Android的微调有多种选择 [英] Android Spinner with multiple choice

问题描述

如何创建微调，允许选择多个项目？

How do I create spinner which allows to choose multiple items?

推荐答案

我已经写了自定义实现MultiSpinner的。它看起来像正常的微调，但它的复选框，而不是单选按钮。选择的值显示在微调以逗号分隔。所有的值都默认为选中。试试吧：

I have written custom implementation of MultiSpinner. It's looking similar to normal spinner, but it has checkboxes instead of radiobuttons. Selected values are displayed on the spinner divided by comma. All values are checked by default. Try it:

package cz.destil.settleup.gui;

public class MultiSpinner extends Spinner implements
        OnMultiChoiceClickListener, OnCancelListener {

    private List<String> items;
    private boolean[] selected;
    private String defaultText;
    private MultiSpinnerListener listener;

    public MultiSpinner(Context context) {
        super(context);
    }

    public MultiSpinner(Context arg0, AttributeSet arg1) {
        super(arg0, arg1);
    }

    public MultiSpinner(Context arg0, AttributeSet arg1, int arg2) {
        super(arg0, arg1, arg2);
    }

    @Override
    public void onClick(DialogInterface dialog, int which, boolean isChecked) {
        if (isChecked)
            selected[which] = true;
        else
            selected[which] = false;
    }

    @Override
    public void onCancel(DialogInterface dialog) {
        // refresh text on spinner
        StringBuffer spinnerBuffer = new StringBuffer();
        boolean someUnselected = false;
        for (int i = 0; i < items.size(); i++) {
            if (selected[i] == true) {
                spinnerBuffer.append(items.get(i));
                spinnerBuffer.append(", ");
            } else {
                someUnselected = true;
            }
        }
        String spinnerText;
        if (someUnselected) {
            spinnerText = spinnerBuffer.toString();
            if (spinnerText.length() > 2)
                spinnerText = spinnerText.substring(0, spinnerText.length() - 2);
        } else {
            spinnerText = defaultText;
        }
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(getContext(),
                android.R.layout.simple_spinner_item,
                new String[] { spinnerText });
        setAdapter(adapter);
        listener.onItemsSelected(selected);
    }

    @Override
    public boolean performClick() {
        AlertDialog.Builder builder = new AlertDialog.Builder(getContext());
        builder.setMultiChoiceItems(
                items.toArray(new CharSequence[items.size()]), selected, this);
        builder.setPositiveButton(android.R.string.ok,
                new DialogInterface.OnClickListener() {

                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.cancel();
                    }
                });
        builder.setOnCancelListener(this);
        builder.show();
        return true;
    }

    public void setItems(List<String> items, String allText,
            MultiSpinnerListener listener) {
        this.items = items;
        this.defaultText = allText;
        this.listener = listener;

        // all selected by default
        selected = new boolean[items.size()];
        for (int i = 0; i < selected.length; i++)
            selected[i] = true;

        // all text on the spinner
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(getContext(),
                android.R.layout.simple_spinner_item, new String[] { allText });
        setAdapter(adapter);
    }

    public interface MultiSpinnerListener {
        public void onItemsSelected(boolean[] selected);
    }
}

您使用它在XML这样的：

You use it in XML like this:

<cz.destil.settleup.gui.MultiSpinner android:id="@+id/multi_spinner" />

和传递数据给它在Java中是这样的：

And you pass data to it in Java like this:

MultiSpinner multiSpinner = (MultiSpinner) findViewById(R.id.multi_spinner);
multiSpinner.setItems(items, getString(R.string.for_all), this);

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