How to call Z-functions from a plugin on ImageJ - plugins

Question

Good Morning
I'm currently doing a plugIn for ImageJ in JAVA that needs to call the function "Maximum Intensity Z-projection", which I know that is already in ImageJ if you go for "Image/Stacks/Z Project...". Documentation here: http://imagej.net/Z-functions#Maximum_Intensity_Z-projection
I know how to call plugins from another plugins, but doing the same thing in this case I get all the time my "Error" message.
public class Maximum_Intensity implements PlugIn{
ImagePlus img = WindowManager.getCurrentImage();
#Override
public void run(String arg0) {
// TODO Auto-generated method stub
Object ZProjector = null;
ZProjector = IJ.runPlugIn(img, "ZProjector", arg0);
if(ZProjector==null){
String arg = "Error";
IJ.showMessage(arg);
}
}
}
How can I do it? Thank you so much.

Answer 1

You can easily use the macro recorder for help to record all commands in ImageJ, see:
https://imagej.nih.gov/ij/docs/guide/146-31.html#sub:Record...
Enable Java for the recorder and then use the "Create" action to create an ImageJ plugin from the recorded interface actions.
In the following example (created with the Recorder) I applied the Max. Intensity function on a stack.
import ij.*;
import ij.process.*;
import ij.gui.*;
import java.awt.*;
import ij.plugin.*;
public class My_Plugin implements PlugIn {
public void run(String arg) {
ImagePlus imp = IJ.openImage("http://imagej.nih.gov/ij/images/mri-stack.zip");
IJ.run(imp, "Z Project...", "projection=[Max Intensity]");
imp.show();
}
}
The ZProjector class description can be found here (for instantiation):
https://imagej.nih.gov/ij/developer/api/ij/plugin/ZProjector.html