NullPointerException:Attempt to invoke virtual method 'double java.lang.Double.doubleValue()' on ..
2018-01-26 16:42
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今天在开发过程中,加载界面,然后在初始化数据的时候报错“ Caused by: java.lang.NullPointerException:
Attempt to invoke virtual method 'double java.lang.Double.doubleValue()' on a null object reference”。定位报错代码到对应的行数:
private Double totalExpenses; //提前声明好了变量
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_decoration_bills);
.......
totalExpenses = totalExpenses + pay;
.......
}
这是因为 声明的全局变量totalExpenses,没有初始化。改成:初始化就好了 就不会报空指针了
private Double totalExpenses = 0.0;
这些小的细节很重要。
Attempt to invoke virtual method 'double java.lang.Double.doubleValue()' on a null object reference”。定位报错代码到对应的行数:
private Double totalExpenses; //提前声明好了变量
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_decoration_bills);
.......
totalExpenses = totalExpenses + pay;
.......
}
这是因为 声明的全局变量totalExpenses,没有初始化。改成:初始化就好了 就不会报空指针了
private Double totalExpenses = 0.0;
这些小的细节很重要。
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