小编Sud*_*esh的帖子

我在列表视图上有一个浮动操作按钮,但是当列表填满时我无法单击该按钮,以便按钮和列表重叠.在那种情况下,只有列表项是可点击的.我该如何纠正这个问题？提前致谢.我的xml代码如下.

    <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">


<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:id="@+id/card_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_margin="3dp"
    android:paddingBottom="10dp"
    android:paddingLeft="10dp"
    android:paddingRight="10dp"
    android:paddingTop="10dp"
    card_view:cardCornerRadius="1dp"
    card_view:cardElevation="5dp">

    <RelativeLayout
        android:id="@+id/layout"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_below="@+id/frameLayout"
        android:layout_centerHorizontal="true"
        android:layout_gravity="bottom"
        android:background="#000000"
        android:orientation="vertical"
        android:padding="1.5dp"
        android:weightSum="1">


        <TextView
            android:id="@+id/txtTitle"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentStart="true"
            android:layout_alignParentTop="true"
            android:background="#660033"
            android:text="Large Text"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:textColor="@android:color/primary_text_dark" />

        <RelativeLayout
            android:id="@+id/frameLayout"
            android:layout_width="fill_parent"
            android:layout_height="300dp"
            android:layout_alignParentStart="true"
            android:layout_alignParentTop="true"
            android:layout_marginTop="29dp"
            android:background="@android:color/darker_gray"
            android:padding="2dp">

            <TextView
                android:id="@+id/txtLocation"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentStart="true"
                android:layout_below="@+id/dispLoc"
                android:layout_gravity="left|top"
                android:text="[Location]"
                android:textAppearance="?android:attr/textAppearanceMedium" />

            <TextView
                android:id="@+id/txtDesc"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentStart="true"
                android:layout_below="@+id/dispDesc"
                android:layout_gravity="left|center_vertical"
                android:layout_marginTop="1dp"
                android:text="[Description]"
                android:textAppearance="?android:attr/textAppearanceMedium" />

            <TextView
                android:id="@+id/dispLoc"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentStart="true"
                android:layout_alignParentTop="true" …

我在尝试压缩位图时遇到空指针异常,因此我可以将其发送到ByteArrayOutputStream以获取字节数组.我需要这个字节数组,所以我可以将图像作为ParseFile上传到我的Parse数据库.日志错误如下所示.

01-11 23:29:41.522 32015-32015/com.example.whhsfbla.fashionnow E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.whhsfbla.fashionnow, PID: 32015
java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.graphics.Bitmap.compress(android.graphics.Bitmap$CompressFormat, int, java.io.OutputStream)' on a null object reference
    at com.example.whhsfbla.fashionnow.PostActivity.uploadPost(PostActivity.java:140)
    at com.example.whhsfbla.fashionnow.PostActivity.access$100(PostActivity.java:34)
    at com.example.whhsfbla.fashionnow.PostActivity$2.onClick(PostActivity.java:92)
    at android.view.View.performClick(View.java:5254)
    at android.view.View$PerformClick.run(View.java:21179)
    at android.os.Handler.handleCallback(Handler.java:739)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:145)
    at android.app.ActivityThread.main(ActivityThread.java:6837)
    at java.lang.reflect.Method.invoke(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:372)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)

导致错误的行是 bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);

    public class PostActivity extends Activity {

    private final int SELECT_PHOTO = 1;
    private InputStream imageStream;
    private Uri uploadFileUri;
    private Bitmap bitmap;
    private …