Question

我正在创建一个由数据库动态填充的交换机ListView。我需要验证是否至少选择了其中一个，并启用/禁用继续按钮。我将开关的值存储在HashMap中，以便我可以轻松检查它是否包含真值。

开关是在CursorAdapter中创建的，我尝试过设置OnClickListener和OnCheckedChangeListener。两者似乎都是，当单击一个项目时，监听器将触发列表中的每个按钮，然后我在HashMap中存储的值将被列表中下方按钮的已检查状态覆盖。

class LanguageInstallAdapter extends CursorAdapter {

    private final String LOG_TAG = LanguageInstallAdapter.class.getSimpleName();
    public HashMap<String,Boolean> mDBValues = new HashMap<String,Boolean>(); //original DB values
    public HashMap<String,Boolean> mChangedValues = new HashMap<String,Boolean>();//anything changed
    private HashMap<String,Boolean> mAllCurrentValues= new HashMap<String,Boolean>(); //complete current
    private View mRootView;

    public static class ViewHolder {
        public final TextView nameView;
        public final SwitchCompat installSwitch;

        public ViewHolder(View view) {
            nameView = (TextView) view.findViewById(R.id.language_textview);
            installSwitch = (SwitchCompat) view.findViewById(R.id.installed_switch);
        }
    }

    public LanguageInstallAdapter(Context context, Cursor c, int flags, View root) {
        super(context, c, flags);
        mRootView = root;
    }

    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        View view = LayoutInflater.from(context).inflate(R.layout.list_item_install_language, parent, false);
        ViewHolder viewHolder = new ViewHolder(view);
        view.setTag(viewHolder);
        return view;
    }

    @Override
    public void bindView(View view, final Context context, final Cursor cursor) {
        ViewHolder viewHolder = (ViewHolder) view.getTag();
        String languageId = cursor.getString(LanguageInstallFragment.COL_ID);
        String name = cursor.getString(LanguageInstallFragment.COL_NAME);
        boolean langInstalled = cursor.getInt(LanguageInstallFragment.COL_INSTALLED)>0; //convert DB 1 or 0 to java boolean
        mDBValues.put(languageId, langInstalled);
        mAllCurrentValues.put(languageId, langInstalled);
        viewHolder.nameView.setText(name);
        viewHolder.installSwitch.setChecked(langInstalled);
        viewHolder.installSwitch.setTag(languageId);
        viewHolder.installSwitch.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                CompoundButton button = (CompoundButton) v;
                String buttonLang= (String) button.getTag();
                mChangedValues.put(buttonLang, button.isChecked());
                mAllCurrentValues.put(buttonLang, button.isChecked());
                setSubmitButton();
            }
        });
    }

    public void setSubmitButton(){

        for (Map.Entry<String,Boolean> entry : mAllCurrentValues.entrySet()) {
            Log.d(LOG_TAG, "Hashmap: " + entry.getKey() + " " + entry.getValue());
        }

        if(mAllCurrentValues.containsValue(true)) {
            mRootView.findViewById(R.id.submit_button).setEnabled(true);
            mRootView.findViewById(R.id.lang_prompt).setVisibility(View.GONE);
        } else {
            mRootView.findViewById(R.id.submit_button).setEnabled(false);
            mRootView.findViewById(R.id.lang_prompt).setVisibility(View.VISIBLE);
        }
    }
}

从一系列选择中记录输出：

Initial state (none selected)
09-07 20:21:29.445  ﹕ Hashmap: 4 false
09-07 20:21:29.445  ﹕ Hashmap: 2 false
09-07 20:21:29.445  ﹕ Hashmap: 3 false

Select 2 (1 selected)
09-07 20:22:42.096  ﹕ Hashmap: 4 false
09-07 20:22:42.096  ﹕ Hashmap: 2 true
09-07 20:22:42.096  ﹕ Hashmap: 3 false

Select 3 (2 selected)
09-07 20:23:28.192  ﹕ Hashmap: 4 false
09-07 20:23:28.192  ﹕ Hashmap: 2 false
09-07 20:23:28.192  ﹕ Hashmap: 3 true

Select 4 (3 selected)
09-07 20:23:43.608  ﹕ Hashmap: 4 true
09-07 20:23:43.608  ﹕ Hashmap: 2 false
09-07 20:23:43.608  ﹕ Hashmap: 3 true

Unselect 2 (2 selected)
09-07 20:23:58.507  ﹕ Hashmap: 4 true
09-07 20:23:58.507  ﹕ Hashmap: 2 false
09-07 20:23:58.507  ﹕ Hashmap: 3 false

Unselect 3 (1 selected)
09-07 20:24:13.942  ﹕ Hashmap: 4 false
09-07 20:24:13.942  ﹕ Hashmap: 2 false
09-07 20:24:13.942  ﹕ Hashmap: 3 false

有没有办法不在每个按钮上调用监听器？即使调用每个按钮，为什么值被错误地覆盖？对于每个按钮的调用是否仍然不能获取该按钮的languageId和isChecked值，而不是覆盖另一个按钮？有没有更好的方法来做到这一点？

Answer 1

替换此行

window.onload

与

mAllCurrentValues.put(languageId, langInstalled);

SwitchCompat onClickListener调用了组

1 个答案: