使用SimpleCursorAdapter.ViewBinder更改TextView的颜色

Question

我正在为Android开发一个闹钟应用程序,我希望在主屏幕上显示警报列表.其中的每一行都ListView在xml文件中定义.我希望TextViews每周的每一天都能分开.程序将检查sqlite db是否为例如.mondayis = 1的值,然后将其颜色更改TextView为红色.我写了这段代码,但这不起作用.怎么了？

private void fillData() {

    // Get all of the notes from the database and create the item list
    Cursor c = db.fetchAllAlarms();
    startManagingCursor(c);

    String[] from = new String[] { db.KEY_TIME, db.KEY_NAME };
    int[] to = new int[] { R.id.time, R.id.alarmName };

    // Now create an array adapter and set it to display using our row
    SimpleCursorAdapter alarms =
        new SimpleCursorAdapter(this, R.layout.alarm_row, c, from, to);
        alarms.setViewBinder(new SimpleCursorAdapter.ViewBinder() {
        public boolean setViewValue(View view, Cursor cursor, int columnIndex) {
            int dayOfWeekIndex = cursor.getColumnIndex("mon");
            if (dayOfWeekIndex == columnIndex) {
                int color = cursor.getInt(dayOfWeekIndex);
                switch(color) {
                case 0: ((TextView) view).setTextColor(Color.RED); break;
                case 1: ((TextView) view).setTextColor(Color.GRAY); break;
                }
                return true;
            }
            return false;
        }
    });

Answer 1

从Android文档SimpleCursorAdapter.ViewBinder:

将指定索引定义的Cursor列绑定到指定视图.当此ViewBinder处理绑定时,此方法必须返回true.如果此方法返回false,SimpleCursorAdapter将尝试自行处理绑定.

换句话说,您的实现setViewValue不应该特定于任何一个View,因为它SimpleCursorAdapter会View在填充时对每个实现(根据您的实现)进行更改ListView.setViewValue基本上你有机会根据你的数据做任何你想做的事情Cursor,包括设置你的观点的颜色.尝试这样的事情,

public boolean setViewValue(View view, Cursor cursor, int columnIndex){    
    // if this holds true, then you know that you are currently binding text to
    // the TextView with id "R.id.alarmName"
    if (view.getId() == R.id.alarmName) {
        final int dayOfWeekIndex = cursor.getColumnIndex("day_of_week");
        final int color = cursor.getInt(dayOfWeekIndex);

        switch(color) {
        case 0: ((TextView) view).setTextColor(Color.RED); break;
        case 1: /* ... */ break;
        case 2: /* ... */ break;
        /* etc. */
        }
        return true;
    }
    return false;
}

需要注意的是上面的代码假定一个名为列"day_of_week"其持有int价值0-6(指定一周的某一天).