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

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>

其他回答

在过去的几天里,我的同事一直在问我如何在Xamarin中使用AlertDialog。Android和几乎所有人都把这个问题作为参考发给了我,他们在问我之前读了这个问题(没有找到答案),所以这里是Xamarin。Android (c#)版本:

var alertDialog = new AlertDialog.Builder(this) // this: Activity
    .SetTitle("Hello!")
    .SetMessage("Are you sure?")
    .SetPositiveButton("Ok", (sender, e) => { /* ok things */ })
    .SetNegativeButton("Cancel", (sender, e) => { /* cancel things */ })
    .Create();

alertDialog.Show();

// you can customize your AlertDialog, like so
var tvMessage = alertDialog.FindViewById<TextView>(Android.Resource.Id.Message);
tvMessage.TextSize = 13;
// ...
new AlertDialog.Builder(context)
    .setTitle("title")
    .setMessage("message")
    .setPositiveButton(android.R.string.ok, null)
    .show();

在材质组件库中,你可以使用MaterialAlertDialogBuilder

   MaterialAlertDialogBuilder(context)
        .setMessage("Are you sure you want to delete this entry?")
        .setPositiveButton("Delete") { dialog, which ->
            // Respond to positive button press
        }
        .setNegativeButton("Cancel") { dialog, which ->
            // Respond to positive button press
        }   
        .show()

使用Compose 1.0。X你可以使用:

val openDialog = remember { mutableStateOf(true) }

if (openDialog.value) {
    AlertDialog(
        onDismissRequest = {
            // Dismiss the dialog when the user clicks outside the dialog or on the back
            // button. If you want to disable that functionality, simply use an empty
            // onCloseRequest.
            openDialog.value = false
        },
        title = null,
        text = {
            Text(
                "Are you sure you want to delete this entry?"
            )
        },
        confirmButton = {
            TextButton(
                onClick = {
                    openDialog.value = false
                }
            ) {
                Text("Delete")
            }
        },
        dismissButton = {
            TextButton(
                onClick = {
                    openDialog.value = false
                }
            ) {
                Text("Cancel")
            }
        }
    )
}

只是当你想解散对话框时要小心——使用dialog.dismiss()。在我的第一次尝试中,我使用了遣散dialog(0)(我可能从某个地方复制),有时它可以工作。使用系统提供的对象听起来是更安全的选择。

现在最好使用DialogFragment而不是直接创建AlertDialog。

怎么做?参见:https://stackoverflow.com/a/21032871/1390874 为什么?参见:https://stackoverflow.com/a/13765411/1390874