Java NullPointerException-ParseImageView
尝试从解析中检索信息(如字符串、数字和图像)时,我收到以下错误: 特别是,我收到来自ParseImageView的错误,在这里字符串和数字被很好地检索到。 logcat消息Java NullPointerException-ParseImageView,java,android,android-activity,android-fragments,parse-platform,Java,Android,Android Activity,Android Fragments,Parse Platform,尝试从解析中检索信息(如字符串、数字和图像)时,我收到以下错误: 特别是,我收到来自ParseImageView的错误,在这里字符串和数字被很好地检索到。 logcat消息 08-23 13:25:28.269: E/AndroidRuntime(1377): FATAL EXCEPTION: main 08-23 13:25:28.269: E/AndroidRuntime(1377): Process: com.dooba.beta, PID: 1377 08-23 13:25:28.269
08-23 13:25:28.269: E/AndroidRuntime(1377): FATAL EXCEPTION: main
08-23 13:25:28.269: E/AndroidRuntime(1377): Process: com.dooba.beta, PID: 1377
08-23 13:25:28.269: E/AndroidRuntime(1377): java.lang.NullPointerException
08-23 13:25:28.269: E/AndroidRuntime(1377): at com.dooba.beta.Fragment1$1$1.done(Fragment1.java:184)
08-23 13:25:28.269: E/AndroidRuntime(1377): at com.parse.ParseImageView$1.done(ParseImageView.java:157)
08-23 13:25:28.269: E/AndroidRuntime(1377): at com.parse.GetDataCallback.internalDone(GetDataCallback.java:20)
08-23 13:25:28.269: E/AndroidRuntime(1377): at com.parse.GetDataCallback.internalDone(GetDataCallback.java:1)
08-23 13:25:28.269: E/AndroidRuntime(1377): at com.parse.Parse$6$1.run(Parse.java:888)
08-23 13:25:28.269: E/AndroidRuntime(1377): at android.os.Handler.handleCallback(Handler.java:733)
08-23 13:25:28.269: E/AndroidRuntime(1377): at android.os.Handler.dispatchMessage(Handler.java:95)
08-23 13:25:28.269: E/AndroidRuntime(1377): at android.os.Looper.loop(Looper.java:136)
XML布局
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@drawable/bac_blue"
android:orientation="vertical" >
<Button
android:id="@+id/button1"
android:layout_width="100dp"
android:layout_height="50dp"
android:layout_below="@+id/userlistactivityname"
android:layout_centerHorizontal="true"
android:layout_marginTop="28dp"
android:alpha="0.7"
android:background="#ADD8E6"
android:text="Confirm"
android:textColor="#000000"
android:textSize="22sp"
android:typeface="serif" />
<ListView
android:id="@+id/userlistage"
android:layout_width="220dp"
android:layout_height="50dp"
android:layout_below="@+id/profilePictureresult"
android:layout_marginTop="19dp"
android:layout_toLeftOf="@+id/imageView2"
android:divider="@null" >
</ListView>
<com.parse.ParseImageView
android:id="@+id/profilePictureresult"
android:layout_width="132dp"
android:layout_height="120dp"
android:layout_below="@+id/userlistheadline"
android:layout_centerHorizontal="true"
android:layout_marginTop="17dp"
android:alpha="1"
android:background="@drawable/border_image"
android:cropToPadding="true"
android:padding="3dp"
android:scaleType="centerCrop" />
<ListView
android:id="@+id/userlistname"
android:layout_width="220dp"
android:layout_height="50dp"
android:layout_alignParentTop="true"
android:layout_marginTop="25dp"
android:layout_toRightOf="@+id/imageView1"
android:divider="@null" >
</ListView>
<ImageView
android:id="@+id/imageView2"
android:layout_width="70dp"
android:layout_height="50dp"
android:layout_alignParentRight="true"
android:layout_alignTop="@+id/profilePictureresult"
android:layout_marginTop="16dp"
android:alpha="0.7"
android:src="@drawable/left_right" />
<ImageView
android:id="@+id/imageView1"
android:layout_width="70dp"
android:layout_height="50dp"
android:layout_alignParentLeft="true"
android:layout_alignTop="@+id/imageView2"
android:alpha="0.7"
android:src="@drawable/left_arrow2" />
<ListView
android:id="@+id/userlistheadline"
android:layout_width="220dp"
android:layout_height="50dp"
android:layout_below="@+id/userlistname"
android:layout_marginTop="17dp"
android:layout_toRightOf="@+id/imageView1"
android:divider="@null" >
</ListView>
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/userlistage"
android:layout_centerHorizontal="true"
android:text="Activity Name"
android:textColor="#a2a2a2"
android:textSize="22sp" />
<ListView
android:id="@+id/userlistactivityname"
android:layout_width="220dp"
android:layout_height="50dp"
android:layout_below="@+id/textView1"
android:layout_marginTop="7dp"
android:layout_toLeftOf="@+id/imageView2"
android:divider="@null" >
</ListView>
</RelativeLayout>
例外情况出现在Fragment1.java类的第184行,可能就是这一行:
Log.i("ParseImageView", "Fetched! Data length: " + data.length + ", or exception: " + e.getMessage());
这将始终引发一个NullPointerException
:
如果图像加载正确,数据
将是有效的字节[]
,e
将为null
。因此e.getMessage()
将抛出NullPointerException
如果图像未正确加载,数据
将为空
,e
将是有效的异常
,因此数据.length
将抛出空点异常
您可能想做的是:
if (data != null) {
Log.i("ParseImageView", "Fetched: " + data.length);
} else {
Log.e("ParseImageView", "Error fetching: " + e.getMessage());
}
请发布日志跟踪。
Log.i("ParseImageView", "Fetched! Data length: " + data.length + ", or exception: " + e.getMessage());
if (data != null) {
Log.i("ParseImageView", "Fetched: " + data.length);
} else {
Log.e("ParseImageView", "Error fetching: " + e.getMessage());
}