android - 如何在 MultiSelection Spinner Android 中超过限制后禁用项目选择

Question

我试图在超过限制后取消选择。在下面给出的代码中，当最大选择限制超过时，我能够实现 toast 。但是当我试图在超过限制时禁用或取消选择该项目时，它不是工作。

public class MultiSelectionSpinner1 extends Spinner implements
        OnMultiChoiceClickListener {

    public interface OnMultipleItemsSelectedListener{
        void selectedIndices(List<Integer> indices);
        void selectedStrings(List<String> strings);
    }
    private OnMultipleItemsSelectedListener listener;

    String[] _items = null;
    boolean[] mSelection = null;
    boolean[] mSelectionAtStart = null;
    String _itemsAtStart = null;

    ArrayAdapter<String> simple_adapter;

    public MultiSelectionSpinner1(Context context) {
        super(context);
        simple_adapter = new ArrayAdapter<>(context,
                android.R.layout.simple_spinner_item);
        super.setAdapter(simple_adapter);
    }

    public MultiSelectionSpinner1(Context context, AttributeSet attrs) {
        super(context, attrs);

        simple_adapter = new ArrayAdapter<>(context,
                android.R.layout.simple_spinner_item);
        super.setAdapter(simple_adapter);
    }

    public void setListener(OnMultipleItemsSelectedListener listener){
        this.listener = listener;
    }

    public void onClick(DialogInterface dialog, int which, boolean isChecked) {
        if (mSelection != null && which < mSelection.length) {
            Log.e("_items.length", "_items.length" + _items.length);
            Log.e("_itemsAtStart", "_itemsAtStart" + _itemsAtStart);


//            listener.selectedStrings(getSelectedStrings());
            if(getSelectedIndices().size()<3){
                mSelection[which] = isChecked;
                simple_adapter.clear();
                simple_adapter.add(buildSelectedItemString());
            }else
            {
                Toast.makeText(getContext(),"Exceeds",Toast.LENGTH_SHORT).show();
                setDiselection(which);

            }
            //listener.selectedIndices(getSelectedIndices());
        } else {
            throw new IllegalArgumentException(
                    "Argument 'which' is out of bounds.");
        }
    }


    @Override
    public boolean performClick() {
        AlertDialog.Builder builder = new AlertDialog.Builder(getContext());
        builder.setTitle("Please select!!!");
        builder.setMultiChoiceItems(_items, mSelection, this);
        _itemsAtStart = getSelectedItemsAsString();
        builder.setPositiveButton("Submit", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                System.arraycopy(mSelection, 0, mSelectionAtStart, 0, mSelection.length);
                listener.selectedIndices(getSelectedIndices());
                listener.selectedStrings(getSelectedStrings());
            }
        });
        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                simple_adapter.clear();
                simple_adapter.add(_itemsAtStart);
                System.arraycopy(mSelectionAtStart, 0, mSelection, 0, mSelectionAtStart.length);
            }
        });
        builder.show();
        return true;
    }

    @Override
    public void setAdapter(SpinnerAdapter adapter) {
        throw new RuntimeException(
                "setAdapter is not supported by MultiSelectSpinner.");
    }

    public void setItems(String[] items) {
        _items = items;
        mSelection = new boolean[_items.length];
        mSelectionAtStart = new boolean[_items.length];
        simple_adapter.clear();
        simple_adapter.add(_items[0]);
        Arrays.fill(mSelection, false);
        mSelection[0] = true;
        mSelectionAtStart[0] = true;
    }

    public void setItems(List<String> items) {
        _items = items.toArray(new String[items.size()]);
        mSelection = new boolean[_items.length];
        mSelectionAtStart  = new boolean[_items.length];
        simple_adapter.clear();
        simple_adapter.add(_items[0]);
        Arrays.fill(mSelection, false);
        mSelection[0] = true;
    }

    public void setSelection(String[] selection) {
        for (int i = 0; i < mSelection.length; i++) {
            mSelection[i] = false;
            mSelectionAtStart[i] = false;
        }
        for (String cell : selection) {
            for (int j = 0; j < _items.length; ++j) {
                if (_items[j].equals(cell)) {
                    mSelection[j] = true;
                    mSelectionAtStart[j] = true;
                }
            }
        }
        simple_adapter.clear();
        simple_adapter.add(buildSelectedItemString());
    }

    public void setSelection(List<String> selection) {
        for (int i = 0; i < mSelection.length; i++) {
            mSelection[i] = false;
            mSelectionAtStart[i] = false;
        }
        for (String sel : selection) {
            for (int j = 0; j < _items.length; ++j) {
                if (_items[j].equals(sel)) {
                    mSelection[j] = true;
                    mSelectionAtStart[j] = true;
                }
            }
        }
        simple_adapter.clear();
        simple_adapter.add(buildSelectedItemString());
    }

    public void setSelection(int index) {
        for (int i = 0; i < mSelection.length; i++) {
            mSelection[i] = false;
            mSelectionAtStart[i] = false;
        }
        if (index >= 0 && index < mSelection.length) {
            mSelection[index] = true;
            mSelectionAtStart[index] = true;
        } else {
            throw new IllegalArgumentException("Index " + index
                    + " is out of bounds.");
        }
        simple_adapter.clear();
        simple_adapter.add(buildSelectedItemString());
    }

    public void setDiselection(int index) {

        if (index >= 0 && index < mSelection.length) {
            mSelection[index] = false;
            mSelectionAtStart[index] = false;

        } else {
            throw new IllegalArgumentException("Index " + index
                    + " is out of bounds.");
        }
        simple_adapter.clear();
        simple_adapter.notifyDataSetChanged();
        simple_adapter.add(buildSelectedItemString());
    }

    public void setSelection(int[] selectedIndices) {
        for (int i = 0; i < mSelection.length; i++) {
            mSelection[i] = false;
            mSelectionAtStart[i] = false;
        }
        for (int index : selectedIndices) {
            if (index >= 0 && index < mSelection.length) {
                mSelection[index] = true;
                mSelectionAtStart[index] = true;
            } else {
                throw new IllegalArgumentException("Index " + index
                        + " is out of bounds.");
            }
        }
        simple_adapter.clear();
        simple_adapter.add(buildSelectedItemString());
    }

    public List<String> getSelectedStrings() {
        List<String> selection = new LinkedList<>();
        for (int i = 0; i < _items.length; ++i) {
            if (mSelection[i]) {
                selection.add(_items[i]);
            }
        }
        return selection;
    }

    public List<Integer> getSelectedIndices() {
        List<Integer> selection = new LinkedList<>();
        for (int i = 0; i < _items.length; ++i) {
            if (mSelection[i]) {
                selection.add(i);
            }
        }
        return selection;
    }

    private String buildSelectedItemString() {
        StringBuilder sb = new StringBuilder();
        boolean foundOne = false;

        for (int i = 0; i < _items.length; ++i) {
            if (mSelection[i]) {
                if (foundOne) {
                    sb.append(", ");
                }
                foundOne = true;

                sb.append(_items[i]);
            }
        }
        return sb.toString();
    }

    public String getSelectedItemsAsString() {
        StringBuilder sb = new StringBuilder();
        boolean foundOne = false;

        for (int i = 0; i < _items.length; ++i) {
            if (mSelection[i]) {
                if (foundOne) {
                    sb.append(", ");
                }
                foundOne = true;
                sb.append(_items[i]);
            }
        }
        return sb.toString();
    }
}

Answer 1

试试这个。我修改了您的 public void setDeselection(int index) 和 public boolean performClick() 方法。

public class MultiSelectSpinner1 extends Spinner implements
    DialogInterface.OnMultiChoiceClickListener {

    private static final String TAG = MultiSelectSpinner1.class.getSimpleName();
    String[] _items = null;
    boolean[] mSelection = null;
    boolean[] mSelectionAtStart = null;
    String _itemsAtStart = null;

    ArrayAdapter<String> simple_adapter;
    private OnMultipleItemsSelectedListener listener;

    AlertDialog alertDialog;

    public MultiSelectSpinner1(Context context) {
        super(context);
        simple_adapter = new ArrayAdapter<>(context,
            android.R.layout.simple_spinner_item);
        super.setAdapter(simple_adapter);
    }

    public MultiSelectSpinner1(Context context, AttributeSet attrs) {
        super(context, attrs);

        simple_adapter = new ArrayAdapter<>(context,
            android.R.layout.simple_spinner_item);
        super.setAdapter(simple_adapter);
    }

    public void setListener(OnMultipleItemsSelectedListener listener)
    {
        this.listener = listener;
    }

    public void onClick(DialogInterface dialog, int which, boolean isChecked) {
        if (mSelection != null && which < mSelection.length) {
            Log.e("_items.length", "_items.length" + _items.length);
            Log.e("_itemsAtStart", "_itemsAtStart" + _itemsAtStart);


            if (getSelectedIndices().size() < 3) {
                mSelection[which] = isChecked;
                simple_adapter.clear();
                simple_adapter.add(buildSelectedItemString());
            } else {
                Toast.makeText(getContext(),"Exceeds",Toast.LENGTH_SHORT).show();
                setDeselection(which);

            }
        } else {
            throw new IllegalArgumentException(
                "Argument 'which' is out of bounds.");
        }
    }

    @Override
    public boolean performClick() {
        buildDialogue();
        return true;
    }

    private void buildDialogue() {
        if(alertDialog!=null&&alertDialog.isShowing())
            alertDialog.dismiss();

        AlertDialog.Builder builder = new      AlertDialog.Builder(getContext());
        builder.setTitle("Please select!!!");
        builder.setMultiChoiceItems(_items, mSelection, this);
        _itemsAtStart = getSelectedItemsAsString();
        builder.setPositiveButton("Submit", new  DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                System.arraycopy(mSelection, 0, mSelectionAtStart, 0, mSelection.length);
                if (listener != null) {
                    listener.selectedIndices(getSelectedIndices());
                    listener.selectedStrings(getSelectedStrings());
                }
            }
        });
        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                simple_adapter.clear();
                simple_adapter.add(_itemsAtStart);
                System.arraycopy(mSelectionAtStart, 0, mSelection, 0, mSelectionAtStart.length);
            }
        });
        alertDialog = builder.create();
        alertDialog.show();
    }

    @Override
    public void setAdapter(SpinnerAdapter adapter) {
        throw new RuntimeException(
            "setAdapter is not supported by MultiSelectSpinner.");
    }

    public void setItems(String[] items) {
        _items = items;
        mSelection = new boolean[_items.length];
        mSelectionAtStart = new boolean[_items.length];
        simple_adapter.clear();
        simple_adapter.add(_items[0]);
        Arrays.fill(mSelection, false);
        mSelection[0] = true;
        mSelectionAtStart[0] = true;
    }

    public void setItems(List<String> items) {
        _items = items.toArray(new String[items.size()]);
        mSelection = new boolean[_items.length];
        mSelectionAtStart = new boolean[_items.length];
        simple_adapter.clear();
        simple_adapter.add(_items[0]);
        Arrays.fill(mSelection, false);
        mSelection[0] = true;
    }

    public void setSelection(String[] selection) {
        for (int i = 0; i < mSelection.length; i++) {
            mSelection[i] = false;
            mSelectionAtStart[i] = false;
        }
        for (String cell : selection) {
            for (int j = 0; j < _items.length; ++j) {
                if (_items[j].equals(cell)) {
                    mSelection[j] = true;
                    mSelectionAtStart[j] = true;
                }
            }
        }
        simple_adapter.clear();
        simple_adapter.add(buildSelectedItemString());
    }

    public void setSelection(List<String> selection) {
        for (int i = 0; i < mSelection.length; i++) {
            mSelection[i] = false;
           mSelectionAtStart[i] = false;
        }
        for (String sel : selection) {
            for (int j = 0; j < _items.length; ++j) {
                if (_items[j].equals(sel)) {
                    mSelection[j] = true;
                    mSelectionAtStart[j] = true;
                }
            }
        }
        simple_adapter.clear();
        simple_adapter.add(buildSelectedItemString());
    }

    public void setSelection(int index) {
        for (int i = 0; i < mSelection.length; i++) {
            mSelection[i] = false;
            mSelectionAtStart[i] = false;
        }
        if (index >= 0 && index < mSelection.length) {
            mSelection[index] = true;
            mSelectionAtStart[index] = true;
        } else {
            throw new IllegalArgumentException("Index " + index
                + " is out of bounds.");
        }
        simple_adapter.clear();
        simple_adapter.add(buildSelectedItemString());
    }

    public void setDeselection(int index) {
        Log.d(TAG, "setDeselection() called with: " + "index = [" + index + "]");

        if (index >= 0 && index < mSelection.length) {
            mSelection[index] = false;
            mSelectionAtStart[index] = false;

        } else {
             throw new IllegalArgumentException("Index " + index
                + " is out of bounds.");
        }
        simple_adapter.clear();
        simple_adapter.notifyDataSetChanged();
        simple_adapter.add(buildSelectedItemString());

        buildDialogue();
    }

    public void setSelection(int[] selectedIndices) {
        for (int i = 0; i < mSelection.length; i++) {
            mSelection[i] = false;
            mSelectionAtStart[i] = false;
        }
        for (int index : selectedIndices) {
            if (index >= 0 && index < mSelection.length) {
                mSelection[index] = true;
                mSelectionAtStart[index] = true;
            } else {
                throw new IllegalArgumentException("Index " + index
                    + " is out of bounds.");
            }
        }
        simple_adapter.clear();
        simple_adapter.add(buildSelectedItemString());
    }

    public List<String> getSelectedStrings() {
        List<String> selection = new LinkedList<>();
        for (int i = 0; i < _items.length; ++i) {
            if (mSelection[i]) {
                selection.add(_items[i]);
            }
        }
        return selection;
    }

    public List<Integer> getSelectedIndices() {
        List<Integer> selection = new LinkedList<>();
        for (int i = 0; i < _items.length; ++i) {
            if (mSelection[i]) {
                selection.add(i);
            }
        }
        return selection;
    }

    private String buildSelectedItemString() {
        StringBuilder sb = new StringBuilder();
        boolean foundOne = false;

        for (int i = 0; i < _items.length; ++i) {
            if (mSelection[i]) {
                if (foundOne) {
                    sb.append(", ");
                }
                foundOne = true;

                sb.append(_items[i]);
            }
        }
        return sb.toString();
    }

    public String getSelectedItemsAsString() {
        StringBuilder sb = new StringBuilder();
        boolean foundOne = false;

        for (int i = 0; i < _items.length; ++i) {
            if (mSelection[i]) {
                if (foundOne) {
                    sb.append(", ");
                }
                foundOne = true;
                sb.append(_items[i]);
            }
        }
        return sb.toString();
    }

    public interface OnMultipleItemsSelectedListener {
        void selectedIndices(List<Integer> indices);

        void selectedStrings(List<String> strings);
    }
}