java.lang.NullPointerException：尝试在空对象引用上调用虚拟方法“void android.widget.ImageView.setImageResource(int)”
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java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ImageView.setImageResource(int)' on a null object reference
提问by jDmendiola
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ImageView.setImageResource(int)' on a null object reference
java.lang.NullPointerException：尝试在空对象引用上调用虚拟方法“void android.widget.ImageView.setImageResource(int)”
I want to make the icon/image of the first activity transfer or move to the second activity but this error above show up.
我想让第一个活动的图标/图像转移或移动到第二个活动，但出现上述错误。
This is my source code in the first actvty:
这是我在第一个活动中的源代码：
public void next (View view){
Intent intent = new Intent(this, Products.class);
intent.putExtra("Button ID", btnId);
startActivity(intent);
}
then in the Second actvty
然后在第二个活动中
btnId = getIntent().getIntExtra("Button ID", btnId);
setContentValues();
}
private void setContentValues() {
ImageView titleImg = (ImageView) findViewById(R.id.imageView_result_title);
View view = (View)findViewById(R.id.layout_goals_goals);
switch (btnId) {
case R.id.imageButton_goals_car:
titleImg.setImageResource(R.drawable.car);
break;
case R.id.imageButton_goals_education:
titleImg.setImageResource(R.drawable.education);
break;
case R.id.imageButton_goals_health:
titleImg.setImageResource(R.drawable.health);
break;
case R.id.imageButton_goals_house:
titleImg.setImageResource(R.drawable.house);
break;
case R.id.imageButton_goals_saving:
titleImg.setImageResource(R.drawable.savings);
break;
case R.id.imageButton_goals_travel:
titleImg.setImageResource(R.drawable.travel);
break;
default:
break;
}
}
采纳答案by Robo
The variable titleImg is possibly null. You should debug into the function to see if it's actually found from the first statement in setContentValues() or not.
变量 titleImg 可能为空。您应该调试该函数以查看它是否确实是从 setContentValues() 中的第一条语句中找到的。
