Java 布局和鼠标事件
我正在尝试用SWT创建一个自定义滑块,但我有一个奇怪的结果,我希望我在这里遗漏了一些东西,我希望有一个内部画布的合成,它有一个大约15个顶部、左右和底部的边距。 类似于此: 所以我写了一个这样的主旋律: Main.javaJava 布局和鼠标事件,java,events,layout,swt,Java,Events,Layout,Swt,我正在尝试用SWT创建一个自定义滑块,但我有一个奇怪的结果,我希望我在这里遗漏了一些东西,我希望有一个内部画布的合成,它有一个大约15个顶部、左右和底部的边距。 类似于此: 所以我写了一个这样的主旋律: Main.java import org.eclipse.swt.SWT; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widg
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;
public class Main {
public static void main (String [] args) {
Display display = new Display ();
Shell shell = new Shell(display);
shell.setLayout(new GridLayout(1,false));
shell.setSize(400,400);
CustomSlider slider= new CustomSlider(shell, SWT.NONE);
shell.pack();
shell.open ();
while (!shell.isDisposed ()) {
if (!display.readAndDispatch ()) display.sleep ();
}
display.dispose ();
}
}
以及扩展Composite的customSlider类:
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Widget;
public class CustomSlider extends Composite {
private Canvas progressBar;
private Rectangle progressBarRect;
private int knobSize=15;
private Point thisSize;
private boolean hover=false;
public CustomSlider(Composite arg0, int arg1) {
super(arg0, arg1);
thisSize= new Point(400, 50);
setSize(400, 50);
setBackground(arg0.getDisplay().getSystemColor(SWT.COLOR_MAGENTA));
GridLayout gl= new GridLayout(1,false);
setLayout(gl);
setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
progressBar = new Canvas(this, SWT.NONE);
GridLayout gl2= new GridLayout(1,false);
gl2.marginBottom=knobSize;
gl2.marginTop=knobSize;
gl2.marginLeft=knobSize;
gl2.marginRight=knobSize;
gl2.marginWidth=knobSize;
gl2.marginHeight=knobSize;
progressBar.setLayout(gl2);
GridData gd=new GridData(SWT.FILL, SWT.FILL, true, true);
progressBar.setLayoutData(gd);
progressBar.addPaintListener(new PaintListener() {
@Override
public void paintControl(PaintEvent arg0) {
Canvas canvasProgress=(Canvas)arg0.widget;
progressBarRect= canvasProgress.getBounds();
GC gc=arg0.gc;
gc.setForeground(canvasProgress.getDisplay().getSystemColor(SWT.COLOR_GREEN));
if (hover){
gc.setBackground(canvasProgress.getDisplay().getSystemColor(SWT.COLOR_RED));
}else{
gc.setBackground(canvasProgress.getDisplay().getSystemColor(SWT.COLOR_BLUE));
}
gc.fillRectangle(progressBarRect);
gc.drawRectangle(progressBarRect);
}
});
Listener listener = new Listener() {
public void handleEvent(Event event) {
System.out.println("---------------");
System.out.println("Canvas:"+((Canvas)event.widget).getBounds());
System.out.println("Composite:"+((Canvas)event.widget).getParent().getBounds());
System.out.println("Shell:"+((Canvas)event.widget).getParent().getParent().getBounds());
Display display=((Widget)event.widget).getDisplay();
switch (event.type) {
case SWT.MouseHover:
if (progressBarRect.contains(new Point(event.x, event.y))){
hover=true;
}else{
hover=false;
}
break;
case SWT.MouseDown:
break;
case SWT.MouseMove:
if (progressBarRect.contains(new Point(event.x, event.y))){
hover=true;
}else{
hover=false;
}
break;
case SWT.MouseEnter:
if (progressBarRect.contains(new Point(event.x, event.y))){
hover=true;
}else{
hover=false;
}
break;
case SWT.MouseExit:
if (progressBarRect.contains(new Point(event.x, event.y))){
System.out.println("progressBarRect:"+progressBarRect);
System.out.println("Point"+new Point(event.x, event.y));
System.out.println("HOVER!");
hover=true;
}else{
System.out.println("OUT!");
hover=false;
}
break;
case SWT.MouseUp:
break;
}
display.asyncExec(() -> progressBar.redraw());
}
};
progressBar.addListener(SWT.MouseDown, listener);
progressBar.addListener(SWT.MouseUp, listener);
progressBar.addListener(SWT.MouseMove, listener);
progressBar.addListener(SWT.MouseExit, listener);
progressBar.addListener(SWT.MouseEnter, listener);
progressBar.addListener(SWT.MouseHover, listener);
}
public Point getThisSize() {
return thisSize;
}
public void setThisSize(Point thisSize) {
this.thisSize = thisSize;
}
}
现在,第一件事是结果与我想要的不匹配,似乎没有考虑利润,或者最好只考虑两个(顶部和左侧):
其次,这些事件会导致意外的结果:MouseExit事件说我仍然在画布上悬停,即使我不在合成中!:
你能帮我了解一下这里发生了什么事吗
提前谢谢你
编辑
根据Greg的建议,我编辑代码如下:
主要内容:
然后自定义滑块变为自定义滑块2:
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Widget;
public class CustomSlider2 extends Composite {
private Canvas progressBar;
private Rectangle progressBarRect;
private int knobSize=15;
private boolean hover=false;
public CustomSlider2(Composite arg0, int arg1) {
super(arg0, arg1);
setBackground(arg0.getDisplay().getSystemColor(SWT.COLOR_MAGENTA));
setLayout(new GridLayout(1,false));
progressBar = new Canvas(this, SWT.CENTER);
final GridData gd=new GridData(SWT.FILL, SWT.FILL, true, true);
gd.widthHint = 100;
gd.heightHint = 50;
GridLayout gl= new GridLayout();
gl.numColumns=1;
gl.marginWidth=knobSize;
gl.marginHeight=knobSize;
progressBar.setLayoutData(gd);
progressBar.setLayout(gl);
progressBar.addPaintListener(new PaintListener() {
@Override
public void paintControl(PaintEvent arg0) {
Canvas canvasProgress=(Canvas)arg0.widget;
Rectangle clientArea= canvasProgress.getBounds();
progressBarRect=new Rectangle(clientArea.x, clientArea.y, clientArea.x + clientArea.width - 1, clientArea.y + clientArea.height - 1);
GC gc=arg0.gc;
gc.setForeground(canvasProgress.getDisplay().getSystemColor(SWT.COLOR_GREEN));
if (hover){
gc.setBackground(canvasProgress.getDisplay().getSystemColor(SWT.COLOR_RED));
}else{
gc.setBackground(canvasProgress.getDisplay().getSystemColor(SWT.COLOR_BLUE));
}
gc.fillRectangle(progressBarRect);
gc.drawRectangle(progressBarRect);
}
});
Listener listener = new Listener() {
public void handleEvent(Event event) {
System.out.println("---------------");
System.out.println("Canvas:"+((Canvas)event.widget).getBounds());
System.out.println("Composite:"+((Canvas)event.widget).getParent().getBounds());
System.out.println("Shell:"+((Canvas)event.widget).getParent().getParent().getBounds());
Display display=((Widget)event.widget).getDisplay();
switch (event.type) {
case SWT.MouseEnter:
hover=true;
break;
case SWT.MouseExit:
hover=false;
break;
}
display.asyncExec(() -> progressBar.redraw());
}
};
progressBar.addListener(SWT.MouseExit, listener);
progressBar.addListener(SWT.MouseEnter, listener);
}
}
因此,事件问题似乎是固定的,但不是布局问题。。。我仍然没有画布周围的边距…使用布局时,可以使用布局宽度和高度提示为控件设置建议的大小。因此,在这里您可以使用:
final GridData gd=new GridData(SWT.FILL, SWT.FILL, true, true);
gd.widthHint = 400;
gd.heightHint = 50;
progressBar.setLayoutData(gd);
在paintControl
中,您使用的是getBounds
,它提供控件的完整大小,包括布局添加的边框。但是像fillRectangle
这样的操作总是在“客户区”中绘制,而不包括边框。所以你的油漆应该是这样的:
@Override
public void paintControl(PaintEvent event) {
Canvas canvasProgress = (Canvas)event.widget;
Rectangle clientArea = canvasProgress.getClientArea(); // Client area
.. set colors
gc.fillRectangle(clientArea.x, clientArea.y, clientArea.x + clientArea.width - 1, clientArea.y + clientArea.height - 1);
gc.drawRectangle(clientArea.x, clientArea.y, clientArea.x + clientArea.width - 1, clientArea.y + clientArea.height - 1);
}
对于鼠标移动,无需检查事件中的位置。只有当鼠标离开控件时才会调用MouseExit。不要将
setSize
(或setBounds
)与布局混合-布局将覆盖大小。您好,Greg,但我没有混合,我使用了组合的设置大小(CustomSlider)让SWT决定画布的边界,但我告诉SWT使用画布的网格布局,以便四周都有边距。。。这有什么问题?我已经做了一个测试,甚至在合成图上注释了setSize。结果没有改变,只考虑顶部和左侧的边距…:(你的shell有一个GridLayout,它会覆盖CustomSlider的大小。我不是说这是这里唯一的问题。嗨,Greg,因为没有显示布局的组合,这意味着永远不应该在它上面使用setSize?对我来说这听起来很奇怪…很抱歉这个愚蠢的问题,但我正在努力学习…嗨,Greg,事件的问题似乎是这样的。)要修复,但不是布局…我仍然没有画布周围的边距…(我用新代码编辑了我的问题…)您仍然在paintControl
中使用getBounds
,这必须是getclientrea
。
@Override
public void paintControl(PaintEvent event) {
Canvas canvasProgress = (Canvas)event.widget;
Rectangle clientArea = canvasProgress.getClientArea(); // Client area
.. set colors
gc.fillRectangle(clientArea.x, clientArea.y, clientArea.x + clientArea.width - 1, clientArea.y + clientArea.height - 1);
gc.drawRectangle(clientArea.x, clientArea.y, clientArea.x + clientArea.width - 1, clientArea.y + clientArea.height - 1);
}