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我有一个从字符串数组填充的碎片列表视图。我所追求的是当我点击选定的行时，它会变成绿色并保持绿色。只要您不滚动，就可以使用我的作品。只要您滚动尚未选择的行，背景就会发生变化。据我了解，这是由于列表视图回收其视图的方式。我花了很多时间尝试不同的方法来实施以阻止这种情况的发生，但我缺乏如何做到这一点的知识。

public class AreaListFragment extends ListFragment {

private static final String STATE_ACTIVATED_POSITION = "activated_position";
private Callbacks mCallbacks = sDummyCallbacks;
private CentreDataContent mContent;
private int mActivatedPosition = ListView.INVALID_POSITION;

public interface Callbacks {
    public void onItemSelected(String id);
}

private static Callbacks sDummyCallbacks = new Callbacks() {
    @Override
    public void onItemSelected(String id) {
    }
};

public AreaListFragment() {
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    if (mContent == null) {
        Resources res = getResources();
        mContent = new CentreDataContent(R.integer.UnknownID,
                                         res.getStringArray(R.array.undefinedArea),
                                         res.getStringArray(R.array.undefinedChecklist));

        setListAdapter(new ArrayAdapter<CentreDataContent.CentreArea>(
            getActivity(),
            android.R.layout.simple_list_item_activated_1,
            android.R.id.text1,
            CentreDataContent.AREAS));
    }
}

@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);      
    // Restore the previously serialized activated item position.
    if (savedInstanceState != null
            && savedInstanceState.containsKey(STATE_ACTIVATED_POSITION)) {
        setActivatedPosition(savedInstanceState.getInt(STATE_ACTIVATED_POSITION));
    } 
}

@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);
    // Activities containing this fragment must implement its callbacks.
    if (!(activity instanceof Callbacks)) {
        throw new IllegalStateException("Activity must implement fragment's callbacks.");
    }

    mCallbacks = (Callbacks) activity;
}

@Override
public void onDetach() {
    super.onDetach();
    mCallbacks = sDummyCallbacks;
}

@Override
public void onListItemClick(ListView listView, View view, int position, long id) {
    super.onListItemClick(listView, view, position, id);
    view.setBackgroundColor(Color.GREEN);

    mCallbacks.onItemSelected(CentreDataContent.AREAS.get(position).id.toString());

}

@Override
public void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    if (mActivatedPosition != ListView.INVALID_POSITION) {
        // Serialize and persist the activated item position.
        outState.putInt(STATE_ACTIVATED_POSITION, mActivatedPosition);
    }
}

/**
 * Turns on activate-on-click mode. When this mode is on, list items will be
 * given the 'activated' state when touched.
 */
public void setActivateOnItemClick(boolean activateOnItemClick) {
    // When setting CHOICE_MODE_SINGLE, ListView will automatically
    // give items the 'activated' state when touched.
    getListView().setChoiceMode(activateOnItemClick
            ? ListView.CHOICE_MODE_SINGLE
            : ListView.CHOICE_MODE_NONE);
}

private void setActivatedPosition(int position) {
    if (position == ListView.INVALID_POSITION) {
        getListView().setItemChecked(mActivatedPosition, false);
    } else {
        getListView().setItemChecked(position, true);
    }

    mActivatedPosition = position;
}

}

我对android很陌生，正在努力学习。所以这方面的任何帮助都会非常感谢

4

1 回答 1

1

你真正想做的是创建一个背景状态drawable，它会根据行的状态而变化。

例如

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android" >
    <item android:drawable="@drawable/list_pressed_holo" android:state_activated="true"/>
</selector>

正如您在此处看到的，当状态达到activated该特定可绘制对象时

因此，当您单击列表中的某个项目时，您所要做的就是

listview.setItemChecked(position, true);

这将导致您的布局中的根视图被设置为激活并更改背景。

现在，您还必须通过跟踪它并在按下新行时关闭激活状态来管理检查的上一行

listview.setItemChecked(lastPosition, false);

您当然可以将您的列表视图设置为CHOICE_MODE_SINGLE，您不必担心管理上一个单击的项目。

listview.setChoiceMode(ListView.CHOICE_MODE_SINGLE);
于 2013-10-30T16:45:40.663 回答