Android AlertDialog自定义标题后消息无法居中，始终左对齐求助

Hey there! Let's sort out that AlertDialog message alignment problem you're having. You mentioned you've already set up a custom title, so here are two solid approaches to get your message centered properly:

If you want to stick with the default AlertDialog structure but just center the message, you can grab the system's built-in message TextView and update its gravity after showing the dialog:

// 先构建并显示对话框
String ScoreTitle = getResources().getString(R.string.AlertTitle);
AlertDialog.Builder alrtbuilder = new AlertDialog.Builder(this);
AlertDialog dialog = alrtbuilder.setTitle(ScoreTitle)
        .setMessage("你的对话框消息内容")
        .setPositiveButton("确定", (d, which) -> d.dismiss())
        .create();
dialog.show();

// 获取系统默认的消息TextView并设置居中
TextView messageView = dialog.findViewById(android.R.id.message);
if (messageView != null) {
    messageView.setGravity(Gravity.CENTER);
    // 可选：如果需要左右间距，添加这行
    // messageView.setPadding(32, 16, 32, 16);
}

This works because android.R.id.message is the standard ID the system uses for the AlertDialog's message text view. It's a quick fix without needing a full custom layout.

Since you're already inflating a custom layout (simple_dialog.xml), this is the most reliable way to control every part of the dialog's appearance, including centered text.

First, update your simple_dialog.xml to explicitly set gravity on your message text view:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:padding="16dp">

    <!-- 你的自定义标题 -->
    <TextView
        android:id="@+id/custom_title"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textSize="18sp"
        android:textStyle="bold"
        android:gravity="center" />

    <!-- 居中的消息TextView -->
    <TextView
        android:id="@+id/dialog_message"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:layout_marginTop="16dp"
        android:textSize="16sp" />

    <!-- 可选：添加分隔线或其他自定义元素 -->
</LinearLayout>

Then modify your Java code to populate the custom layout's views:

TextView vehicle_no = findViewById(R.id.vehicle_no);
String ScoreTitle = getResources().getString(R.string.AlertTitle);
AlertDialog.Builder alrtbuilder = new AlertDialog.Builder(this);
Context mContext = alrtbuilder.getContext();
LayoutInflater mLayoutInflater = LayoutInflater.from(mContext);
View mView = mLayoutInflater.inflate(R.layout.simple_dialog, null);

// 设置自定义标题
TextView customTitle = mView.findViewById(R.id.custom_title);
customTitle.setText(ScoreTitle);

// 设置居中的消息内容
TextView dialogMessage = mView.findViewById(R.id.dialog_message);
dialogMessage.setText("你的对话框消息内容");

// 绑定自定义布局到对话框
alrtbuilder.setView(mView);

// 添加按钮逻辑
alrtbuilder.setPositiveButton("确定", (dialog, which) -> dialog.dismiss());
alrtbuilder.setNegativeButton("取消", (dialog, which) -> dialog.dismiss());

// 显示对话框
AlertDialog dialog = alrtbuilder.create();
dialog.show();

This approach gives you full control over spacing, font styles, and alignment—no reliance on system defaults, so it's more consistent across Android versions.

内容的提问来源于stack exchange，提问作者John