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

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。

带有编辑文本的警报对话框

AlertDialog.Builder builder = new AlertDialog.Builder(context);//Context is activity context
final EditText input = new EditText(context);
builder.setTitle(getString(R.string.remove_item_dialog_title));
        builder.setMessage(getString(R.string.dialog_message_remove_item));
 builder.setTitle(getString(R.string.update_qty));
            builder.setMessage("");
            LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
                    LinearLayout.LayoutParams.MATCH_PARENT,
                    LinearLayout.LayoutParams.MATCH_PARENT);
            input.setLayoutParams(lp);
            input.setHint(getString(R.string.enter_qty));
            input.setTextColor(ContextCompat.getColor(context, R.color.textColor));
            input.setInputType(InputType.TYPE_CLASS_NUMBER);
            input.setText("String in edit text you want");
            builder.setView(input);
   builder.setPositiveButton(getString(android.R.string.ok),
                (dialog, which) -> {

//Positive button click event
  });

 builder.setNegativeButton(getString(android.R.string.cancel),
                (dialog, which) -> {
//Negative button click event
                });
        AlertDialog dialog = builder.create();
        dialog.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();

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/

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();
}