【发布时间】:2015-11-20 03:07:00
【问题描述】:
想法就在这里,但它不工作,很想把它做好,我完全是个初学者)
String temperature = editText5.getText().toString();
String percent = editText7.getText().toString();
Cursor c1 = db.query("mytable", null, "temperature, percent = ?", new String[]{temperature, percent}, null, null, null);
if (c1.moveToFirst()) {
int ckoef = c1.getColumnIndex("ckoef");
int density = c1.getColumnIndex("density");
do {
textView9.setText(c1.getString(ckoef));
textView11.setText(c1.getString(density));
} while (c1.moveToNext());
} else
c1.close();
表格是这样的
ID = 1, temperature = 0, percent = 10, ckoef = 4.025, density = 1012.5
ID = 2, temperature = 10, percent = 10, ckoef = 4.034, density = 1012.5
ID = 3, temperature = 20, percent = 10, ckoef = 4.043, density = 1012.5
ID = 4, temperature = 30, percent = 10, ckoef = 4.057, density = 1012.5
ID = 5, temperature = 40, percent = 10, ckoef = 4.075, density = 1012.5
ID = 6, temperature = 50, percent = 10, ckoef = 4.085, density = 1012.5
ID = 7, temperature = 60, percent = 10, ckoef = 4.094, density = 1012.5
ID = 8, temperature = 70, percent = 10, ckoef = 4.103, density = 1012.5
ID = 9, temperature = 80, percent = 10, ckoef = 4.113, density = 1012.5
ID = 10, temperature = 90, percent = 10, ckoef = 4.122, density = 1012.5
ID = 11, temperature = 100, percent = 10, ckoef = 4.132, density = 1012.5
等百分比 10 - 50,步长 10
所以请帮忙。
【问题讨论】:
-
怎么不工作了?它在做什么,你想让它做什么?
-
尝试
"temperature = ? AND percent = ?"而不是"temperature, percent = ?" -
E/AndroidRuntime: FATAL EXCEPTION: main 11-20 03:40:36.958 20254-20254/com.example.prog E/AndroidRuntime: Process: com.example.prog, PID: 20254 E/ AndroidRuntime: android.database.sqlite.SQLiteException: near ",": syntax error (code 1): , while compile: SELECT * FROM mytable WHERE temperature, percent = ?
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提图斯,谢谢,成功了!