Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>I think your issue is with the way your ClickHandler is implemented as an anonymous inner class. At the point when <code>Test</code> method is executed, <code>this</code> has no meaning anymore. You need to rewrite your ClickHandler to hold an instance to your class:</p> <pre><code>public class testscan implements EntryPoint { public static class MyClickHandler implements ClickHandler { testscan instance; public MyClickHandler(testscan instance) { this.instance = instance; } public void onClick(ClickEvent event) { this.instance.x(); } } private Image image_0 = new Image("home.gif"); public void onModuleLoad() { RootPanel rootPanel = RootPanel.get("main_panel"); rootPanel.getElement().getStyle().setPosition(Position.RELATIVE); VerticalPanel verticalPanel = new VerticalPanel(); rootPanel.add(verticalPanel, 5, 5); verticalPanel.setSize("100%", "100%"); HorizontalPanel horizontalPanel = new HorizontalPanel(); verticalPanel.add(horizontalPanel); horizontalPanel.setSize("100%", "100%"); Image image_1 = new Image("home.gif"); horizontalPanel.add(image_1); image_1.setSize("180px", "180px"); horizontalPanel.add(image_0); image_0.setSize("180px", "180px"); Image image_2 = new Image("home.gif"); horizontalPanel.add(image_2); image_2.setSize("180px", "180px"); Button btnScan = new Button("Scan"); verticalPanel.add(btnScan); btnScan.addClickHandler(new MyClickHandler(this)); } public void x() { Test(this); } public native void Test(testscan instance) /*-{ instance.@com.sflpro.testscan.client.testscan::updateImageContent()(); }-*/; public void updateImageContent() { Window.alert("ok"); //String s = scanFileContent(); //Window.alert(s); if(image_0==null) Window.alert("bad"); else Window.alert("good"); } } </code></pre> <p>I mean this whole way you are going about it is a bit strange, but I understand you are just learning and this is just a test app you are playing around with. Normally you wouldn't have this type of code in your EntryPoint class.</p>
    singulars
    1. This table or related slice is empty.
    1. POCall Java from JavaScript gwt
      singulars
      1. PTQuestion
    1. PTAnswer
    1. This table or related slice is empty.
    1. USStrelok
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. COActually, I don't see how your code changes anything: the x() call in Vasil's code is actually testscan.this.x() (the anonymous inner class has an implicit reference to its parent testscan instance, which is equivalent to using a 'static' nested class initialized explicitly with the testscan instance), so there's no reason it wouldn't work (apart from a bug in the GWT compiler optimizations, which your code might not trigger)
      singulars
      1. PO
      1. USThomas Broyer
    2. COYou are right, I think it is a bug. This code running in java with normal java methods should work. I wonder if it should work in hosted mode as well. I didn't test the code that I wrote but if it is a bug in GWT as you said it shouldn't trigger it because there is a reference to "this" in the click handler. Could the compiler be running into the common Javascript mistake with closures?
      singulars
      1. PO
      1. USStrelok
    3. COThanks for the answers, I think it's a bug in GWT. do you have any suggestion workaround for this kind of tasks?
      singulars
      1. PO
      1. USVasil Mamikonyan
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload