Dialog物件

Dialog物件
Dialog物件分成4種：
    AlertDialog, ProgressDialog, DatePickerDialog, TimePickerDialog
這裡只介紹最基本的AlertDialog
其他使用方式可在官網的Dev Gudie - Framework Topics - User Interface - Creating Dialogs查詢

Adding buttons
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder
        .setMessage("Are you sure you want to exit?")
        .setCancelable(false)
        // 有setPositiveButton, setNegativeButton, setNeutralButton
        .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int id) {
                MyActivity.this.finish();
            }
        })
        .setNegativeButton("No", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int id) {
                dialog.cancel();
            }
        });
    AlertDialog alert = builder.create();

Adding a list
    final CharSequence[] items = {"Red", "Green", "Blue"};
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("Pick a color");
    builder.setItems(items, new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int item) {
            Toast.makeText(getApplicationContext(), items[item], Toast.LENGTH_SHORT).show();
        }
    });
    AlertDialog alert = builder.create();

Adding checkboxes and radio buttons
    final CharSequence[] items = {"Red", "Green", "Blue"};
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("Pick a color");
    builder.setSingleChoiceItems(items, -1, new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int item) {
            Toast.makeText(getApplicationContext(), items[item], Toast.LENGTH_SHORT).show();
        }
    });
    AlertDialog alert = builder.create();