如何使用单选复选框android在AlertDialog中选择条目？

| 我有一个带有单选列表和两个按钮的警报对话框：一个“ 0”按钮和一个“ 1”按钮。下面的代码显示了我如何实现它。

private final Dialog createListFile(final String[] fileList) {
  AlertDialog.Builder builder = new AlertDialog.Builder(this);
  builder.setTitle(\"Compare with:\");

  builder.setSingleChoiceItems(fileList, -1, new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int whichButton) {
      Log.d(TAG,\"The wrong button was tapped: \" + fileList[whichButton]);
    }
  });

  builder.setPositiveButton(\"OK\", new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int whichButton) {}
  });

  builder.setNegativeButton(\"Cancel\", new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int whichButton) {}
  });

  return builder.create();
}

我的目标是在轻按“ 0”按钮时获得所选单选按钮的名称。我试图将字符串保存在变量中，但是在内部类内部，只能访问最终变量。有没有一种方法可以避免使用最终变量来存储所选的单选按钮？

已邀请:

5 个回复

响摔衅幸

使用最终变量显然是行不通的（因为在声明时只能分配一次）。所谓的\“ global \”变量通常是代码的味道（尤其是当它们成为Activity类的一部分时，通常在其中创建AlertDialogs）。较干净的解决方案是将DialogInterface对象转换为AlertDialog，然后调用getListView（）。getCheckedItemPosition（）。像这样：

new AlertDialog.Builder(this)
        .setSingleChoiceItems(items, 0, null)
        .setPositiveButton(R.string.ok_button_label, new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int whichButton) {
                dialog.dismiss();
                int selectedPosition = ((AlertDialog)dialog).getListView().getCheckedItemPosition();
                // Do something useful withe the position of the selected radio button
            }
        })
        .show();

究补闯

这已经很好地回答了，但是我一直从Google那里找到这个答案，我想分享一个非匿名的类解决方案。我本人更喜欢可重用的类，可能会对其他人有所帮助。在此示例中，我使用DialogFragment实现，并通过回调方法检索值。可以通过创建公共接口来完成从Dialog获取值的回调方法。

public interface OnDialogSelectorListener {
    public void onSelectedOption(int selectedIndex);
}

同样，“ 5”实现了“ 8”，这意味着您可以将已实现的类注册为正在创建的“ 5”的OnClickListener。例如

public Dialog onCreateDialog(Bundle savedInstanceState) {
    final AlertDialog.Builder builder = new AlertDialog.Builder(this.getActivity());

    builder.setTitle(R.string.select);
    builder.setSingleChoiceItems(mResourceArray, mSelectedIndex, this);
    builder.setPositiveButton(R.string.ok, this);
    builder.setNegativeButton(R.string.cancel, this);
    return builder.create();
}

线 builder.setSingleChoiceItems(mResourceArray, mSelectedIndex, this); 创建一个选择对话框，其中包含来自mResourceArray中存储的资源数组中的选项。这还将从mSelectedIndex中存储的内容中预选择一个选项索引，最后将ѭ12本身设置为OnClickListener。（如果本段有点令人困惑，请在最后查看完整代码）现在，您可以在OnClick方法中获取对话框中的值

@Override
public void onClick(DialogInterface dialog, int which) {

    switch (which) {
        case Dialog.BUTTON_NEGATIVE: // Cancel button selected, do nothing
            dialog.cancel();
            break;

        case Dialog.BUTTON_POSITIVE: // OK button selected, send the data back
            dialog.dismiss();
            // message selected value to registered callbacks with the
                    // selected value.
            mDialogSelectorCallback.onSelectedOption(mSelectedIndex);
            break;

        default: // choice item selected
                    // store the new selected value in the static variable
            mSelectedIndex = which;
            break;
    }
}

这里发生的是，当一个项目被选中时，它存储在一个变量中。如果用户单击“取消”按钮，则不会发送任何更新，也不会进行任何更改。如果用户单击“确定”按钮，它将通过创建的回调将值返回到创建它的ѭ14。例如，以下是从FragmentActivity创建对话框的方法。

final SelectorDialog sd = SelectorDialog.newInstance(R.array.selector_array, preSelectedValue);
sd.show(getSupportFragmentManager(), TAG);

在这里，资源数组_R.array.selector_array_是要在对话框中显示的字符串数组，而preSelectedValue是在打开时选择的索引。最后，您的FragmentActivity将实现OnDialogSelectorListener并将收到回调消息。

public class MyActivity extends FragmentActivity implements OnDialogSelectorListener {
// ....

    public void onSelectedOption(int selectedIndex) {
        // do something with the newly selected index
    }
}

我希望这对某人有帮助，因为我花了很多时间来理解它。这是带有回调的ѭ5full的完整实现。

public class SelectorDialog extends DialogFragment implements OnClickListener {
    static final String TAG = \"SelectorDialog\";

    static int mResourceArray;
    static int mSelectedIndex;
    static OnDialogSelectorListener mDialogSelectorCallback;

    public interface OnDialogSelectorListener {
        public void onSelectedOption(int dialogId);
    }

    public static DialogSelectorDialog newInstance(int res, int selected) {
        final DialogSelectorDialog dialog  = new DialogSelectorDialog();
        mResourceArray = res;
        mSelectedIndex = selected;

        return dialog;
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);

        try {
            mDialogSelectorCallback = (OnDialogSelectorListener)activity;
        } catch (final ClassCastException e) {
            throw new ClassCastException(activity.toString() + \" must implement OnDialogSelectorListener\");
        }
    }

    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final AlertDialog.Builder builder = new AlertDialog.Builder(this.getActivity());

        builder.setTitle(R.string.select);
        builder.setSingleChoiceItems(mResourceArray, mSelectedIndex, this);
        builder.setPositiveButton(R.string.ok, this);
        builder.setNegativeButton(R.string.cancel, this);
        return builder.create();
    }

    @Override
    public void onClick(DialogInterface dialog, int which) {

        switch (which) {
            case Dialog.BUTTON_NEGATIVE:
                dialog.cancel();
                break;

            case Dialog.BUTTON_POSITIVE:
                dialog.dismiss();
                // message selected value to registered calbacks
                mDialogSelectorCallback.onSelectedOption(mSelectedIndex);
                break;

            default: // choice selected click
                mSelectedIndex = which;
                break;
        }

    }
}

来自注释的问题如何用Fragment而不是ѭ14call称呼它。首先对ѭ5进行一些更改。删除“ 25”事件，因为在这种情况下这不是最简单的方法。添加新方法以添加对回调的引用

public void setDialogSelectorListener (OnDialogSelectorListener listener) {
    this.mListener = listener;
}

在您的ѭ22中实现监听器

public class MyFragment extends Fragment implements SelectorDialog.OnDialogSelectorListener {
// ....

    public void onSelectedOption(int selectedIndex) {
        // do something with the newly selected index
    }
}

现在创建一个新实例，并将引用传递给“ 22”以使用它。

final SelectorDialog sd = SelectorDialog.newInstance(R.array.selector_array, preSelectedValue);
// this is a reference to MyFragment
sd.setDialogSelectorListener(this);
// mActivity is just a reference to the activity attached to MyFragment
sd.show(this.mActivity.getSupportFragmentManager(), TAG);

广躺椽

final CharSequence[] choice = {\"Choose from Gallery\",\"Capture a photo\"};

int from; //This must be declared as global !

AlertDialog.Builder alert = new AlertDialog.Builder(activity);
alert.setTitle(\"Upload Photo\");
alert.setSingleChoiceItems(choice, -1, new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int which) {
        if (choice[which] == \"Choose from Gallery\") {
            from = 1;
        } else if (choice[which] == \"Capture a photo\") {
            from = 2;
        }
    }
});
alert.setPositiveButton(\"OK\", new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int which) {
        if (from == 0) {
            Toast.makeText(activity, \"Select One Choice\", 
                        Toast.LENGTH_SHORT).show();
        } else if (from == 1) {
            // Your Code
        } else if (from == 2) {
            // Your Code
        }
    }
});
alert.show();

庞协腿宛炯

正如其他人指出的那样，实现\'com.google.android.material：material：1.0.0 \'更简单有关更多信息，请参阅此材料指南。 https://material.io/develop/android/docs/getting-started/

CharSequence[] choices = {\"Choice1\", \"Choice2\", \"Choice3\"};
boolean[] choicesInitial = {false, true, false};
AlertDialog.Builder alertDialogBuilder = new MaterialAlertDialogBuilder(getContext())
    .setTitle(title)
    .setPositiveButton(\"Accept\", null)
    .setNeutralButton(\"Cancel\", null)
    .setMultiChoiceItems(choices, choicesInitial, new DialogInterface.OnMultiChoiceClickListener() {
      @Override
      public void onClick(DialogInterface dialog, int which, boolean isChecked) {

      }
    });
alertDialogBuilder.show();

笛驮型迸

尝试这个。

final String[] fonts = {\"Small\", \"Medium\", \"Large\", \"Huge\"};

AlertDialog.Builder builder = new AlertDialog.Builder(TopicDetails.this);
builder.setTitle(\"Select a text size\");
builder.setItems(fonts, new DialogInterface.OnClickListener() {
  @Override
  public void onClick(DialogInterface dialog, int which) {
    if (\"Small\".equals(fonts[which])) {
      Toast.makeText(MainActivity.this,\"you nailed it\", Toast.LENGTH_SHORT).show();
    }
    else if (\"Medium\".equals(fonts[which])) {
      Toast.makeText(MainActivity.this,\"you cracked it\", Toast.LENGTH_SHORT).show();
    }
    else if (\"Large\".equals(fonts[which])){
      Toast.makeText(MainActivity.this,\"you hacked it\", Toast.LENGTH_SHORT).show();
    }
    else if (\"Huge\".equals(fonts[which])){
     Toast.makeText(MainActivity.this,\"you digged it\", Toast.LENGTH_SHORT).show();
    }
  // the user clicked on colors[which]
  }
});
builder.show();

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如何使用单选复选框android在AlertDialog中选择条目？

5 个回复

发起人

android

android_alertdialog

问题状态

如何使用单选复选框android在AlertDialog中选择条目？

与内容相关的链接

5 个回复

发起人

android

android_alertdialog

问题状态