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

使用Anko (Kotlin开发人员的官方库),您可以简单地使用

alert("Alert title").show()

或者更复杂的:

alert("Hi, I'm Roy", "Have you tried turning it off and on again?") {
    yesButton { toast("Oh…") }
    noButton {}
}.show()

导入Anko:

implementation "org.jetbrains.anko:anko:0.10.8"

其他回答

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();

使用Anko (Kotlin开发人员的官方库),您可以简单地使用

alert("Alert title").show()

或者更复杂的:

alert("Hi, I'm Roy", "Have you tried turning it off and on again?") {
    yesButton { toast("Oh…") }
    noButton {}
}.show()

导入Anko:

implementation "org.jetbrains.anko:anko:0.10.8"

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>

创建这个静态方法,并在任何需要的地方使用它。

public static void showAlertDialog(Context context, String title, String message, String posBtnMsg, String negBtnMsg) {
            AlertDialog.Builder builder = new AlertDialog.Builder(context);
            builder.setTitle(title);
            builder.setMessage(message);
            builder.setPositiveButton(posBtnMsg, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    dialog.cancel();
                }
            });
            builder.setNegativeButton(negBtnMsg, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    dialog.cancel();
                }
            });
            AlertDialog dialog = builder.create();
            dialog.show();

        }
public void showSimpleDialog(View view) {
    // Use the Builder class for convenient dialog construction
    AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
    builder.setCancelable(false);
    builder.setTitle("AlertDialog Title");
    builder.setMessage("Simple Dialog Message");
    builder.setPositiveButton("OK!!!", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int id) {
            //
        }
    })
    .setNegativeButton("Cancel ", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {

        }
    });

    // Create the AlertDialog object and return it
    builder.create().show();
}

也可以看看我的关于Android对话的博客,你会在这里找到所有的细节:http://www.fahmapps.com/2016/09/26/dialogs-in-android-part1/。