Android 弹出进度条对话框 避免用户点击界面交互

private ProgressDialog progressDialog;

private void showLoading_PD() {
if (progressDialog == null) {
progressDialog = new ProgressDialog(this);   // this = Activity
progressDialog.setMessage("加载中…");
progressDialog.setIndeterminate(true);
progressDialog.setCancelable(false);  // 屏蔽返回键
progressDialog.setCanceledOnTouchOutside(false); // 屏蔽外部点击
}
progressDialog.show();
}

private void dismissLoading_PD() {
if (progressDialog != null && progressDialog.isShowing()) {
progressDialog.dismiss();
}
}

<?xml version="1.0" encoding="utf-8"">
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:padding="24dp"
android:gravity="center_vertical">

<ProgressBar
android:layout_width="32dp"
android:layout_height="32dp"
android:indeterminate="true"/>

<TextView
android:id="@+id/tv_msg"
android:layout_marginStart="16dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="加载中…"
android:textSize="16sp"/>
</LinearLayout>

public class LoadingDialog {

private final Dialog dialog;

public LoadingDialog(@NonNull Activity activity) {
dialog = new Dialog(activity);
dialog.setContentView(R.layout.dialog_loading);
// 去掉标题
if (dialog.getWindow() != null) {
dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
}
// 关键：禁止一切返回/触摸取消
dialog.setCancelable(false);
dialog.setCanceledOnTouchOutside(false);
}

public void show() {
if (!dialog.isShowing()) dialog.show();
}

public void dismiss() {
if (dialog.isShowing()) dialog.dismiss();
}
}

LoadingDialog loading = new LoadingDialog(this);   // this = Activity
loading.show();
// ...耗时操作...
loading.dismiss();