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notifyDataSetChanged无法更新ListView

[英]notifyDataSetChanged fails to update ListView

我有一个DialogFragment,它有一个带CheckedTextView的列表视图和一个顶部的复选框,用于检查和取消选中列表视图中的所有项目。 我试图将CheckedTextView的状态设置为Checked / Unchecked,具体取决于CheckAll复选框的状态。 但是我无法使用notifyDataSetChanged相应地更新视图。 在此输入图像描述

CategoriesDialogFragment.java

public class CategoriesDialogFragment extends SherlockDialogFragment {
    CheckBox checkAll;
    ListView categoriesListView;
    CategoriesListAdapter adapter;
    static Category category;

    String[] categories = new String[] { "Hill Station", "Beach", "Historic",
            "Wild Life", "Waterfall", "River", "Archeology", "Hill Station",
            "Beach", "Historic", "Wild Life", "Waterfall", "River",
            "Archeology" };
    Boolean[] categories_state = new Boolean[] { true, false, true, true, true,
            true, false, true, false, true, true, true, true, false };

    public static CategoriesDialogFragment newInstance() {
        CategoriesDialogFragment frag = new CategoriesDialogFragment();
        Bundle args = new Bundle();
        frag.setArguments(args);
        return frag;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final Dialog dialog = new Dialog(MainActivity.context);
        dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);

        dialog.setContentView(R.layout.dialog_categories);

        categoriesListView = (ListView) dialog
                .findViewById(R.id.listViewDialog);

        List<Category> theCategories = new ArrayList<Category>();
        for (int i = 0; i < categories.length; i++) {
            Boolean flag;
            Category pl = new Category(categories[i], categories_state[i]);
            theCategories.add(pl);
        }

        // categoriesListView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
        adapter = new CategoriesListAdapter(MainActivity.context,
                R.layout.dialog_list_item_category, theCategories);

        categoriesListView.setAdapter(adapter);

        // List View Item Click Listener
        categoriesListView
                .setOnItemClickListener(new AdapterView.OnItemClickListener() {

                    @Override
                    public void onItemClick(AdapterView<?> parent, View view,
                            int position, long id) {
                        // TODO Auto-generated method stub
                        CategoriesListAdapter adapter = (CategoriesListAdapter) parent
                                .getAdapter();
                        Category c = (Category) adapter.getItem(position);
                        c.setChecked(!c.getChecked());
                        adapter.notifyDataSetChanged();
                    }

                });


        // CheckAll CheckBox
        checkAll = (CheckBox) dialog.findViewById(R.id.checkBoxAll);
        checkAll.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {

            @Override
            public void onCheckedChanged(CompoundButton buttonView,
                    boolean isChecked) {

                Toast.makeText(MainActivity.context, "Check",
                        Toast.LENGTH_SHORT).show();
                for (int i = 0; i < adapter.getCount(); i++) {
                    categoriesListView.setItemChecked(i, isChecked);
                    Log.i("Nomad", isChecked + " isChecked " + i);
                }
                adapter.notifyDataSetChanged();

                /*
                 * if (isChecked) { Log.i("Nomad", "isChecked"); for (int i = 0;
                 * i < adapter.getCount(); i++) { category = adapter.getItem(i);
                 * category.setChecked(true); Log.i("Nomad", "isChecked "+i); }
                 * adapter.notifyDataSetChanged(); } else { Log.i("Nomad",
                 * "isUnChecked"); for (int i = 0; i < adapter.getCount(); i++)
                 * { category = adapter.getItem(i); category.setChecked(false);
                 * Log.i("Nomad", "isUnChecked "+i); }
                 * adapter.notifyDataSetChanged(); }
                 */

            }
        });
        return dialog;

    }

    private static class CategoriesListAdapter extends ArrayAdapter<Category> {
        public Context mContext;

        List<Category> mCategories;

        public CategoriesListAdapter(Context context, int resource,
                List<Category> categories) {
            super(context, resource, categories);
            // TODO Auto-generated constructor stub
            this.mCategories = categories;
            this.mContext = context;

        }

        public int getCount() {
            return mCategories.size();
        }

        @Override
        public Category getItem(int position) {
            // TODO Auto-generated method stub
            return mCategories.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {

            ViewHolder holder;

            if (convertView == null) {
                LayoutInflater viewInflater;
                viewInflater = LayoutInflater.from(getContext());
                convertView = viewInflater.inflate(
                        R.layout.dialog_list_item_category, null);

                holder = new ViewHolder();
                holder.categoryName = (CheckedTextView) convertView
                        .findViewById(R.id.categories_checkbox);

                convertView.setTag(holder);

            } else {
                holder = (ViewHolder) convertView.getTag();
            }

            holder.categoryName.setText(mCategories.get(position)
                    .getCategoryName());
            holder.categoryName.setChecked(mCategories.get(position)
                    .getChecked());

            return convertView;
        }

        static class ViewHolder {
            CheckedTextView categoryName;
        }
    }
}

Category.java

public class Category {
    String categoryName = "";
    private boolean checked = false;

    public Category(String categoryName, boolean checked) {

        this.categoryName = categoryName;
        this.checked = checked;

    }

    public String getCategoryName() {
        return categoryName;
    }

    public void setCategoryName(String categoryName) {
        this.categoryName = categoryName;
    }

    public boolean getChecked() {
        return checked;
    }

    public void setChecked(boolean checked) {
        this.checked = checked;
    }

}

dialog_categories.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/parentPanel"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginEnd="8dip"
    android:layout_marginStart="8dip"
    android:background="@color/primary_white"
    android:orientation="vertical" >

    <LinearLayout
        android:id="@+id/title_template"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginEnd="16dip"
        android:layout_marginStart="16dip"
        android:gravity="center_vertical|start"
        android:orientation="horizontal"
        android:paddingTop="5dp" >

        <TextView
            android:id="@+id/textView1"
            style="?android:attr/textAppearanceLarge"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:paddingLeft="10dp"
            android:text="@string/dialog_category_title"
            android:textColor="@color/primary_color"
            android:textSize="22sp" />

        <TextView
            android:id="@+id/all"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/dialog_category_checkbox"
            android:textColor="@color/primary_color" />

        <CheckBox
            android:id="@+id/checkBoxAll"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:paddingRight="6dp" />
    </LinearLayout>

    <View
        android:id="@+id/titleDivider"
        android:layout_width="match_parent"
        android:layout_height="2dip"
        android:background="@color/black" />

    <LinearLayout
        android:id="@+id/contentPanel"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:minHeight="64dp"
        android:orientation="vertical" >

        <ListView
            android:id="@+id/listViewDialog"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" >
        </ListView>
    </LinearLayout>

    <LinearLayout
        android:id="@+id/buttonPanel"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" >

        <Button
            android:id="@+id/button_category_ok"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:text="@string/dialog_category_btn_ok"
            android:textSize="14sp" />
    </LinearLayout>

</LinearLayout>

dialog_list_item_category.xml

<?xml version="1.0" encoding="utf-8"?>
<CheckedTextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/categories_checkbox"
    android:layout_width="fill_parent"
    android:layout_height="?android:attr/listPreferredItemHeight"
    android:checkMark="?android:attr/listChoiceIndicatorMultiple"
    android:gravity="center_vertical"
    android:onClick="toggle"
    android:paddingBottom="10dp"
    android:paddingLeft="10dp"
    android:paddingRight="12dp"
    android:paddingTop="10dp"
    android:text="sss" />

我试图将CheckedTextView的状态设置为Checked / Unchecked,具体取决于CheckAll复选框的状态。 但是我无法使用notifyDataSetChanged相应地更新视图。

添加了一个带有问题代码的示例作为我的答案示例。 它工作, 可以在这里找到 (看看它)。

此外,Android-Developer的答案有效,因为每次用户检查/取消选中所有CheckBoxs时,您基本上都会使用正确的状态重置适配器。 这可能是浪费的(但如果列表相对较小,则可以接受)。 另外请记住,如果Category类的categoryName在对话框中发生变化,您需要确保使用正确的名称构造新Categories (如果您不修改类别名称,那么这不是问题)当所有CheckBox被采取行动时。

尝试这样的事情:

  1. 删除categoriesListView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE); 如果它在你的代码中
  2. 修改OnCheckedChangeListener以检查所有CheckBox如下所示:

      @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { Toast.makeText(getActivity(), "Check", Toast.LENGTH_SHORT) .show(); Log.i("Nomad", "isChecked"); for (int i = 0; i < adapter.getCount(); i++) { adapter.getItem(i).setChecked(isChecked); Log.i("Nomad", "isChecked " + i); } adapter.notifyDataSetChanged(); } 
  3. 将一个OnItemClickListener添加到您的categoriesListView ListView如下所示:

      @Override public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) { CategoriesListAdapter adapter = (CategoriesListAdapter) arg0 .getAdapter(); Category c = (Category) adapter.getItem(arg2); c.setChecked(!c.getCheckStatus()); adapter.notifyDataSetChanged(); } 
  4. setChecked(boolean)getCheckStatus() (我看到你在Category有一个isChecked方法可用于获取布尔状态)是Category类中用于设置和获取该项的状态的方法

  5. 在适配器的getView()方法中,设置如下状态:

     holder.categoryName.setChecked(mCategories.get(position) .getCheckStatus()); 

因此,您正试图在您的项目上设置所有项目

setOnCheckedChangeListener

我认为。 首先,如果你想做你的

adapter.notifyDataSetChanged();

要工作,你必须对你的内容进行编辑。 您正在使用

List<Category> theCategories = new ArrayList<Category>();

要填充对话框并更新它,您必须使用与更改数据相同的对话框或创建新适配器。 要在setOnCheckedChangeListener使用相同的一个,您必须执行以下操作:

checkAll.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {

        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

            if(isChecked){
              theCategories.clear();
              Toast.makeText(MainActivity.context, "Check", Toast.LENGTH_SHORT).show();
              for (int i = 0; i < categories.length; i++) {
                  Category pl = new Category(categories[i], true);
                  theCategories.add(pl);
              }
              adapter.notifyDataSetChanged();
           }

        }
    });

试试这个,现在就告诉我它是否适合你。 :)

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