Android上的自定义对话框：如何将标题居中？

我正在开发一个Android应用程序。

如何将正在使用的自定义对话框的标题居中？

只是在试图弄清楚如何做相同的事情的同时找到了这篇文章。这是我为将来会发现此问题的其他人所做的方法。

样式xml如下：

    <?xml version="1.0" encoding="utf-8"?>
    <resources>
        <style name="PauseDialog" parent="@android:style/Theme.Dialog">
            <item name="android:windowTitleStyle">@style/PauseDialogTitle</item>
        </style>

        <style name="PauseDialogTitle" parent="@android:style/TextAppearance.DialogWindowTitle">
            <item name="android:gravity">center_horizontal</item>
        </style>
        <style name="DialogWindowTitle">
        <item name="android:maxLines">1</item>
        <item name="android:scrollHorizontally">true</item>
        <item name="android:textAppearance">@android:style/TextAppearance.DialogWindowTitle</item>
        </style>
    </resources>

And in my activities onCreateDialog method for the dialog I want styled I create the dialog like this:

Dialog pauseDialog = new Dialog(this, R.style.PauseDialog);
pauseDialog.setTitle(R.string.pause_menu_label);
pauseDialog.setContentView(R.layout.pause_menu);

Another way that this can be done programatically is using the setCustomTitle():

// Creating the AlertDialog with a custom xml layout (you can still use the default Android version)
AlertDialog.Builder builder = new AlertDialog.Builder(this);
LayoutInflater inflater = (LayoutInflater)this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view = inflater.inflate(R.layout.viewname, null);
builder.setView(view);

TextView title = new TextView(this);
// You Can Customise your Title here 
title.setText("Custom Centered Title");
title.setBackgroundColor(Color.DKGRAY);
title.setPadding(10, 10, 10, 10);
title.setGravity(Gravity.CENTER);
title.setTextColor(Color.WHITE);
title.setTextSize(20);

builder.setCustomTitle(title);

You can do it in code as well. Assume you have dialog fragment then add following lines of code.

@Override
public void onStart()
{
    super.onStart();

    TextView textView = (TextView) this.getDialog().findViewById(android.R.id.title);
    if(textView != null)
    {
        textView.setGravity(Gravity.CENTER);
    }
}

For your custom DialogFragment you can do this:

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    final Dialog dialog = super.onCreateDialog(savedInstanceState);
    final TextView textView = (TextView) dialog.findViewById(android.R.id.title);
    if(textView != null) {
        textView.setTextAlignment(View.TEXT_ALIGNMENT_CENTER);
    }
    return dialog;
}

You can do it programmatically without custom view:

@Override
public void onStart()
{
    super.onStart();

    TextView textViewVanilla = (TextView) this.getDialog().findViewById(android.R.id.title);
    if(textViewVanilla != null)
    {
        textViewVanilla.setGravity(Gravity.CENTER);
    }
    // support for appcompat v7
    TextView textViewAppcompat = (TextView) this.getDialog().findViewById(android.support.v7.appcompat.R.id.alertTitle);
    if(textViewAppcompat != null)
    {
        textViewAppcompat.setGravity(Gravity.CENTER);
    }
}

Thanks @hesam for the idea. For appcompat layout see Android/sdk/platforms/android-26/data/res/layout/alert_dialog_title_material.xml

Similar to @LandL Partners solution, but in Kotlin:

val builder = AlertDialog.Builder(this)
val inflater = this.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater

val view = inflater.inflate(R.layout.viewname, null)
builder.setView(view)
val title = TextView(this)
title.setText("Custom Centered Title")
title.setBackgroundColor(Color.DKGRAY)
title.setPadding(10, 10, 10, 10)
title.setGravity(Gravity.CENTER)
title.setTextColor(Color.WHITE)
title.setTextSize(20)

builder.setCustomTitle(title)

If you don't call AlertDialog.Builder.setIcon() and AlertDialog.Builder.setTitle(), then your custom dialog will not show the built-in/default title View. In this case you are able to add your custom title View:

AlertDialog.Builder.setView(View view)

As soon as it is you who create this View it is possible to implement any type of alignment.

TextView titleView = (TextView) dialog.findViewById(android.R.id.title);
if(titleView != null) {
titleView.setGravity(Gravity.CENTER);
}

See this KodeCenter article on Android Dialog and AlertDialog for more details.

You've got some starting tips here for modifying the title of a dialog: Android - change custom title view at run time Don't know if it can be centered(haven't tried), but if it's a custom View I guess it's very possible.

Here's a nasty solution.... Extend AlertDialog.Builder and override all the methods (eg. setText, setTitle, setView, etc) to not set the actual Dialog's text/title/view, but to create a new view within the Dialog's View do everything in there. Then you are free to style everything as you please.

To clarify, as far as the parent class is concerned, the View is set, and nothing else.

As far as your custom extended class is concerned, everything is done within that view.

Try this:

TextView titleText = (TextView) helpDialog.findViewById(R.id.alertTitle);
if(titleText != null) {
    titleText.setGravity(Gravity.CENTER);
}

Full code (using android.support.v7.app.AlertDialog):

 AlertDialog.Builder helpDialogBuilder = new AlertDialog.Builder(context)
        .setTitle(/*your title*/)
        .setMessage(/*your message*/)
        .setNegativeButton("Cancel",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int whichButton) {
                        /*you can do something here*/

                        dialog.dismiss();
                    }
                })
        .setPositiveButton("OK",
                new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        /*you can do something here*/

                        dialog.dismiss();
                    }
                });

final AlertDialog helpDialog = helpDialogBuilder.create();

helpDialog.setOnShowListener(new DialogInterface.OnShowListener() {
    @Override
    public void onShow(DialogInterface dialog) {

        TextView titleText = (TextView) helpDialog.findViewById(R.id.alertTitle);
        if(titleText != null) {
            titleText.setGravity(Gravity.CENTER);
        }

        TextView messageText = (TextView) helpDialog.findViewById(android.R.id.message);
        if(messageText != null) {
            messageText.setGravity(Gravity.CENTER);
        }
    }
});

helpDialog.show(); 

    AlertDialog alertDialog = new AlertDialog.Builder(activity)

            .setMessage(message)
            .create();
    alertDialog.setIcon(R.mipmap.ic_launcher_round);

    @SuppressLint("RestrictedApi")
    DialogTitle titleView=new DialogTitle(activity);
    titleView.setText(title);
    titleView.setPaddingRelative(32,32,32,0);
    alertDialog.setCustomTitle(titleView);

In Kotlin, you can do it in 1 line

dialog!!.window!!.attributes = dialog!!.window!!.attributes.apply { dimAmount = 0F }