Question

我的应用中有一个简单的 if-else 语句，但它不起作用。如果我在 Spinner 中选择“天”，则只能编辑该日。它不起作用，因为仍然可以编辑所有日子。有人可以告诉我为什么吗？

final String[] items={"Day","Date","Time","Location"};

    mSpin2.setOnItemSelectedListener(
        new OnItemSelectedListener() {
            @Override
            public void onItemSelected(
                AdapterView<?> parent2, View view, int pos, long id
            ) {
String strsel=items[pos];
if(strsel.equalsIgnoreCase("Day")) {
    btnChangeDate.setFocusable(false);
    btnChangeDate.setEnabled(false);
    //btnChangeDate.setClickable(false);
    btnChangeTime.setFocusable(false);
    btnChangeTime.setEnabled(false);
    //btnChangeTime.setClickable(false);
    mLatitude.setFocusable(false);
    mLatitude.setEnabled(false);
    mLongitude.setFocusable(false);
    mLongitude.setEnabled(false);
} else {
    mMonday.setFocusable(true);
    mMonday.setEnabled(true);
    mTuesday.setFocusable(true);
    mTuesday.setEnabled(true);
    mWednesday.setFocusable(true);
    mWednesday.setEnabled(true);
    mThursday.setFocusable(true);
    mThursday.setEnabled(true);
    mFriday.setFocusable(true);
    mFriday.setEnabled(true);
    mSaturday.setFocusable(true);
    mSaturday.setEnabled(true);
    mSunday.setFocusable(true);
    mSunday.setEnabled(true);
} 

String strsel2=items[pos];
if(strsel2.equalsIgnoreCase("Date")) {
    mMonday.setFocusable(false);
    mMonday.setEnabled(false);
    mTuesday.setFocusable(false);
    mTuesday.setEnabled(false);
    mWednesday.setFocusable(false);
    mWednesday.setEnabled(false);
    mThursday.setFocusable(false);
    mThursday.setEnabled(false);
    mFriday.setFocusable(false);
    mFriday.setEnabled(false);
    mSaturday.setFocusable(false);
    mSaturday.setEnabled(false);
    mSunday.setFocusable(false);
    mSunday.setEnabled(false);
    btnChangeTime.setFocusable(false);
    btnChangeTime.setEnabled(false);
    //btnChangeTime.setClickable(false);
    mLatitude.setFocusable(false);
    mLatitude.setEnabled(false);
    mLongitude.setFocusable(false);
    mLongitude.setEnabled(false);                           
} else {
    btnChangeDate.setFocusable(true);
    btnChangeDate.setEnabled(true);
}

String strsel3=items[pos];
if(strsel3.equalsIgnoreCase("Time")) {
    mMonday.setFocusable(false);
    mMonday.setEnabled(false);
    mTuesday.setFocusable(false);
    mTuesday.setEnabled(false);
    mWednesday.setFocusable(false);
    mWednesday.setEnabled(false);
    mThursday.setFocusable(false);
    mThursday.setEnabled(false);
    mFriday.setFocusable(false);
    mFriday.setEnabled(false);
    mSaturday.setFocusable(false);
    mSaturday.setEnabled(false);
    mSunday.setFocusable(false);
    mSunday.setEnabled(false);
    btnChangeDate.setFocusable(false);
    btnChangeDate.setEnabled(false);
    //btnChangeDate.setClickable(false);
    mLatitude.setFocusable(false);
    mLatitude.setEnabled(false);
    mLongitude.setFocusable(false);
    mLongitude.setEnabled(false);
} else {
    btnChangeTime.setFocusable(true);
    btnChangeTime.setEnabled(true);
}

String strsel4=items[pos];
if(strsel.equalsIgnoreCase("Location")) {
    mMonday.setFocusable(false);
    mMonday.setEnabled(false);
    mTuesday.setFocusable(false);
    mTuesday.setEnabled(false);
    mWednesday.setFocusable(false);
    mWednesday.setEnabled(false);
    mThursday.setFocusable(false);
    mThursday.setEnabled(false);
    mFriday.setFocusable(false);
    mFriday.setEnabled(false);
    mSaturday.setFocusable(false);
    mSaturday.setEnabled(false);
    mSunday.setFocusable(false);
    mSunday.setEnabled(false);
    btnChangeDate.setFocusable(false);
    btnChangeDate.setEnabled(false);
    //btnChangeDate.setClickable(false);
btnChangeTime.setFocusable(false);
btnChangeTime.setEnabled(false);
//btnChangeTime.setClickable(false);
} else {
    //mLatitude.setFocusable(true);
    mLatitude.setEnabled(true);
    //mLongitude.setFocusable(true);
    mLongitude.setEnabled(true);
} 
}

@Override
public void onNothingSelected(AdapterView<?> arg0) {}
    }
);

Answer 1

好的，我再次查看了你的代码。你要么做一些不明显的事情，要么你没有使用else案例，因为它应该被使用。无论如何，你知道你得到的结果是错误的。我建议在下面的模式之后重写监听器。您可能需要根据实际要求对其进行微调：

static final int dayIndex  = 0;
static final int dateIndex = 1;
static final int timeIndex = 2;
static final int locIndex  = 3;

public void onItemSelected( AdapterView<?> parent2, View view, int pos, long id ) {
    mMonday.setFocusable( pos == dayIndex );
    mMonday.setEnabled( pos == dayIndex );
    mTuesday.setFocusable( pos == dayIndex );
    mTuesday.setEnabled( pos == dayIndex );
    mWednesday.setFocusable( pos == dayIndex );
    mWednesday.setEnabled( pos == dayIndex );
    mThursday.setFocusable( pos == dayIndex );
    mThursday.setEnabled( pos == dayIndex );
    mFriday.setFocusable( pos == dayIndex );
    mFriday.setEnabled( pos == dayIndex );
    mSaturday.setFocusable( pos == dayIndex );
    mSaturday.setEnabled( pos == dayIndex );
    mSunday.setFocusable( pos == dayIndex );
    mSunday.setEnabled( pos == dayIndex );

    btnChangeDate.setFocusable( pos == dateIndex );
    btnChangeDate.setEnabled( pos == dateIndex );

    btnChangeTime.setFocusable( pos == timeIndex );
    btnChangeTime.setEnabled( pos == timeIndex );

    mLatitude.setEnabled( pos == locIndex );
    mLongitude.setEnabled( pos == locIndex );
}

如果您在微调器中选择第一个项目（Day），则上面的代码将启用mMonday..mSunday，否则禁用它们。如果你选择第二项（日期）......它会启用btnChangeDate。请注意，如果我猜对了你的意图，并且这段代码有效，那么你对if / then / else结构的理解是非常有缺陷的，你可能会我想读一读。

If-Else语句在Android应用中无效

1 个答案: