0%

Android 显示一个单选列表对话框(还可利用二维数组配对数据)

显示一个单选列表对话框

一、先丢代码,方便“面向搜索引擎编程”的同志们

  1. 不考虑 itemvalue 的配对的情况下(很简单的啦):
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    new AlertDialog.Builder(context)
    .setTitle(R.string.title)
    .setSingleChoiceItems(
    R.array.items, // 显示的每行的内容
    checkedItem, // 已选中的项( -1 均不选中)
    (dialog, which) -> {
    checkedItem = which; // 保存选中的项的在 R.array.items 中所处的位置(从 0 开始)
    dialog.dismiss();
    }
    )
    .setNegativeButton(android.R.string.cancel, null) // “取消”按钮
    .show();
  2. itemvalue 配对的情况下(实现中利用了一个二维数组,或许还有更好的方案):
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    // 此例中 Items 和 Values 的内容是按顺序一一对应的
    String[][] keyValuePair = {
    getResources().getStringArray(R.array.items), // Items
    getResources().getStringArray(R.array.values) // Values
    };

    new AlertDialog.Builder(context)
    .setTitle(R.string.title)
    .setSingleChoiceItems(
    keyValuePair[0], // 显示的每行的内容
    checkedKeyValuePairPosition, // 已选中的项的位置( -1 均不选中)
    (dialog, which) -> {
    checkedKeyValuePairPosition = which; // 保存选中的项所处的位置(从 0 开始)
    checkedKeyValuePairValue =
    keyValuePair[1][which]; // 保存选中的项对应的 Value
    dialog.dismiss();
    }
    )
    .setNegativeButton(R.string.cancel, null) // “取消”按钮
    .show();

二、builder 里提供的 setSingleChoiceItems 目前看是有四种,可以按需使用。上方的代码只用了其中一种,使用方式区别不大,靠官方文档的注释应该就足够了。这里略微带过几小段:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
/**
* Set a list of items to be displayed in the dialog as the content, you will be notified of
* the selected item via the supplied listener. This should be an array type i.e.
* R.array.foo The list will have a check mark displayed to the right of the text for the
* checked item. Clicking on an item in the list will not dismiss the dialog. Clicking on a
* button will dismiss the dialog.
*
* @param itemsId the resource id of an array i.e. R.array.foo
* @param checkedItem specifies which item is checked. If -1 no items are checked.
* @param listener notified when an item on the list is clicked. The dialog will not be
* dismissed when an item is clicked. It will only be dismissed if clicked on a
* button, if no buttons are supplied it's up to the user to dismiss the dialog.
*
* @return This Builder object to allow for chaining of calls to set methods
*/
public Builder setSingleChoiceItems(@ArrayRes int itemsId, int checkedItem,
final OnClickListener listener)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
/**
* Set a list of items to be displayed in the dialog as the content, you will be notified of
* the selected item via the supplied listener. The list will have a check mark displayed to
* the right of the text for the checked item. Clicking on an item in the list will not
* dismiss the dialog. Clicking on a button will dismiss the dialog.
*
* @param cursor the cursor to retrieve the items from.
* @param checkedItem specifies which item is checked. If -1 no items are checked.
* @param labelColumn The column name on the cursor containing the string to display in the
* label.
* @param listener notified when an item on the list is clicked. The dialog will not be
* dismissed when an item is clicked. It will only be dismissed if clicked on a
* button, if no buttons are supplied it's up to the user to dismiss the dialog.
*
* @return This Builder object to allow for chaining of calls to set methods
*/
public Builder setSingleChoiceItems(Cursor cursor, int checkedItem, String labelColumn,
final OnClickListener listener)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
/**
* Set a list of items to be displayed in the dialog as the content, you will be notified of
* the selected item via the supplied listener. The list will have a check mark displayed to
* the right of the text for the checked item. Clicking on an item in the list will not
* dismiss the dialog. Clicking on a button will dismiss the dialog.
*
* @param items the items to be displayed.
* @param checkedItem specifies which item is checked. If -1 no items are checked.
* @param listener notified when an item on the list is clicked. The dialog will not be
* dismissed when an item is clicked. It will only be dismissed if clicked on a
* button, if no buttons are supplied it's up to the user to dismiss the dialog.
*
* @return This Builder object to allow for chaining of calls to set methods
*/
public Builder setSingleChoiceItems(CharSequence[] items, int checkedItem, final OnClickListener listener)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
/**
* Set a list of items to be displayed in the dialog as the content, you will be notified of
* the selected item via the supplied listener. The list will have a check mark displayed to
* the right of the text for the checked item. Clicking on an item in the list will not
* dismiss the dialog. Clicking on a button will dismiss the dialog.
*
* @param adapter The {@link ListAdapter} to supply the list of items
* @param checkedItem specifies which item is checked. If -1 no items are checked.
* @param listener notified when an item on the list is clicked. The dialog will not be
* dismissed when an item is clicked. It will only be dismissed if clicked on a
* button, if no buttons are supplied it's up to the user to dismiss the dialog.
*
* @return This Builder object to allow for chaining of calls to set methods
*/
public Builder setSingleChoiceItems(ListAdapter adapter, int checkedItem, final OnClickListener listener)

三、更多

如果需要多选的话,setMultiChoiceItems 拿来用就行了。