Spinner

先Adapter，后setSelection()。

使用

1. xml布局，以dialog形式，弹出对话框选择

        <Spinner
            android:id="@+id/spinner
            android:layout_width="match_parent"
            android:layout_height="wrap_conten"
            android:background="@null"
            android:gravity="right"
            android:spinnerMode="dialog" />

2. res / layout / spinner_item.xml

<?xml version="1.0" encoding="utf-8"?>
<CheckedTextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/checkedTextViewCustom"
    style="?android:attr/spinnerDropDownItemStyle"
    android:layout_width="match_parent"
    android:layout_height="40dp"
    android:ellipsize="marquee"
    android:singleLine="true"
    android:textAlignment="inherit"
    android:textSize="10sp" />

3. activity

		List<String> xxx = new ArrayList<>();
		xxx.add("选项A");
		xxx.add("选项B");
		xxx.add("选项C");
		...
		ArrayAdapter<String> adapter = new ArrayAdapter<>(this, R.layout.spinner_item, xxx);
        state.setAdapter(adapter);
        state.setSelection(int n); //开局选一个，或者不写，默认第一行
        state.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
     
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
     
                ...
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {
     
				...
            }
        });