这是您的AppFrame
.
您可以使用线程运行测试:
java SplashTest true
或没有
java SplashTest
启用线程后,您会看到每 250 毫秒更新一次SplashFrame
,AppFrame
或多或少。
未启用线程时,您会看到SplashFrame
没有显示组件,应用程序“挂起”4 秒钟,然后您会看到AppFrame
.
这个例子有点做作,但可能会给你一些想法。
请注意, 与SplashFrame
没有“直接”连接AppFrame
。所有的通信都是通过AppFrameWorkListener
接口进行的。
我也把“工作”放在了AppFrame
. 但实际上,如果有很多处理要完成,它应该从 UI 代码中提取出来,在单独Thread
的.AppFrame
SplashFrame
import javax.swing.*;
class SplashTest {
static boolean useThread = false;
public static void main(String[] args) {
// Pass true at the command line to turn on threading.
// No args, or any value other than true will turn off threading.
if (args.length > 0) {
useThread = new Boolean(args[0]);
}
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
SplashFrame splashFrame = new SplashFrame();
splashFrame.setVisible(true);
new AppFrame(splashFrame).setVisible(true);
}});
}
private static class BaseFrame extends JFrame {
public BaseFrame() {
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
setSize(200, 200);
setTitle(getClass().getSimpleName());
}
}
private static class SplashFrame extends BaseFrame implements AppFrameWorkListener {
JLabel status;
public SplashFrame() {
setLocation(0, 0);
status = new JLabel("Splash Frame");
getContentPane().add(status);
}
public void appFrameWorkStart() {
status.setText("Work started");
}
public void appFrameWorkProgress(long timeElapsed) {
status.setText("Work has taken " + timeElapsed + "ms so far");
}
public void appFrameWorkDone() {
// http://stackoverflow.com/questions/1234912/how-to-programmatically-close-a-jframe
setVisible(false);
dispose();
}
}
private static class AppFrame extends BaseFrame {
JLabel status;
AppFrameWorkListener listener;
public AppFrame(AppFrameWorkListener listener) {
setLocation(200, 200);
status = new JLabel("App Frame");
getContentPane().add(status);
this.listener = listener;
// None of this 'heavy lifting' should be in a constructor.
if (useThread) {
new Thread(new Runnable() {
@Override
public void run() {
doLotsOfWork(4);
}
}).start();
} else {
doLotsOfWork(4);
onWorkDone();
}
}
private void doLotsOfWork(int workLengthSeconds) {
// We're starting. Ensure onWorkStart is called on the EDT,
// as this method may be called from a different Thread.
invokeOnWorkStartOnEDT();
long start = System.currentTimeMillis();
// Hammer the CPU for "workLengthSeconds" number of seconds.
// And do some contrived progress reporting.
long workLengthMs = workLengthSeconds * 1000;
while (System.currentTimeMillis() - start < workLengthMs) {
long innerStart = System.currentTimeMillis();
// Consume 250ms CPU before issuing progress update.
while (System.currentTimeMillis() - innerStart < 250);
invokeOnWorkProgressOnEDT(System.currentTimeMillis() - start);
}
// We're done now. Ensure onWorkDone is called on the EDT,
// as this method may be called from a different Thread.
invokeOnWorkDoneOnEDT();
}
private void invokeOnWorkStartOnEDT() {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
onWorkStart();
}
});
}
private void invokeOnWorkProgressOnEDT(final long timeElapsed) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
onWorkProgress(timeElapsed);
}
});
}
private void invokeOnWorkDoneOnEDT() {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
onWorkDone();
}
});
}
private void onWorkStart() {
status.setText("Work Started");
if (null != listener) {
// Tell someone who's interested in the work status.
listener.appFrameWorkStart();
}
}
private void onWorkProgress(long timeElapsed) {
status.setText("Work has taken " + timeElapsed + "ms so far");
if (null != listener) {
// Tell someone who's interested in the work status.
listener.appFrameWorkProgress(timeElapsed);
}
}
private void onWorkDone() {
status.setText("Work Done");
if (null != listener) {
// Tell someone who's interested in the work status.
listener.appFrameWorkDone();
}
}
}
interface AppFrameWorkListener {
public void appFrameWorkDone();
public void appFrameWorkStart();
public void appFrameWorkProgress(long timeElapsed);
}
}