为什么我无法从一个对话框创建另一个对话框？

Question

在我的应用程序中，我需要打开一个对话框。在按下该对话框上的按钮时，我想打开另一个对话框并执行一些操作。 这两个对话框都是自定义对话框。 但是，当我这样做时，我无法创建对话框...

请参见下面的代码：

twsbiImageDialog = new Dialog(this,R.style.CustomDialogTheme);
            twsbiImageDialog.setContentView(R.layout.twsbi_logo_dialog);
            twsbiImageDialog.setCancelable(true);

            // To visit Website ===================================
            Button visitWebsiteButton = (Button) twsbiImageDialog.findViewById(R.id.visitWebsiteButton);
            visitWebsiteButton.setOnClickListener(new View.OnClickListener() {
            @Override
                public void onClick(View v) {
                    twsbiImageDialog.dismiss();
                    Intent in = new Intent(FingerPaint.this,GoogleSite.class);
                    startActivity(in);
                }
            });

            // For About ===================================
            Button aboutButton = (Button) twsbiImageDialog.findViewById(R.id.aboutButton);
            aboutButton.setOnClickListener(new View.OnClickListener() {
            @Override
                public void onClick(View v) {
                    twsbiImageDialog.dismiss();
                    //System.out.println("I Am here before Dialog");
                    aboutDialog = new Dialog(getApplicationContext(),R.style.CustomDialogTheme);
                    aboutDialog.setContentView(R.layout.about_dialog);
                    aboutDialog.setCancelable(true);

                     Button okButton = (Button) aboutDialog.findViewById(R.id.okButton);
                     okButton.setOnClickListener(new View.OnClickListener() {
                     @Override
                         public void onClick(View v) {
                            aboutDialog.dismiss();
                         }
                     });
                     aboutDialog.show();
                    //openAboutDialog();

                }

            });
            twsbiImageDialog.show();

如果我这样做，我会收到如下错误：

12-05 11:43:21.568: ERROR/AndroidRuntime(545): FATAL EXCEPTION: main
12-05 11:43:21.568: ERROR/AndroidRuntime(545): android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at android.view.ViewRoot.setView(ViewRoot.java:509)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:177)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at android.app.Dialog.show(Dialog.java:241)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at com.project.twsbi.FingerPaint$8.onClick(FingerPaint.java:546)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at android.view.View.performClick(View.java:2408)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at android.view.View$PerformClick.run(View.java:8816)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at android.os.Handler.handleCallback(Handler.java:587)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at android.os.Handler.dispatchMessage(Handler.java:92)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at android.os.Looper.loop(Looper.java:123)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at android.app.ActivityThread.main(ActivityThread.java:4627)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at java.lang.reflect.Method.invokeNative(Native Method)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at java.lang.reflect.Method.invoke(Method.java:521)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
12-05 11:43:21.568: ERROR/AndroidRuntime(545):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

Context context;

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout......);

        context = this;
    }

对话框内的对话框：

    aboutDialog = new Dialog(context, R.style.CustomDialogTheme);             
            aboutDialog.setContentView(R.layout.about_dialog);        
            aboutDialog.setCancelable(true); 

Answer 2

使用当前活动作为上下文：

aboutDialog = new Dialog(ActivityName.this,R.style.CustomDialogTheme);

Answer 3

我认为不要在按钮第二个对话框打开代码中使用 getApplicationContext() 。使用此页面的上下文。

试试这个，也许会对你有帮助。