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

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();

其他回答

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();

        }

你可以试试这个....

    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();

欲了解更多信息,请查看此链接…

你也可以尝试这种方式,它将为你提供材料样式的对话框

private void showDialog()
{
    String text2 = "<font color=#212121>Medi Notification</font>";//for custom title color

    AlertDialog.Builder builder = new AlertDialog.Builder(this, R.style.AppCompatAlertDialogStyle);
    builder.setTitle(Html.fromHtml(text2));

    String text3 = "<font color=#A4A4A4>You can complete your profile now or start using the app and come back later</font>";//for custom message
    builder.setMessage(Html.fromHtml(text3));

    builder.setPositiveButton("DELETE", new DialogInterface.OnClickListener()
    {
        @Override
        public void onClick(DialogInterface dialog, int which)
        {
            toast = Toast.makeText(getApplicationContext(), "DELETE", Toast.LENGTH_SHORT);
            toast.setGravity(Gravity.CENTER, 0, 0);
            toast.show();              
        }
    });

    builder.setNegativeButton("CANCEL", new DialogInterface.OnClickListener()
    {
        @Override
        public void onClick(DialogInterface dialog, int which)
        {
            toast = Toast.makeText(getApplicationContext(), "CANCEL", Toast.LENGTH_SHORT);
            toast.setGravity(Gravity.CENTER, 0, 0);
            toast.show();
        }
    });
    builder.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();

现在与Jetpack撰写引入android,你可以简单地创建警报对话框使用下面的代码

if (viewModel.shouldDialogOpen.value) {

        AlertDialog(onDismissRequest = { viewModel.shouldDialogOpen.value = false },
            title = { Text("Delete Entry?") },
            text = {
                Text("Are you sure you want to delete this entry?")
            },
            dismissButton = {
                Button(modifier = Modifier.fillMaxWidth(), onClick = {
                    viewModel.shouldDialogOpen.value = false
                }) {
                    Text(text = "Cancel")
                }
            }, confirmButton = {
                Button(modifier = Modifier.fillMaxWidth(), onClick = {
                    viewModel.shouldDialogOpen.value = false
                    viewModel.beginDelete(recipe)
                }) {
                    Text(text = "Okay")
                }
            })
    }

在viewModel中。shouldDialogOpen, shouldDialogOpen是viewmodel中的一个mutablestate字段,当我们需要显示或解散对话框时,我们会改变它的值。

更多的代码样本Jetpack撰写:- https://androidlearnersite.wordpress.com/2021/08/03/jetpack-compose-1-0-0-sample-codes/