鈕的工作？ （使用我的代碼購買）非常感謝你:) –
您可以關注的兩個問題：1.刪除列表中的項目。 2.通過adapter.notifyDataSetChanged（）方法更新適配器。 – sonnv1368
你能告訴我在哪裏植入我的代碼刪除按鈕？ –