如何在 Android 上为 Yes/No 重复使用 AlertDialog？

Question

我正在尝试找到重用显示自定义标题的对话框的方法，然后将“是/否”单击发送到已启动该对话框的功能。

我有两个按钮，Save 和 Dismiss，都调用 Yes/No Dialog，一个显示“Do you want to save”，另一个显示“Dismiss changes？”。

我认为我的程序很“脏”但我想它可以工作，但我的问题是“视图视图”变量，我不知道如何将它从 Activity 传递给 Dialog，所以我可以使用它来调用启动对话框的函数。

提前致谢， 赫尼赫德兹

.java 我的活动（片段）

public void open_HH_Fragment_YesNo(View view, String aux_title, String aux_function)
{
    Bundle bundle=new Bundle();
    bundle.putString("setMessage", aux_title);
    bundle.putString("callingFunction", aux_function);

    DialogFragment newFragment = new HH_Fragment_YesNo();
    newFragment.setArguments(bundle);
    newFragment.show(getSupportFragmentManager(), "HH_Fragment_YesNo");
}

public void SaveChanges(View view, String aux_YesNo)
{
    if (aux_YesNo == "")
    {
        Toast.makeText(this, "Save changes?", Toast.LENGTH_SHORT).show();
        open_HH_Fragment_YesNo(view, "Save changes?", "SaveChanges");
    }
    else if (aux_YesNo == "Yes")
    {
        Toast.makeText(this, "Saving changes", Toast.LENGTH_SHORT).show();
    }
    else if (aux_YesNo == "No")
    {
        Toast.makeText(this, "Save Cancelled", Toast.LENGTH_SHORT).show();
    }
}

public void DismissChanges(View view, String aux_YesNo)
{
    if (aux_YesNo == "")
    {
        Toast.makeText(this, "Dismiss changes?", Toast.LENGTH_SHORT).show();
        open_HH_Fragment_YesNo(view, "Dismiss changes?", "DismissChanges");
    }
    else if (aux_YesNo == "Yes")
    {
        Toast.makeText(this, "Dismiss OK", Toast.LENGTH_SHORT).show();
        Close(view);
    }
    else if (aux_YesNo == "No")
    {
        Toast.makeText(this, "Dismiss Cancelled", Toast.LENGTH_SHORT).show();
    }
}

// The dialog fragment receives a reference to this Activity through the
// Fragment.onAttach() callback, which it uses to call the following methods
// defined by the HH_Fragment_YesNo.YesNoDialogListener interface
@Override
public void onDialogPositiveClick(DialogFragment dialog, View view, String aux_function)
{
    // User touched the dialog's positive button
    Toast.makeText(this, "User clicked on Yes", Toast.LENGTH_SHORT).show();

    if (aux_function == "SaveChanges")
    {
        SaveChanges(view, "Yes");
    }
    else if (aux_function == "DismissChanges")
    {
        DismissChanges(view, "Yes");
    }
}

@Override
public void onDialogNegativeClick(DialogFragment dialog, View view, String aux_function)
{
    Toast.makeText(this, "User clicked on NO", Toast.LENGTH_SHORT).show();

    if (aux_function == "SaveChanges")
    {
        SaveChanges(view, "No");
    }
    else if (aux_function == "DismissChanges")
    {
        DismissChanges(view, "No");
    }
}

我的对话框的.java（完整）

public class HH_Fragment_YesNo extends DialogFragment
{
    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState)
    {
    // Use the Builder class for convenient dialog construction
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    String setMessage = getArguments().getString("setMessage");
    final String callingFunction = getArguments().getString("callingFuntion");

    builder
        .setMessage(setMessage)                                             // R.string.dialog_fire_missiles
        .setPositiveButton("Sí", new DialogInterface.OnClickListener()      // R.string.fire
        {
            public void onClick(DialogInterface dialog, int id)
            {
                // Exit without saving
                mListener.onDialogPositiveClick(HH_Fragment_YesNo.this, view, callingFunction);
            }
        })
        .setNegativeButton("No", new DialogInterface.OnClickListener()      // R.string.cancel
        {
            public void onClick(DialogInterface dialog, int id)
            {
                // User cancelled the dialog
                mListener.onDialogNegativeClick(HH_Fragment_YesNo.this, view, callingFunction);
            }
        });

    // Create the AlertDialog object and return it
    return builder.create();
}


/* The activity that creates an instance of this dialog fragment must
 * implement this interface in order to receive event callbacks.
 * Each method passes the DialogFragment in case the host needs to query it. */
public interface YesNoDialogListener
{
    public void onDialogPositiveClick(DialogFragment dialog, View view, String aux_Function);
    public void onDialogNegativeClick(DialogFragment dialog, View view, String aux_Function);
}


// Use this instance of the interface to deliver action events
YesNoDialogListener mListener;


// Override the Fragment.onAttach() method to instantiate the NoticeDialogListener
@Override
public void onAttach(Activity activity)
{
    super.onAttach(activity);
    // Verify that the host activity implements the callback interface
    try
    {
        // Instantiate the NoticeDialogListener so we can send events to the host
        mListener = (YesNoDialogListener) activity;
    }
    catch (ClassCastException e)
    {
        // The activity doesn't implement the interface, throw exception
        throw new ClassCastException(activity.toString() + " must implement NoticeDialogListener");
    }
}
}

Answer 1

完整的解决方案试试这个

1) 创建界面

import android.content.DialogInterface;

public interface AlertMagnatic {

    public abstract void PositiveMethod(DialogInterface dialog, int id);
    public abstract void NegativeMethod(DialogInterface dialog, int id);
}

2) 确认对话框的泛化方法。

public static void getConfirmDialog(Context mContext,String title, String msg, String positiveBtnCaption, String negativeBtnCaption, boolean isCancelable, final AlertMagnatic target) {
        AlertDialog.Builder builder = new AlertDialog.Builder(mContext);

        int imageResource = android.R.drawable.ic_dialog_alert;
        Drawable image = mContext.getResources().getDrawable(imageResource);

        builder.setTitle(title).setMessage(msg).setIcon(image).setCancelable(false).setPositiveButton(positiveBtnCaption, new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int id) {
                target.PositiveMethod(dialog, id);
            }
        }).setNegativeButton(negativeBtnCaption, new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int id) {
                target.NegativeMethod(dialog, id);
            }
        });

        AlertDialog alert = builder.create();
        alert.setCancelable(isCancelable);
        alert.show();
        if (isCancelable) {
            alert.setOnCancelListener(new OnCancelListener() {

                @Override
                public void onCancel(DialogInterface arg0) {
                    target.NegativeMethod(null, 0);
                }
            });
        }
    }

3) 使用方法

getConfirmDialog(getString(R.string.logout), getString(R.string.logout_message), getString(R.string.yes), getString(R.string.no), false,
                new AlertMagnatic() {

                    @Override
                    public void PositiveMethod(final DialogInterface dialog, final int id) {}

                    @Override
                    public void NegativeMethod(DialogInterface dialog, int id) {

                    }
                });

Answer 2

由于此页面是 Google 上的第一个热门页面，而且它似乎是一项如此常见的任务，但很少有人提及它，所以我将分享我发现的展示可重复使用的 DialogFragment 的方式。

如果您想从同一个类中多次重用同一个对话框，但每次都执行不同的操作，那么使用接口会变得非常混乱。此解决方案是解决该问题的一种简单直接的方法，不会带来任何缺点。

编辑 2017-02-25： 此答案之前使用抽象类来实现确认（）和取消（），但是如果您尝试将匿名类用作 DialogFragment，较新版本的 Android 将崩溃并出现以下错误： p>

java.lang.IllegalStateException: Fragment null must be a public static class to be properly recreated from instance state.

所以我修改了使用 Runnables 的解决方案，它在 Java8 中非常好用，但没有它也可行

首先，创建一个实现Dialog本身创建的类：

/**
 * This is a reusable convenience class which makes it easy to show a confirmation dialog as a DialogFragment.
 * Create a new instance, call setArgs(...), setConfirm(), and setCancel() then show it via the fragment manager as usual.
 */
public class ConfirmationDialog extends DialogFragment {
    // Do nothing by default
    private Runnable mConfirm = new Runnable() {
        @Override
        public void run() {
        }
    };
    // Do nothing by default
    private Runnable mCancel = new Runnable() {
        @Override
        public void run() {
        }
    };

    public void setArgs(String message) {
        setArgs("" , message);
    }

    public void setArgs(String title, String message) {
        Bundle args = new Bundle();
        args.putString("message", message);
        args.putString("title", title);
        setArguments(args);
    }

    public void setConfirm(Runnable confirm) {
        mConfirm = confirm;
    }

    public void setCancel(Runnable cancel) {
        mCancel = cancel;
    }

    @Override
    public MaterialDialog onCreateDialog(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Resources res = getActivity().getResources();
        String title = getArguments().getString("title");
        return new MaterialDialog.Builder(getActivity())
                .title(title.equals("") ? res.getString(R.string.app_name) : title)
                .content(getArguments().getString("message"))
                .positiveText(res.getString(R.string.dialog_ok))
                .negativeText(res.getString(R.string.dialog_cancel))
                .callback(new MaterialDialog.ButtonCallback() {
                    @Override
                    public void onPositive(MaterialDialog dialog) {
                        mConfirm.run();
                    }

                    @Override
                    public void onNegative(MaterialDialog dialog) {
                        mCancel.run();
                    }
                })
                .show();
    }
}

其次，您应该在您的Activity 中创建一个通用方法，使用片段管理器显示DialogFragment：

/**
 * Global method to show dialog fragment
 * @param newFragment  the DialogFragment you want to show
 */
public void showDialogFragment(DialogFragment newFragment) {
    // DialogFragment.show() will take care of adding the fragment
    // in a transaction. We also want to remove any currently showing
    // dialog, so make our own transaction and take care of that here.
    FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
    Fragment prev = getSupportFragmentManager().findFragmentByTag("dialog");
    if (prev != null) {
        ft.remove(prev);
    }
    // save transaction to the back stack
    ft.addToBackStack("dialog");
    newFragment.show(ft, "dialog");
}

然后您可以在Activity 中的任何位置显示一个确认对话框，如下所示：

ConfirmationDialog dialog = new ConfirmationDialog ();
dialog.setArgs(stringDialogTitle, stringDialogMessage);
Runnable confirm = new Runnable() {
    @Override
    public void run() {
        doStuff();
    }
};
dialog.setConfirm(confirm);
showDialogFragment(dialog);

如果你有 Java8，你可以对函数使用 lambda，这将使代码不那么冗长。示例见here。