我想显示一个对话框/弹出窗口,向用户显示一条消息“您确定要删除此条目吗?”,其中一个按钮说“删除”。当点击Delete时,它应该删除该条目,否则什么都不删除。

我已经为这些按钮写了一个点击监听器,但我如何调用对话框或弹出窗口及其功能?


当前回答

这是一个创建Alert对话框的基本示例:

AlertDialog.Builder dialog = new AlertDialog.Builder(MainActivity.this);
dialog.setCancelable(false);
dialog.setTitle("Dialog on Android");
dialog.setMessage("Are you sure you want to delete this entry?" );
dialog.setPositiveButton("Delete", new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int id) {
        //Action for "Delete".
    }
})
        .setNegativeButton("Cancel ", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
            //Action for "Cancel".
            }
        });

final AlertDialog alert = dialog.create();
alert.show();

其他回答

您可以为此使用AlertDialog,并使用它的Builder类构造一个AlertDialog。下面的例子使用默认的构造函数,它只接受Context,因为对话框将从传入的Context继承适当的主题,但是如果你想这样做,还有一个构造函数允许你指定一个特定的主题资源作为第二个参数。

new AlertDialog.Builder(context)
    .setTitle("Delete entry")
    .setMessage("Are you sure you want to delete this entry?")

    // Specifying a listener allows you to take an action before dismissing the dialog.
    // The dialog is automatically dismissed when a dialog button is clicked.
    .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) { 
            // Continue with delete operation
        }
     })

    // A null listener allows the button to dismiss the dialog and take no further action.
    .setNegativeButton(android.R.string.no, null)
    .setIcon(android.R.drawable.ic_dialog_alert)
    .show();

试试这段代码

AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(MainActivity.this);

    // set title
    alertDialogBuilder.setTitle("AlertDialog Title");

    // set dialog message
    alertDialogBuilder
            .setMessage("Some Alert Dialog message.")
            .setCancelable(false)
            .setPositiveButton("OK", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                            Toast.makeText(this, "OK button click ", Toast.LENGTH_SHORT).show();

                }
            })
            .setNegativeButton("CANCEL",new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                           Toast.makeText(this, "CANCEL button click ", Toast.LENGTH_SHORT).show();

                    dialog.cancel();
                }
            });

    // create alert dialog
    AlertDialog alertDialog = alertDialogBuilder.create();

    // show it
    alertDialog.show();

试试下面的代码:

AlertDialog.Builder builder1 = new AlertDialog.Builder(context);
builder1.setMessage("Write your message here.");
builder1.setCancelable(true);

builder1.setPositiveButton(
    "Yes",
    new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int id) {
            dialog.cancel();
        }
    });

builder1.setNegativeButton(
    "No",
    new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int id) {
            dialog.cancel();
        }
    });

AlertDialog alert11 = builder1.create();
alert11.show();
    LayoutInflater inflater = LayoutInflater.from(HistoryActivity.this);
    final View vv = inflater.inflate(R.layout.dialog_processing_tts, null);
    final AlertDialog.Builder alert = new AlertDialog.Builder(
            HistoryActivity.this);
    alert.setTitle("Delete");
    alert.setView(vv);
    alert.setCancelable(false)
            .setPositiveButton("Delete", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    databaseHelperClass.deleteHistory(list.get(position).getID());
                    list.clear();
                    setAdapterForList();

                }
            })
            .setNegativeButton("Cancel",
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int id) {
                            dialog.cancel();
                        }
                    });

    final AlertDialog dialog = alert.create();
    dialog.show();

我在onClick方法中使用这个AlertDialog:

button.setOnClickListener(v -> {
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    LayoutInflater layoutInflaterAndroid = LayoutInflater.from(this);
    View view = layoutInflaterAndroid.inflate(R.layout.cancel_dialog, null);
    builder.setView(view);
    builder.setCancelable(false);
    final AlertDialog alertDialog = builder.create();
    alertDialog.show();

    view.findViewById(R.id.yesButton).setOnClickListener(v -> onBackPressed());
    view.findViewById(R.id.nobutton).setOnClickListener(v -> alertDialog.dismiss());
});

dialog.xml

<androidx.constraintlayout.widget.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:orientation="vertical">

<TextView
    android:id="@+id/textmain"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_margin="5dp"
    android:gravity="center"
    android:padding="5dp"
    android:text="@string/warning"
    android:textColor="@android:color/black"
    android:textSize="18sp"
    android:textStyle="bold"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent" />


<TextView
    android:id="@+id/textpart2"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_margin="5dp"
    android:gravity="center"
    android:lines="2"
    android:maxLines="2"
    android:padding="5dp"
    android:singleLine="false"
    android:text="@string/dialog_cancel"
    android:textAlignment="center"
    android:textColor="@android:color/black"
    android:textSize="15sp"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/textmain" />


<TextView
    android:id="@+id/yesButton"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginStart="40dp"
    android:layout_marginTop="5dp"
    android:layout_marginEnd="40dp"
    android:layout_marginBottom="5dp"
    android:background="#87cefa"
    android:gravity="center"
    android:padding="10dp"
    android:text="@string/yes"
    android:textAlignment="center"
    android:textColor="@android:color/black"
    android:textSize="15sp"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/textpart2" />


<TextView
    android:id="@+id/nobutton"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginStart="40dp"
    android:layout_marginTop="5dp"
    android:layout_marginEnd="40dp"
    android:background="#87cefa"
    android:gravity="center"
    android:padding="10dp"
    android:text="@string/no"
    android:textAlignment="center"
    android:textColor="@android:color/black"
    android:textSize="15sp"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/yesButton" />


<TextView
    android:layout_width="match_parent"
    android:layout_height="20dp"
    android:layout_margin="5dp"
    android:padding="10dp"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/nobutton" />
</androidx.constraintlayout.widget.ConstraintLayout>