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;
}