java - 禁用 AlertDialog 上的保存按钮，除非输入字段不为空

Question

我们需要这个来禁止用户输入空值作为文件名。除非 userInput 不为空，否则应禁用保存按钮。

这是当前代码:

public void openDialog() {
    @SuppressLint("InflateParams") View view = (LayoutInflater.from(AudioRecorder.this)).inflate(R.layout.audio_name_input, null);

    AlertDialog.Builder alertBuilder = new AlertDialog.Builder(AudioRecorder.this);
    alertBuilder.setView(view);
    final EditText userInput = view.findViewById(R.id.userInput);

    alertBuilder.setCancelable(true);
    alertBuilder.setPositiveButton("Save", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            inputName = String.valueOf(userInput.getText());
            Toast.makeText(AudioRecorder.this, "Next audio clip will be named... " + inputName, Toast.LENGTH_SHORT).show();
            filePathMaking();
        }
    });
    alertBuilder.setNegativeButton("cancel", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialogInterface, int i) {
        }
    });

    Dialog dialog = alertBuilder.create();
    dialog.show();
}

Answer 1

你可以这样做:

if(input != null){
    button.setEnabled(true); //you can  click your button now
}else{
    button.setEnabled(false); //you can not click your button
}

<小时/>

根据您的评论进行编辑:

以下是通用自定义对话框的示例:

这将是您的对话框类(或类似的东西，这只是一个示例):

public class FullSizeImageDialog extends Dialog {
private ImageView imageView;
private ProgressBar fullImageProgreesBar;
private Context dialogContext;

public FullSizeImageDialog(@NonNull Context context) {
    super(context);
    setContentView(R.layout.full_size_image_dialog);
    dialogContext = context;
    imageView = findViewById(R.id.full_size_image);
    fullImageProgreesBar = findViewById(R.id.fullImageProgreesBar);
    }
}

这是对话框的布局(在我的例子中是R.id.full_size_image):

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:app="http://schemas.android.com/apk/res-auto"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
   android:background="#66F9B639">


 <!--Place your views here-->


 </android.support.constraint.ConstraintLayout>

当您想显示对话框时，这非常简单:

FullSizeImageDialog dialog = new FullSizeImageDialog ();
dialog.show();

现在，您可以将逻辑放入自定义对话框类中。