Android: AlertDialog 未显示

Question

我希望在 Activity 中按回时显示一个警告对话框（一种从用户那里获取一些输入的表单），例如

@Override
public void onBackPressed() {
    showFormDialog();
}

private void showFormDialog() {
    //Preparing views
    LayoutInflater inflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);

    View layout = inflater.inflate(R.layout.dialog_form, (ViewGroup) findViewById(R.id.llid));
    //layout_root should be the name of the "top-level" layout node in the dialog_layout.xml file.
    final EditText txtFB = (EditText) layout.findViewById(R.id.txtFB);

    //Building dialog
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setView(layout);
    builder.setPositiveButton("Save", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            dialog.dismiss();
            //save info where you want it
        }
    });
    builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            dialog.dismiss();
        }
    });
    AlertDialog dialog = builder.create();
}

dialog_form.xml

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">
    <LinearLayout
        android:id="@+id/llid"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <EditText
            android:id="@+id/txtFB"
            android:layout_width="250dp"
            android:layout_height="200dp"
            android:text="hello type something here"/>
    </LinearLayout> </LinearLayout>

我可以看到 showFormDialog 代码在返回时执行，但没有显示 AlertDialog！

Answer 1

你没来电.show()

dialog.show();

.show() 使用提供给该构建器的参数创建一个 AlertDialog 并立即显示对话框。

Answer 2

只需添加这个

dialog.show();

创建它是不够的。你应该展示它。

Answer 3

添加dialog.show()：

AlertDialog dialog = builder.create();
dialog.show();

Android: AlertDialog 未显示

Android: AlertDialog not showing up

android

android-layout

android-alertdialog