Android开发error: java.lang.NullPointerExceptio

这个是我遇到的错误

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'int android.widget.ImageView.getWidth()' on a null object reference

造成该错误的源码

int targetW = mImageView.getWidth();

mImageView = (ImageView) findViewById(R.id.imageView1);
mImageView = null;

错误解读

解决方法

mImageView = (ImageView) findViewById(R.id.imageView1);
//mImageView = null;