android - Android DialogFragment vs Dialog

Question

谷歌建议我们使用简单的 by usingDialogFragment代替简单Dialog的 by using Fragments API，但是DialogFragment对于简单的 Yes-No 确认消息框使用隔离是很荒谬的。在这种情况下，最佳做法是什么？

Answer 1

是的，使用DialogFragment并且onCreateDialog无论如何您都可以简单地使用 AlertDialog 构建器来创建一个简单AlertDialog的带有是/否确认按钮。根本没有太多代码。

关于处理片段中的事件，有多种方法可以做到这一点，但我只是Handler在 my 中定义一条消息Fragment，通过它DialogFragment的构造函数将它传递给它，然后将消息传递回我的片段的处理程序，作为对各种点击事件的适当处理。再次以各种方式做到这一点，但以下对我有用。

在对话框中保存一条消息并在构造函数中实例化它：

private Message okMessage;
...
okMessage = handler.obtainMessage(MY_MSG_WHAT, MY_MSG_OK);

在您的对话框中实现onClickListener，然后根据需要调用处理程序：

public void onClick(.....
    if (which == DialogInterface.BUTTON_POSITIVE) {
        final Message toSend = Message.obtain(okMessage);
        toSend.sendToTarget();
    }
 }

编辑

并且Message可以打包，您可以将其保存onSaveInstanceState并恢复

outState.putParcelable("okMessage", okMessage);

然后在onCreate

if (savedInstanceState != null) {
    okMessage = savedInstanceState.getParcelable("okMessage");
}

Answer 2

您可以创建通用 DialogFragment 子类，如 YesNoDialog 和 OkDialog，如果您在应用程序中大量使用对话框，则传入标题和消息。

public class YesNoDialog extends DialogFragment
{
    public static final String ARG_TITLE = "YesNoDialog.Title";
    public static final String ARG_MESSAGE = "YesNoDialog.Message";

    public YesNoDialog()
    {

    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState)
    {
        Bundle args = getArguments();
        String title = args.getString(ARG_TITLE);
        String message = args.getString(ARG_MESSAGE);

        return new AlertDialog.Builder(getActivity())
            .setTitle(title)
            .setMessage(message)
            .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener()
            {
                @Override
                public void onClick(DialogInterface dialog, int which)
                {
                    getTargetFragment().onActivityResult(getTargetRequestCode(), Activity.RESULT_OK, null);
                }
            })
            .setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener()
            {
                @Override
                public void onClick(DialogInterface dialog, int which)
                {
                    getTargetFragment().onActivityResult(getTargetRequestCode(), Activity.RESULT_CANCELED, null);
                }
            })
            .create();
    }
}

然后使用以下命令调用它：

    DialogFragment dialog = new YesNoDialog();
    Bundle args = new Bundle();
    args.putString(YesNoDialog.ARG_TITLE, title);
    args.putString(YesNoDialog.ARG_MESSAGE, message);
    dialog.setArguments(args);
    dialog.setTargetFragment(this, YES_NO_CALL);
    dialog.show(getFragmentManager(), "tag");

并将结果处理在onActivityResult.

Answer 3

在 AlertDialog 上使用 DialogFragment：

---

• 自 API 级别 13 引入以来：

  Activity 中的showDialog方法已弃用。不建议在代码的其他地方调用对话框，因为您必须自己管理对话框（例如方向更改）。

• 差异 DialogFragment - AlertDialog

  他们有那么大的不同吗？来自有关DialogFragment的 Android 参考：

  DialogFragment 是一个显示对话窗口的片段，浮动在其活动窗口的顶部。该片段包含一个 Dialog 对象，它会根据片段的状态适当地显示该对象。对话框的控制（决定何时显示、隐藏、关闭它）应该通过这里的 API 来完成，而不是直接调用对话框。

• 其他注意事项

  • 由于具有不同屏幕尺寸的设备的多样性，片段是 Android 框架中的自然演变。
  • DialogFragments 和 Fragments 在支持库中可用，这使得该类可用于所有当前使用的 Android 版本。

Answer 4

我建议使用DialogFragment.

当然，考虑到它应该是相当简单的任务，使用它创建一个“是/否”对话框非常复杂，但是创建一个类似的对话框Dialog也非常复杂。

（活动生命周期使它变得复杂 - 你必须让Activity管理对话框的生命周期 -Activity.showDialog如果使用低于 8 的 API 级别，则无法传递自定义参数，例如自定义消息）

好消息是你通常可以DialogFragment很容易地在上面构建自己的抽象。

Answer 5

具有生成器模式的通用 AlertDialogFragment

在我的项目中，我已经使用AlertDialog.Builder了很多，然后才发现它有问题。但是，我不想在我的应用程序的任何地方更改那么多代码。此外，我实际上喜欢OnClickListeners在需要它们的地方（即在使用 等时）将它们作为匿名类setPositiveButton()传递，setNegativeButton()而不必实现数千个回调方法来在对话框片段和持有者片段之间进行通信，这可以在我认为，导致非常混乱和复杂的代码。特别是，如果您在一个片段中有多个不同的对话框，然后需要在回调实现中区分当前显示的是哪个对话框。

因此，我结合了不同的方法来创建一个通用的AlertDialogFragment帮助类，它可以完全像这样 AlertDialog使用：

---

解决方案

（请注意，我在代码中使用了 Java 8 lambda 表达式，因此如果您尚未使用lambda 表达式，您可能需要更改部分代码。）

/**
 * Helper class for dialog fragments to show a {@link AlertDialog}. It can be used almost exactly
 * like a {@link AlertDialog.Builder}
 * <p />
 * Creation Date: 22.03.16
 *
 * @author felix, http://flx-apps.com/
 */
public class AlertDialogFragment extends DialogFragment {
    protected FragmentActivity activity;
    protected Bundle args;
    protected String tag = AlertDialogFragment.class.getSimpleName();

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        activity = getActivity();
        args = getArguments();
    }

    @NonNull
    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        Dialog dialog = setDialogDefaults(new AlertDialog.Builder(getActivity())).create();

        if (args.containsKey("gravity")) {
            dialog.getWindow().getAttributes().gravity = args.getInt("gravity");
        }

        dialog.setOnShowListener(d -> {
            if (dialog != null && dialog.findViewById((android.R.id.message)) != null) {
                ((TextView) dialog.findViewById(android.R.id.message)).setMovementMethod(LinkMovementMethod.getInstance());
            }
        });
        return dialog;
    }

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        return super.onCreateView(inflater, container, savedInstanceState);
    }

    @Override
    public void onDismiss(DialogInterface dialog) {
        super.onDismiss(dialog);

        if (args.containsKey("onDismissListener")) {
            Parcelable onDismissListener = args.getParcelable("onDismissListener");
            if (onDismissListener != null && onDismissListener instanceof ParcelableOnDismissListener) {
                ((ParcelableOnDismissListener) onDismissListener).onDismiss(this);
            }
        }
    }

    /**
     * Sets default dialog properties by arguments which were set using {@link #builder(FragmentActivity)}
     */
    protected AlertDialog.Builder setDialogDefaults(AlertDialog.Builder builder) {
        args = getArguments();
        activity = getActivity();

        if (args.containsKey("title")) {
            builder.setTitle(args.getCharSequence("title"));
        }

        if (args.containsKey("message")) {
            CharSequence message = args.getCharSequence("message");
            builder.setMessage(message);
        }

        if (args.containsKey("viewId")) {
            builder.setView(getActivity().getLayoutInflater().inflate(args.getInt("viewId"), null));
        }

        if (args.containsKey("positiveButtonText")) {
            builder.setPositiveButton(args.getCharSequence("positiveButtonText"), (dialog, which) -> {
                onButtonClicked("positiveButtonListener", which);
            });
        }

        if (args.containsKey("negativeButtonText")) {
            builder.setNegativeButton(args.getCharSequence("negativeButtonText"), (dialog, which) -> {
                onButtonClicked("negativeButtonListener", which);
            });
        }

        if (args.containsKey("neutralButtonText")) {
            builder.setNeutralButton(args.getCharSequence("neutralButtonText"), (dialog, which) -> {
                onButtonClicked("neutralButtonListener", which);
            });
        }

        if (args.containsKey("items")) {
            builder.setItems(args.getStringArray("items"), (dialog, which) -> {
                onButtonClicked("itemClickListener", which);
            });
        }

        // @formatter:off
        // FIXME this a pretty hacky workaround: we don't want to show the dialog if onClickListener of one of the dialog's button click listener were lost
        //       the problem is, that there is no (known) solution for parceling a OnClickListener in the long term (only for state changes like orientation change,
        //       but not if the Activity was completely lost)
        if (
                (args.getParcelable("positiveButtonListener") != null && !(args.getParcelable("positiveButtonListener") instanceof ParcelableOnClickListener)) ||
                (args.getParcelable("negativeButtonListener") != null && !(args.getParcelable("negativeButtonListener") instanceof ParcelableOnClickListener)) ||
                (args.getParcelable("neutralButtonListener") != null && !(args.getParcelable("neutralButtonListener") instanceof ParcelableOnClickListener)) ||
                (args.getParcelable("itemClickListener") != null && !(args.getParcelable("itemClickListener") instanceof ParcelableOnClickListener))
        ) {
            new DebugMessage("Forgot onClickListener. Needs to be dismissed.")
                    .logLevel(DebugMessage.LogLevel.VERBOSE)
                    .show();
            try {
                dismissAllowingStateLoss();
            } catch (NullPointerException | IllegalStateException ignored) {}
        }
        // @formatter:on

        return builder;
    }

    public interface OnDismissListener {
        void onDismiss(AlertDialogFragment dialogFragment);
    }

    public interface OnClickListener {
        void onClick(AlertDialogFragment dialogFragment, int which);
    }

    protected void onButtonClicked(String buttonKey, int which) {
        ParcelableOnClickListener parcelableOnClickListener = getArguments().getParcelable(buttonKey);
        if (parcelableOnClickListener != null) {
            parcelableOnClickListener.onClick(this, which);
        }
    }

    // region Convenience Builder Pattern class almost similar to AlertDialog.Builder
    // =============================================================================================

    public AlertDialogFragment builder(FragmentActivity activity) {
        this.activity = activity;
        this.args = new Bundle();
        return this;
    }

    public AlertDialogFragment addArguments(Bundle bundle) {
        args.putAll(bundle);
        return this;
    }

    public AlertDialogFragment setTitle(int titleStringId) {
        return setTitle(activity.getString(titleStringId));
    }

    public AlertDialogFragment setTitle(CharSequence title) {
        args.putCharSequence("title", title);
        return this;
    }

    public AlertDialogFragment setMessage(int messageStringId) {
        return setMessage(activity.getString(messageStringId));
    }

    public AlertDialogFragment setMessage(CharSequence message) {
        args.putCharSequence("message", message);
        return this;
    }

    public AlertDialogFragment setPositiveButton(int textStringId, OnClickListener onClickListener) {
        return setPositiveButton(activity.getString(textStringId), onClickListener);
    }

    public AlertDialogFragment setPositiveButton(CharSequence text, AlertDialogFragment.OnClickListener onClickListener) {
        args.putCharSequence("positiveButtonText", text);
        args.putParcelable("positiveButtonListener", createParcelableOnClickListener(onClickListener));
        return this;
    }

    public AlertDialogFragment setNegativeButton(int textStringId, AlertDialogFragment.OnClickListener onClickListener) {
        return setNegativeButton(activity.getString(textStringId), onClickListener);
    }

    public AlertDialogFragment setNegativeButton(CharSequence text, AlertDialogFragment.OnClickListener onClickListener) {
        args.putCharSequence("negativeButtonText", text);
        args.putParcelable("negativeButtonListener", createParcelableOnClickListener(onClickListener));
        return this;
    }

    public AlertDialogFragment setNeutralButton(int textStringId, AlertDialogFragment.OnClickListener onClickListener) {
        return setNeutralButton(activity.getString(textStringId), onClickListener);
    }

    public AlertDialogFragment setNeutralButton(CharSequence text, AlertDialogFragment.OnClickListener onClickListener) {
        args.putCharSequence("neutralButtonText", text);
        args.putParcelable("neutralButtonListener", createParcelableOnClickListener(onClickListener));
        return this;
    }

    public AlertDialogFragment setOnDismissListener(OnDismissListener onDismissListener) {
        if (onDismissListener == null) {
            return this;
        }

        Parcelable p = new ParcelableOnDismissListener() {
            @Override
            public void onDismiss(AlertDialogFragment dialogFragment) {
                onDismissListener.onDismiss(dialogFragment);
            }
        };
        args.putParcelable("onDismissListener", p);
        return this;
    }

    public AlertDialogFragment setItems(String[] items, AlertDialogFragment.OnClickListener onClickListener) {
        args.putStringArray("items", items);
        args.putParcelable("itemClickListener", createParcelableOnClickListener(onClickListener));
        return this;
    }

    public AlertDialogFragment setView(int viewId) {
        args.putInt("viewId", viewId);
        return this;
    }

    public AlertDialogFragment setGravity(int gravity) {
        args.putInt("gravity", gravity);
        return this;
    }

    public AlertDialogFragment setTag(String tag) {
        this.tag = tag;
        return this;
    }

    public AlertDialogFragment create() {
        setArguments(args);
        return AlertDialogFragment.this;
    }

    public AlertDialogFragment show() {
        create();
        try {
            super.show(activity.getSupportFragmentManager(), tag);
        }
        catch (IllegalStateException e1) {

            /**
             * this whole part is used in order to attempt to show the dialog if an
             * {@link IllegalStateException} was thrown (it's kinda comparable to
             * {@link FragmentTransaction#commitAllowingStateLoss()} 
             * So you can remove all those dirty hacks if you are sure that you are always
             * properly showing dialogs in the right moments
             */

            new DebugMessage("got IllegalStateException attempting to show dialog. trying to hack around.")
                    .logLevel(DebugMessage.LogLevel.WARN)
                    .exception(e1)
                    .show();

            try {
                Field mShownByMe = DialogFragment.class.getDeclaredField("mShownByMe");
                mShownByMe.setAccessible(true);
                mShownByMe.set(this, true);
                Field mDismissed = DialogFragment.class.getDeclaredField("mDismissed");
                mDismissed.setAccessible(true);
                mDismissed.set(this, false);
            }
            catch (Exception e2) {
                new DebugMessage("error while showing dialog")
                        .exception(e2)
                        .logLevel(DebugMessage.LogLevel.ERROR)
                        .show();
            }
            FragmentTransaction transaction = activity.getSupportFragmentManager().beginTransaction();
            transaction.add(this, tag);
            transaction.commitAllowingStateLoss(); // FIXME hacky and unpredictable workaround
        }
        return AlertDialogFragment.this;
    }

    @Override
    public int show(FragmentTransaction transaction, String tag) {
        throw new NoSuchMethodError("Please use AlertDialogFragment.show()!");
    }

    @Override
    public void show(FragmentManager manager, String tag) {
        throw new NoSuchMethodError("Please use AlertDialogFragment.show()!");
    }

    protected ParcelableOnClickListener createParcelableOnClickListener(AlertDialogFragment.OnClickListener onClickListener) {
        if (onClickListener == null) {
            return null;
        }

        return new ParcelableOnClickListener() {
            @Override
            public void onClick(AlertDialogFragment dialogFragment, int which) {
                onClickListener.onClick(dialogFragment, which);
            }
        };
    }

    /**
     * Parcelable OnClickListener (can be remembered on screen rotation)
     */
    public abstract static class ParcelableOnClickListener extends ResultReceiver implements AlertDialogFragment.OnClickListener {
        public static final Creator<ResultReceiver> CREATOR = ResultReceiver.CREATOR;

        ParcelableOnClickListener() {
            super(null);
        }

        @Override
        public abstract void onClick(AlertDialogFragment dialogFragment, int which);
    }

    /**
     * Parcelable OnDismissListener (can be remembered on screen rotation)
     */
    public abstract static class ParcelableOnDismissListener extends ResultReceiver implements AlertDialogFragment.OnDismissListener {
        public static final Creator<ResultReceiver> CREATOR = ResultReceiver.CREATOR;

        ParcelableOnDismissListener() {
            super(null);
        }

        @Override
        public abstract void onDismiss(AlertDialogFragment dialogFragment);
    }


    // =============================================================================================
    // endregion
}

用法

// showing a normal alert dialog with state loss on configuration changes (like device rotation)
new AlertDialog.Builder(getActivity())
        .setTitle("Are you sure? (1)")
        .setMessage("Do you really want to do this?")
        .setPositiveButton("Yes", (dialog, which) -> Toast.makeText(getContext(), "Yes clicked", Toast.LENGTH_SHORT).show())
        .setNegativeButton("Cancel", null)
        .show();

// showing a dialog fragment using the helper class with no state loss on configuration changes
new AlertDialogFragment.builder(getActivity())
        .setTitle("Are you sure? (2)")
        .setMessage("Do you really want to do this?")
        .setPositiveButton("Yes", (dialog, which) -> Toast.makeText(getContext(), "Yes clicked", Toast.LENGTH_SHORT).show())
        .setNegativeButton("Cancel", null)
        .show();

我在这里发布这个不仅是为了分享我的解决方案，也是因为我想问你们的意见：这种方法在某种程度上是合法的还是有问题的？

Answer 6

我可以建议对@ashishduh 的回答进行一些简化：

public class AlertDialogFragment extends DialogFragment {
public static final String ARG_TITLE = "AlertDialog.Title";
public static final String ARG_MESSAGE = "AlertDialog.Message";

public static void showAlert(String title, String message, Fragment targetFragment) {
    DialogFragment dialog = new AlertDialogFragment();
    Bundle args = new Bundle();
    args.putString(ARG_TITLE, title);
    args.putString(ARG_MESSAGE, message);
    dialog.setArguments(args);
    dialog.setTargetFragment(targetFragment, 0);
    dialog.show(targetFragment.getFragmentManager(), "tag");
}

public AlertDialogFragment() {}

@NonNull
@Override
public AlertDialog onCreateDialog(Bundle savedInstanceState)
{
    Bundle args = getArguments();
    String title = args.getString(ARG_TITLE, "");
    String message = args.getString(ARG_MESSAGE, "");

    return new AlertDialog.Builder(getActivity())
            .setTitle(title)
            .setMessage(message)
            .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener()
            {
                @Override
                public void onClick(DialogInterface dialog, int which)
                {
                    getTargetFragment().onActivityResult(getTargetRequestCode(), Activity.RESULT_OK, null);
                }
            })
            .create();
}

它消除了（类的）用户熟悉组件内部的需要，并使使用变得非常简单：

AlertDialogFragment.showAlert(title, message, this);

PS 在我的情况下，我需要一个简单的警报对话框，这就是我创建的。您可以将该方法应用于是/否或您需要的任何其他类型。

Answer 7

DialogFragment 基本上是一个可以用作对话框的 Fragment。

由于以下原因，在 Dialog 上使用 DialogFragment：

• DialogFragment 在配置更改和保存和恢复流程后自动重新创建
• DialogFragment 继承了 Fragment 的完整生命周期
• 不再有 IllegalStateExceptions 和泄漏的窗口崩溃。当活动被销毁而警报对话框仍然存在时，这很常见。

更多详情

Answer 8

将 Dialog 用于简单的是或否对话框。

当您需要更复杂的视图时，您需要掌握生命周期，例如 oncreate、请求权限、任何生命周期覆盖，我会使用对话框片段。因此，您将权限和对话框需要操作的任何其他代码分开，而无需与调用活动进行通信。

Answer 9

DialogFragment 具有对话框和片段的强大功能。基本上所有的生命周期事件都可以通过 DialogFragment 自动管理得很好，例如屏幕配置的更改等。

Answer 10

对话框：对话框是提示用户做出决定或输入附加信息的小窗口。

DialogFragment： DialogFragment 是一个特殊的片段子类，设计用于创建和托管对话框。它允许 FragmentManager 管理对话框的状态并在发生配置更改时自动恢复对话框。