我正在尝试为我的地图集群设置视图.
我正在从 XML膨胀视图并根据群集大小设置文本,我想显示该视图.
在下面的代码中我得到一个空位图作为回报:
我正在从 XML膨胀视图并根据群集大小设置文本,我想显示该视图.
在下面的代码中我得到一个空位图作为回报:
private Bitmap createClusterBitmap(int clusterSize) { View cluster = LayoutInflater.from(context).inflate(R.layout.map_cluster,null); cluster.setText(String.valueOf(clusterSize)); cluster.setDrawingCacheEnabled(true); cluster.buildDrawingCache(true); Bitmap bm = cluster.getDrawingCache(); return bm; }
在下面的代码中我得到第四行的空指针(布局参数):
private Bitmap createClusterBitmap(int clusterSize) { View cluster = LayoutInflater.from(context).inflate(R.layout.map_cluster,null); TextView clusterSizeText = (TextView) cluster.findViewById(R.map.cluster); clusterSizeText.setText(String.valueOf(clusterSize)); Bitmap clusterBitmap = Bitmap.createBitmap( cluster.getLayoutParams().width,cluster.getLayoutParams().height,Bitmap.Config.ARGB_8888); Canvas clusterCanvas = new Canvas(clusterBitmap); cluster.layout(cluster.getLeft(),cluster.getTop(),cluster.getRight(),cluster.getBottom()); cluster.draw(clusterCanvas); return clusterBitmap; }
当将其更改为以下代码时,我得到的不是错误,但没有绘制任何内容:
private Bitmap createClusterBitmap(int clusterSize) { View cluster = LayoutInflater.from(context).inflate(R.layout.map_cluster,null); TextView clusterSizeText = (TextView) cluster.findViewById(R.map.cluster); clusterSizeText.setText(String.valueOf(clusterSize)); Bitmap clusterBitmap = Bitmap.createBitmap( 50,50,Bitmap.Config.ARGB_8888); Canvas clusterCanvas = new Canvas(clusterBitmap); cluster.layout(50,50; cluster.draw(clusterCanvas); return clusterBitmap; }
这是我的XML:
<?xml version="1.0" encoding="utf-8"?> <TextView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+map/cluster" android:layout_width="wrap_content" android:layout_height="wrap_content" android:background="@drawable/map_pointer_cluster" android:gravity="center" android:orientation="vertical" android:textColor="@android:color/black" android:textSize="35dp" android:textStyle="bold" />
解决方法
您的cluster.getLayoutParams()可能为null.首先,您需要测量膨胀视图的宽度/高度,然后分配给它.做如下:
private Bitmap createClusterBitmap(int clusterSize) { View cluster = LayoutInflater.from(context).inflate(R.layout.map_cluster,null); TextView clusterSizeText = (TextView) cluster.findViewById(R.id.map_cluster_text); clusterSizeText.setText(String.valueOf(clusterSize)); cluster.measure(MeasureSpec.makeMeasureSpec(0,MeasureSpec.UNSPECIFIED),MeasureSpec.makeMeasureSpec(0,MeasureSpec.UNSPECIFIED)); cluster.layout(0,cluster.getMeasuredWidth(),cluster.getMeasuredHeight()); final Bitmap clusterBitmap = Bitmap.createBitmap(cluster.getMeasuredWidth(),cluster.getMeasuredHeight(),Bitmap.Config.ARGB_8888); Canvas canvas = new Canvas(clusterBitmap); cluster.draw(canvas); return clusterBitmap; }