如何编写一个对调整大小做出反应的小部件?
以下不起作用。 onResize()在开头只调用一次。更改后的浏览器窗口大小不会导致调用此方法,尽管调整了DIV的大小。
public class MyWidget extends SimpleLayoutPanel {
private Label label;
public MyWidget() {
label = new Label("A");
add(label);
}
@Override
public void onResize() {
super.onResize();
int width = label.getElement().getClientWidth();
int height = label.getElement().getClientHeight();
int fontsize = (width>height?height:width);
if( fontsize > 0 ) {
DOM.setStyleAttribute(label.getElement(), "font-size", Integer.toString(fontsize)+"px");
}
}
}
和主要模块
public void onModuleLoad() {
MyWidget myWidget = new MyWidget();
DOM.setStyleAttribute(myWidget.getElement(), "position", "fixed");
DOM.setStyleAttribute(myWidget.getElement(), "top", "0px");
DOM.setStyleAttribute(myWidget.getElement(), "left", "0px");
DOM.setStyleAttribute(myWidget.getElement(), "bottom", "0px");
DOM.setStyleAttribute(myWidget.getElement(), "right", "0px");
RootPanel rootPanel = RootPanel.get();
rootPanel.add(myWidget);
}
更新1
基于ResizComposite的版本也不起作用。在这种情况下,onResize从未调用过。
public class MyWidget extends ResizeComposite {
private Label label;
public MyWidget() {
label = new Label("A");
DOM.setStyleAttribute(label.getElement(), "position", "fixed");
DOM.setStyleAttribute(label.getElement(), "top", "0px");
DOM.setStyleAttribute(label.getElement(), "left", "0px");
DOM.setStyleAttribute(label.getElement(), "bottom", "0px");
DOM.setStyleAttribute(label.getElement(), "right", "0px");
SimpleLayoutPanel simpleLayoutPanel = new SimpleLayoutPanel();
simpleLayoutPanel.add(label);
initWidget(simpleLayoutPanel);
}
@Override
public void onResize() {
int width = label.getElement().getClientWidth();
int height = label.getElement().getClientHeight();
int fontsize = (width>height?height:width);
if( fontsize > 0 ) {
DOM.setStyleAttribute(label.getElement(), "font-size", Integer.toString(fontsize)+"px");
}
super.onResize();
}
}
答案 0 :(得分:1)
您必须添加ProvidesResize
小部件(RootLayoutPanel
,ResizeLayoutPanel
)或HeaderPanel
才能获得荣誉RequiresResize
。见http://code.google.com/webtoolkit/doc/latest/DevGuideUiPanels.html#Resize